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PhD Thesis Heavy resistance exercise in breast cancer survivors at risk for lymphedema Kira Bloomquist The University Hospitals Centre for Health Research (UCSF), University of Copenhagen, Rigshospitalet Academic Supervisors Lis Adamsen, Sandra C Hayes, Peter Oturai, Tom Møller, Bent Ejlertsen

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Page 1: Heavy resistance exercise in breast cancer survivors at risk for …2018.+Heavy... · Danish summary (Dansk resume’) ... Further, thank you to Megan L. Steele for your friendship

PhD Thesis

Heavy resistance exercise

in breast cancer survivors at risk for lymphedema

Kira Bloomquist

The University Hospitals Centre for Health Research (UCSF), University of Copenhagen, Rigshospitalet

Academic Supervisors

Lis Adamsen, Sandra C Hayes, Peter Oturai, Tom Møller, Bent Ejlertsen

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Title Heavy resistance exercise in breast cancer survivors at risk for lymphedema

Author Kira Bloomquist, MHS, PT

Academic Supervisors Principal supervisor Lis Adamsen, Professor, RN, MSc.Soc., PhD University Hospitals Centre for Health Research (UCSF), Copenhagen University Hospital, Rigshospitalet, Copenhagen Ø, Denmark Department of Public Health, University of Copenhagen Primary co-supervisor, Sandra C Hayes, Professor, PhD Institute of Health and Biomedical Innovation, School of Public Health and Social Work, Queensland University of Technology, Brisbane, Australia Co-supervisor Peter Oturai, Chief Physician, MD, Department of Clinical Physiology, Nuclear Medicine and PET, Copenhagen University Hospital, Rigshospitalet, Copenhagen, Denmark Co-supervisor Tom Møller, Associate professor, RN, MPH, PhD University Hospitals Centre for Health Research (UCSF), Copenhagen University Hospital, Rigshospitalet, Copenhagen Ø, Denmark Co-Supervisor Bent Ejlertsen, Professor, MD, PhD Dept. of Oncology, The Finsen Centre and Danish Breast Cancer Group (DBCG), Copenhagen University Hospital, Rigshospitalet, Copenhagen Ø, Denmark

Financial Support The PhD has been supported by grants from the Center for Integrated Rehabilitation of Cancer Patients (CIRE), established by the Danish Cancer Society and The Novo Nordisk Foundation and the University Hospitals Centre for Health Research (UCSF), Copenhagen University Hospital, Rigshospitalet

Submitted January 2, 2018 PhD defense May 24, 2018 Assessment Committee Christoffer Johansen (chair), Professor, MD, Dept. of Oncology, The Finsen

Centre, Copenhagen University Hospital, Rigshospitalet and Danish Cancer Society

Jens Ahm Sørensen, Professor, MD, Head of research, Dept. of Plastic and Reconstructive Surgery, Odense Universitets Hospital, University of Southern Denmark

Anna Campbell, Associate professor in Clinical Exercise Science, Edinburgh Napier University

ISBN 978-87-90769-17-8

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Table of content Table of content ................................................................................................................................................. 1

Acknowledgements ........................................................................................................................................... 4

List of manuscripts ............................................................................................................................................ 4

Abbreviations .................................................................................................................................................... 6

Summary............................................................................................................................................................ 7

Danish summary (Dansk resume’) .................................................................................................................. 10

Introduction ..................................................................................................................................................... 13

Background...................................................................................................................................................... 14

Breast cancer ............................................................................................................................................... 14

Ramifications of breast cancer-related lymphedema ................................................................................... 15

The lymphatic system and breast cancer ..................................................................................................... 15

Epidemiology of BCRL ............................................................................................................................... 16

BCRL diagnosis and clinical progression ................................................................................................... 17

BCRL treatment........................................................................................................................................... 18

Risk reduction recommendations and exercise............................................................................................ 19

Resistance exercise ...................................................................................................................................... 20

Heavy-load resistance exercise during adjuvant chemotherapy .................................................................. 20

Body & Cancer ............................................................................................................................................ 21

Aim .................................................................................................................................................................. 23

Material and methods ...................................................................................................................................... 24

Design .......................................................................................................................................................... 24

Study 1 ..................................................................................................................................................... 24

Study 2 ..................................................................................................................................................... 24

Study 3 ..................................................................................................................................................... 24

Participants .................................................................................................................................................. 26

Study 1 ..................................................................................................................................................... 26

Study 2 ..................................................................................................................................................... 26

Study 3 ..................................................................................................................................................... 28

Setting .......................................................................................................................................................... 29

Randomization and blinding ........................................................................................................................ 29

Study 2 ..................................................................................................................................................... 29

Study 3 ..................................................................................................................................................... 29

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Interventions ................................................................................................................................................ 29

Study 2 ..................................................................................................................................................... 29

Study 3 ..................................................................................................................................................... 30

Measurement methods/outcomes ................................................................................................................ 31

Study 1 ..................................................................................................................................................... 31

Study 2 ..................................................................................................................................................... 32

Study 3 ..................................................................................................................................................... 33

Data analysis ................................................................................................................................................ 34

Study 1 ..................................................................................................................................................... 35

Study 2 ..................................................................................................................................................... 35

Study 3 ..................................................................................................................................................... 36

Ethical approval ........................................................................................................................................... 37

Study 1 ..................................................................................................................................................... 37

Study 2 ..................................................................................................................................................... 37

Study 3 ..................................................................................................................................................... 37

Results ............................................................................................................................................................. 37

Study 1 ......................................................................................................................................................... 37

Participants .............................................................................................................................................. 37

Body & Cancer participation ................................................................................................................... 38

BCRL point prevalence ........................................................................................................................... 38

BCRL vs. No BCRL ................................................................................................................................ 39

Study 2 ......................................................................................................................................................... 41

Participants .............................................................................................................................................. 41

Individual responses to resistance exercise ............................................................................................. 42

L-Dex ....................................................................................................................................................... 43

Inter-arm volume % difference ................................................................................................................ 43

BCRL symptoms ..................................................................................................................................... 43

Adverse events ......................................................................................................................................... 43

Study 3 ......................................................................................................................................................... 45

Participants .............................................................................................................................................. 45

Retention, adherence and adverse events ................................................................................................ 46

Lymphedema ........................................................................................................................................... 46

Upper extremity muscular strength ......................................................................................................... 49

Breast cancer-specific functional and symptom domains ....................................................................... 49

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Discussion........................................................................................................................................................ 50

Lymphedema ............................................................................................................................................... 50

Point prevalence ...................................................................................................................................... 52

Muscular strength ........................................................................................................................................ 52

Methodological considerations .................................................................................................................... 53

Internal validity ....................................................................................................................................... 53

External validity ...................................................................................................................................... 56

Conclusion and clinical implications ............................................................................................................... 57

Perspectives and future research ...................................................................................................................... 58

References ....................................................................................................................................................... 60

Appendices ...................................................................................................................................................... 66

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Acknowledgements I wish to express my sincere gratitude to everyone who contributed to the realization and completion of this thesis.

First and foremost, I would like to thank all of my supervisors. You all have brought experience and professional wisdom from

within your areas of expertise which have enriched my process and benefitted the thesis. To my principal supervisor Professor Lis

Adamsen, thank you for the opportunity to take on this work- without your support and belief in my abilities this thesis would not

have been realized. Enormous thanks goes to my primary co-supervisor Professor Sandi Hayes for the chance to come to Brisbane

and for excellent constructive supervision- I feel truly privileged to have worked with you. Further, special thanks goes to co-

supervisor Associate Professor Tom Møller for the opportunity to collect additional data in Study 3 and for support both

professionally and personally, and to Professor Bent Ejlertsen for coming on board with no hesitation- your clinical expertise and

knowledge of breast cancer treatment has been an asset alongside an incredibly pleasant demeanor. Finally, thanks to Chief Physician

Peter Oturai for many hours spent point-typing DXA scans, as well as providing constructive and timely feedback. Here I also want

to extend my gratitude to your staff for their willingness to collaborate and for excellent data collection.

I would also like to give tremendous thanks to Associate Professor, senior statistician Karl B. Christensen for statistical assistance in

all three studies. Thank you for your guidance in matters that I still only slightly understand. Further, thank you to Megan L. Steele

for your friendship and additional assistance in Study 2- equivalence, repeated measures over time, cross-over, GEE and interval

inclusion…. Need I say more?

I would also like to extend my gratitude to the breast cancer teams at the oncology departments of Rigshospitalet and Herlev hospital.

Thank you for your flexibility and willingness to adjust chemotherapy schedules so participants could partake in the studies. Further,

I would like to thank the breast cancer team at the Copenhagen Centre for Cancer and Health for help in recruitment of participants.

Clinical trials are only possible with the support of clinicians like you, who with an already busy work-load see the value in research

and make the time.

I also would like to express my deepest gratitude to the study participants who have dedicated their time and effort to this work.

Without your participation, these studies could not have carried out. Participating in research is an unselfish act as it does not

implicitly benefit you, the research subject, but rather future patients. Thank you for your contribution. You have made a difference.

I also would like to give my heartfelt thanks to all of my colleagues at UCSF (past and present), my “UCSF family”. Thank you for a

supportive and inspiring environment, for the laughter and for making UCSF a great place to come to work. Special thanks goes to

Christina Andersen for your unending support and for always taking the time for a chat, and Morten Quist for testing destiny and

your motto of “everything is possible”. Thanks to Julie Midtgaard for academic inspiration as well as girl-talk, and to fellow PhD-

student Eik Bjerre for your passion of methodology and high ethical standards. Also, thanks to the current Body and Cancer team:

Christian Lillelund for your contributions to the design and implementation of Studies 2 and 3 and for always making it fun to train,

and Birgit Nielsen for your stability and support in collecting data when I needed an extra hand, and to Jesper Børsen, my winter-

bathing friend, for filling in for me and ensuring that data was collected when I was gone. Thanks to Birgitte Nielsen for diligent data

collection and keying and assistance in Body and Cancer, and to Mikael Rørth for your support and advice based on your many years

of clinical research experience. Thanks to former office mates, Jakob Uth for your underplayed demeanor and fantastic sense of

humor and Karin Piil for setting the bar for how a Phd should be carried out. Thanks also to Mary Jarden, my fellow American for

“Denglish talk” and encouragement and to Jesper Frank Christensen for patiently trying to explain statistical matters as well as

assistance in the randomization of participants in Study 2. Further, thanks to research assistants Nicolas Kjerulf, Liza Wiedenbein,

Maria Petersen, Asker Kristensen, Marie Hagmann and Jonas Ravn for help in data collection and keying, as well as Maja Bohlbro

for also contributing to the preparation of data for analysis in Study 3. Thanks also to Kjeld Jensen for enduring support in practical

matters and last but not least, thanks to Bente Kronborg and Anders Larsen for always having an open door and providing friendly

and competent assistance. You have an enormous positive impact on the department and I thank you for that.

Finally I would like to thank all of my friends and family for support and for still being there despite my lack of engagement the last

couple of years. Special thanks goes to fellow PhD students Marie Collett and Britt Morthorst- it has been a gift to share the Phd ride

with you. Also thanks to my “Måge family”- I feel incredibly lucky to share daily life with you all, as well as my “Dragon boat

family” for your support and dedication to spreading the message of an active life during and after breast cancer. Also, an enormous

thanks goes to my parents Bente Nielsen and Gordon Bloomquist. Thank you for your love and support and for inspiring a sense of

social responsibility to try to make a difference. My deep felt gratitude also goes to Tim Barrett for assuring me that I was ok when I

doubted my own capabilities, and for supporting me in my journey from “Lille Mor” to “Dr. Mor”. Finally, to my daughter Aviaja,

thank you for an unwavering belief that I would successfully complete this thesis. May you possess the same unwavering belief in

yourself.

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List of Manuscripts

This thesis is based on the following manuscripts:

Paper I

Bloomquist K, Karlsmark T, Christensen KB, Adamsen L. Heavy resistance training and

lymphedema: Prevalence of breast cancer-related lymphedema in participants of an exercise

intervention utilizing heavy load resistance training. Acta Oncol. 2014;53(2):215-25

Paper II

Bloomquist K, Hayes S, Adamsen L, Møller T, Christensen KB, Ejlertsen B, Oturai P. A

randomized cross-over trial to detect differences in arm volume after low- and heavy-load

resistance exercise among patients receiving adjuvant chemotherapy for breast cancer at risk for

arm lymphedema: study protocol. BMC Cancer. 2016;16:517

Paper III

Bloomquist K, Oturai P, Steele M, Adamsen L, Møller T, Christensen KB, Ejlertsen B, Hayes S.

Heavy-load lifting: Acute response in breast cancer survivors at risk for lymphedema. Med Sci

Sports Exerc. 2018; 50(2):187-95

Paper IV

Bloomquist K, Adamsen L, Hayes S, Lillelund C, Andersen C, Christensen KB, Oturai P, Ejlertsen

B, Tuxen MK, Møller T. Heavy-load resistance exercise in pre-diagnosis physically inactive

women at risk of breast cancer-related lymphedema during adjuvant chemotherapy: a randomized

trial. Manuscript prepared for submission to Acta Oncologica.

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Abbreviations

ALND Axillary lymph node dissection

SLNB Sentinel lymph node biopsy

BCRL Breast cancer-related arm lymphedema

RH Rigshospitalet

HE Herlev Hospital

BIS Bioimpedance spectroscopy

DXA Dual-energy X-ray absorptiometry

EORTC QLQ-BR23 European Organization for Research and Treatment of Cancer quality of life

questionnaire breast-23

NRS Numeric rating scale

RM Repetition maximum

WHO World Health Organization

ICC Intraclass correlation coefficient

SE Standard error of the mean

SD Standard deviation

IQR Interquartile range

ITT Intention- to- treat

GEE Generalized estimating equation

CDT Complete decongestive therapy

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Summary

Background

Despite a paucity of evidence, breast cancer survivors have historically been advised to refrain from

a number of activities including lifting heavy objects and resistance exercise in an effort to reduce

the risk of breast cancer-related lymphedema. However, clinical trials carried out over the last two

decades have consistently demonstrated that resistance exercise can be conducted without increased

risk of lymphedema. Nonetheless, as previous work utilized exercise prescription with low- to

moderate loads, uncertainty exists as to the upper-limits of resistance exercise loading, and breast

cancer survivors at risk for lymphedema continue to be encouraged to avoid heavy-lifting. Yet

exercise science literature indicates that a dose-response relationship exists between loads lifted and

gains in muscular strength and function, of potential benefit for breast cancer survivors receiving

chemotherapy. Therefore, the purpose of this thesis was to explore the safety of heavy-load

resistance exercise among women at risk of developing breast cancer-related lymphedema while

undergoing adjuvant chemotherapy.

Material and methods

Three studies were undertaken. Study 1 This was a cross-sectional trial including women treated

with chemotherapy for breast cancer (n = 149) who had participated in the Body & Cancer program

between January 2010 and December 2011. The Body & Cancer program is a six-week multimodal

exercise program including heavy-load resistance exercise. The primary outcome, self-reported

diagnosis of breast cancer-related lymphedema, was obtained from a structured telephone interview

carried out on average 14 months after participation in the exercise program. Study 2 This was a

randomized cross-over trial including women receiving adjuvant taxane-based chemotherapy for

breast cancer who had undergone axillary lymph node dissection (n =21). Participants were

randomly assigned to participate in a low- (two sets of 15–20 repetition maximum) and heavy-load

(three sets of 5–8 repetition maximum) upper extremity resistance exercise session first, with a one

week wash-out period between sessions. Swelling was determined by bioimpedance spectroscopy

(BIS) and dual energy x-ray absorptiometry (DXA), and breast cancer-related lymphedema

symptoms (heaviness, swelling, pain, tightness) were reported using a numeric rating scale (NRS)

(0-10). Outcomes were assessed immediately pre- and post-exercise, and 24- and 72-hours post-

exercise. Generalized estimating equations were used to evaluate changes over time between

groups, with equivalence between resistance exercise loads determined using the principle of

confidence interval inclusion. Study 3 This was a parallel group, randomized trial. Screened pre-

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diagnosis physically inactive women receiving adjuvant chemotherapy for breast cancer (n=153)

participated in 12 weeks of 1) HIGH: supervised multimodal exercise including heavy-load

resistance exercise (85-90% 1 repetition maximum (RM), three sets of 5-8 repetitions) or 2) LOW:

walking supported by pedometer and one-on-one consultations. Outcomes were assessed at

baseline, 12 and 39 weeks and included: swelling (BIS, L-Dex scores; DXA, inter-arm volume %

difference; self-report, n( %)), lymphedema symptoms (NRS, 0-10), upper extremity strength (1

RM), and self-reported breast cancer specific function and symptoms (EORTC QLQ-BR23). Linear

mixed models with a heterogeneous autoregressive (1) covariance structure were used to evaluate

changes over time between groups. Equivalence was hypothesized for lymphedema outcomes, and

was determined using the principle of confidence interval inclusion.

Results

Study 1 On average, 14 months (range 4-26 months) post-participation in Body & Cancer, 27.5%

reported having been diagnosed with lymphedema by a clinician. When restricted to women with

axillary node dissection, 44.4% reported a clinician diagnosis of BCRL. No statistically significant

association between change in muscle strength during Body & Cancer and the development of

lymphedema was observed, nor was self-reported participation in resistance exercise with heavy

loads up to three months post-intervention. Study 2 The acute response to resistance exercise with

low and heavy loads was equivalent, with the exception of extracellular fluid at 72-hours post-

exercise with less swelling following heavy-loads. Study 3 Post-intervention equivalence between

groups was found for L-Dex and self-reported heaviness, tightness and swelling. Non-equivalence

was determined for inter-arm volume and pain, as deviations beyond equivalence margins indicated

reductions associated with participation in the HIGH intervention for these two outcomes. Further,

greater increases (p < 0.05) in upper extremity strength were seen in the HIGH group compared to

LOW at all assessments, and clinically relevant within group reductions in breast and arm

symptoms were observed in the HIGH group at 6 and 12 weeks.

Conclusion

The findings presented in this thesis indicate that breast cancer survivors at risk of breast cancer-

related lymphedema, can participate in and benefit from heavy-load resistance exercise while

receiving taxane-based chemotherapy, without an increased risk of exacerbating the development of

lymphedema.

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Perspectives

Previous clinical trials using low to moderate resistance exercise loads have found gains in muscle

strength while mitigating adverse changes in physical components of quality of life, including

fatigue in this population, and it has been hypothesized that resistance exercise reduces taxane-

related edema. However, due to the dose-response relationship that exists between loads lifted and

gains in muscular strength and function it is feasible that superior benefits can be gained with

resistance exercise with heavier loads. Further it is plausible that participation in heavy-load

resistance exercise may instigate more effective lymphatic function than low-load resistance

exercise, and in doing so, potentially have a greater effect on reducing lymphedema risk. Therefore,

as this thesis indicates that resistance exercise safely can be performed with heavy loads, future

studies should carry out a head to head comparison between resistance exercise protocols to

establish optimal resistance exercise prescription for breast cancer survivors.

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Danish summary (Dansk resume’)

Baggrund

Trods manglende evidens er brystkræftoverlevere blevet frarådet en række fysisk krævende

aktiviteter, bl.a. løft af tunge genstande og styrketræning, i et forsøg på at reducere risikoen for

brystkræftrelateret lymfødem. Igennem de sidste to årtier har kliniske forsøg imidlertid vist, at

styrketræning kan udføres uden øget risiko for lymfødem blandt kvinder diagnosticeret med

brystkæft. Der er dog fortsat uklarhed om de øvre grænser for vægtbelastningen ved styrketræning,

da tidligere forsøg har anvendt lav til moderat vægt i de gennemførte interventioner. Den

idrætsfysiologiske litteratur indikerer imidlertid, at der eksisterer et dosis-responsforhold mellem

vægtbelastninger og fremgang i forhold til muskelstyrke og –funktion, af potentiel positiv

betydning for brystkræftoverlevere, der modtager kemoterapi. Formålet med denne afhandling var

derfor at undersøge, hvor vidt det er sikkert at styrketræne med tung belastning for kvinder, der er i

risiko for at udvikle brystkræftrelateret lymfødem, under adjuverende kemoterapi.

Metode

Der blev gennemført tre studier. Studie 1 var et tværsnitsstudie, som inkluderede kvinder behandlet

for brystkræft med kemoterapi (n = 149), og som parallelt hertil deltog i Krop & Kræft i perioden

januar 2010 til december 2011. Krop & Kræft er et seks-ugers multimodalt træningsprogram, som

blandt andet indeholder tung styrketræning. Det primære effektmål var selvrapporteret

brystkræftrelateret lymfødem. Data blev indsamlet med et struktureret telefoninterview gennemført

i gennemsnit 14 måneder efter afsluttet deltagelse i Krop & Kræft. Studie 2 var et randomiseret

cross-over studie, som inkluderede kvinder med aksil-dissektion, der modtog adjuverende

taxanbaseret kemoterapi for brystkræft (n=21). Deltagerne blev tilfældigt allokeret til at deltage i en

styrketræningssession med lav (to sæt af 15-20 gentagelser) henholdsvis tung (tre sæt af 5-8

gentagelser) vægtbelastning, med en uges ”wash-out” periode mellem de to

styrketræningssessioner. Ekstracellulær væske i armene blev målt med bioimpedansspektroskopi

(BIS) og dual X-ray absorptiometri (DXA), og symptomer relateret til brystkræftrelateret lymfødem

(fornemmelse af stramhed, tyngde, hævelse, smerte) blev registreret med en numerisk rating skala

(NRS) (0-10). Målingerne blev foretaget umiddelbart før og efter styrketræningssessionerne samt

24 og 72 timer efter. Til at evaluere ændringer over tid mellem grupperne blev generalized

estimating equations anvendt. Ækvivalens mellem styrketræningssessionerne (lav / tung) blev

bestemt ved anvendelse af confidence interval inclusion. Studie 3 var et parallel-gruppe,

randomiseret forsøg. Kvinder, der inden deres brystkræft diagnose var defineret som fysisk inaktiv

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(screenet) og som modtog adjuverende kemoterapi (n = 153) deltog 12 uger i: 1) HIGH:

Superviseret multimodalt træningsprogram med tung styrketræning (85-90% 1 repetitions

maksimum (RM), tre sæt 5-8 gentagelser) eller 2) LOW: Gangtræningsintervention med skridttæller

og face-to-face rådgivning. Data blev indsamlet ved baseline, samt efter 12 og 39 uger og

inkluderede: hævelse af armene (BIS, L-Dex-score; DXA, inter-arm volumen % forskel;

selvrapporteret hævelse, n (%)), lymfødem-symptomer (NRS, 0-10), muskelstyrke (1 RM) samt

selvrapporteret brystkræftspecifik funktion og symptomer (EORTC QLQ-BR23). Linear mixed

models med en heterogen autoregressiv (1) kovarians struktur blev anvendt til at evaluere ændringer

over tid mellem grupperne. Ækvivalens blev bestemt ved anvendelse af confidence interval

inclusion for effektmål relateret til lymfødem

.

Resultater

Studie 1 I gennemsnit 14 måneder efter deltagelse i Krop & Kræft (interval 4-26 måneder)

rapporterede 27,5% at de var blevet diagnosticeret med lymfødem (lymfødemterapeut eller læge).

Ved sub-analyse af kvinder med aksil-dissektion rapporterede 44,4% at være blevet diagnosticeret

med lymfødem. Der blev ikke observeret en statistisk signifikant association mellem ændring i

muskelstyrke og udvikling af lymfødem, hverken efter deltagelse i Krop & Kræft eller efter

selvrapporteret deltagelse i styrketræning med tung belastning op til tre måneder efter deltagelse.

Studie 2 Det akutte respons til styrketræning med lav og tung vægtbelastning var ækvivalent, med

undtagelse af ekstracellulær væske ved 72 timers opfølgning, som indikerede mindre væske efter

tung vægtbelastning. Studie 3 Post-intervention ækvivalens mellem grupper blev fundet for L-Dex

og selvrapporterede symptomer (tyngde, stramhed og hævelse). For inter-arm volumen og smerte

kunne ækvivalens ikke demonstreres, men indikerede større reduktioner associeret til deltagelse i

HIGH interventionen sammenlignet med LOW for disse to effektmål. Analyser af muskelstyrke

viste, at HIGH gruppen øgede muskelstyrken i overekstremiteterne (p <0,05) sammenlignet med

LOW. Desuden blev bryst- og arm-symptomer reduceret ved 6 og 12 uger i HIGH gruppen, uden

signifikant forskel mellem grupperne.

Konklusion

Resultaterne fra denne afhandling indikerer, at kvinder med brystkræft i risiko for at udvikle

brystkræftrelateret lymfødem kan deltage i og profitere af tung styrketræning under behandling med

taxanbaseret kemoterapi uden øget risiko for udvikling af lymfødem.

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Perspektivering

Set i lyset af det dosis-responsforhold der eksisterer mellem belastning og fremgang i muskelstyrke

og -funktion, kan der antageligvis opnås større fordele ved styrketræning med tungere vægte. Det er

ligeledes plausibelt at deltagelse i styrketræning med tung belastning potentielt kan medføre en

mere effektiv lymfatisk funktion end styrketræning med lav belastning og dermed have en positiv

effekt på risikoen for at udvikle lymfødem. Da denne afhandling indikerer, at styrketræning med

tung belastning er sikker at udføre, bør fremtidige undersøgelser derfor sammenligne

styrketræningsprotokoller for at klarlægge den optimale styrketræningsdosering for

brystkræftoverlevere i risiko for at udvikle lymfødem.

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Introduction

Breast cancer-related lymphedema (BCRL) is a feared adverse effect of breast cancer treatment (2,

3) affecting approximately one in five breast cancer survivors (4). At present, though evidence

suggests a predisposition for developing BCRL (5, 6) ability to accurately predict who will develop

BCRL is limited.

Historically, breast cancer survivors have been advised to refrain from a number of activities

including lifting heavy objects and resistance exercise in an effort to avoid the development of

BCRL (7-9). These recommendations were based on anecdotal concerns, that heavy-lifting would

increase lymph production, which would then overload an impaired lymph system and thus trigger

the development of BCRL (9).

During the last two decades, numerous studies have evaluated and consistently demonstrated that

resistance exercise is beneficial to strength and outcomes of importance for quality of life, and can

be conducted without increased risk of BCRL after treatment for breast cancer (7, 8, 10, 11).

However, as previous work utilized exercise prescription with low- to moderate loads, breast cancer

survivors continue to be encouraged to avoid heavy-lifting. Further, there is a paucity of evidence

confirming upper-limits of resistance exercise loading for women at risk of BCRL.

At present, two prospective studies have evaluated the safety of resistance exercise with heavy

loads in women with clinically stable BCRL who had been diagnosed with breast cancer at least a

year before study inclusion (12, 13). Both studies found that the extent of arm swelling and

associated BCRL symptoms remained stable immediately post-, 24- and 72-hours after one bout of

resistance exercise (12), and after twelve-weeks of regular resistance exercise, irrespective of

whether low- or heavy-loads were lifted (13). While these findings provide meaningful information

for breast cancer survivors with BCRL who have completed chemotherapy and radiotherapy, they

cannot be generalized to the at-risk population undergoing chemotherapy.

This thesis focuses therefore on the safety of resistance exercise with heavy loads during adjuvant

chemotherapy in breast cancer survivors at risk for lymphedema.

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Background

Breast cancer

Breast cancer is the second most common cancer in the world after lung cancer, and is the most

frequent cancer among women with an estimated 1.67 million new cases diagnosed in 2012,

representing 25% of all cancers in women (14). In 2015, 4,767 women were diagnosed with breast

cancer in Denmark, corresponding to 24.8% of all cancers. Comparatively, just 38 men were

diagnosed with breast cancer in the same period (15). Survival rates vary worldwide, but in general

rates have improved especially in countries where breast cancer is detected early and there is access

to improved treatment strategies (14). Treatment modalities for breast cancer include surgery,

chemotherapy, radiotherapy as well as targeted and hormonal therapy, with subtype and stage of

breast cancer determining treatment strategy (16). While these treatment modalities are increasingly

effective in terms of survival, they are also associated with a range of treatment specific adverse

acute and late side effects including fatigue, pain and lymphedema that negatively impact the

quality of life of breast cancer survivors (17-19). In Denmark, breast cancer prevalence has

increased over the past decades (Figure 1) and five year survival rates from 2014 were estimated at

86% (1). As such, with more people surviving breast cancer, adverse late effects, are a growing

public health concern.

Figure 1. Age-standardized breast cancer prevalence in men and women in Denmark (1990-2014)

Adapted from the NORDCAN database, ancr.nu (1).

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Ramifications of breast cancer-related lymphedema

BCRL is initially characterized by accumulation of excess protein-rich extracellular fluid resulting

in regional swelling of the hand, arm, breast or torso on the surgical side as a consequence of

disruption or damage to the axillary lymphatic system due to breast cancer treatment (9, 20-23).

This incurable condition is negatively associated with significant physical, functional, social and

psychological burden (24-27) impacting daily living, work and quality of life (24, 28-30). BCRL

and efforts to reduce the risk of BCRL impose limitations on the lives of breast cancer survivors,

with some women reporting more distress related to the threat of BCRL than with breast cancer

itself (3). BCRL is a persistent reminder of breast cancer and the physical and functional

manifestations include decreased mobility, skin changes and visible swelling as well as sensory

disturbances, discomfort and pain (3, 22). Considerable psychosocial effects are also associated

with BCRL including negative perceptions of self-image, appearance and sexuality (25, 26).

Further, breast cancer survivors with lymphedema are faced with extra financial burden due to the

cost of lymphedema treatment (31) as well as the economic ramifications of reducing work hours,

changing work places or exiting the workforce which can be a necessity especially for those with

more severe lymphedema (25, 28, 32).

The lymphatic system and breast cancer

The lymphatics are a one-way transport system that carries fluid and plasma proteins that have

leaked from tissues into the interstitial space, back into the cardiovascular system (33). The

lymphatic system supports the cardiovascular and immune systems and has three major functions

including maintenance of fluid balance (homeostasis), fat absorption by the intestinal lymphatics,

and immunological defense (21). The lymphatic system aids in the removal of excess fat, water,

cellular debris and foreign material from body tissues, as well as larger proteins by way of lymph

fluid transport. Lymph fluid is derived from interstitial fluid upon entry into lymph capillaries that

are found near the arteriovenous anastomoses that serve all systemic tissues (9, 21). Formation and

propulsion of lymph through lymphatic vessels is primarily dependent on extrinsic mechanisms

such as skeletal muscle contraction (muscle pump) and pressure changes due to respiration and

arterial pressure pulsations (33). However, once lymph fluid moves beyond the lymphatic

capillaries, movement of lymph is dependent on contraction of smooth muscle that line the

contractile lymphatic vessels driven by pacemaker cells as well as one-way valves that help prevent

backflow (lymphatic pump) (21, 33). The lymphatic system is comprised of a superficial layer

(drainage for skin and subcutaneous tissues) and a deep layer (drainage for e.g. muscles, joints and

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bones) that drain into site specific lymph nodes that filter foreign particles, process antigens and

produce appropriate immune response (5). As such, bacteria, proteins and other materials from a

specific body part are delivered to a specific lymph node that serves that tissue. Consequently, if

lymph nodes are damaged or removed, the immune response is interrupted as well as the ability to

remove excess fluid from the tissue supported by the specific lymph node and explains, in part,

potential ensuing edema of that region (9, 21).

The lymphatic vessels that transport lymph from the breast to the axillary lymph

nodes are the preferential route for the metastatic spread of breast cancer, with status of the axillary

lymph nodes a determinant of breast cancer staging and subsequent treatment (6, 21, 34). The

sentinel node (or nodes) is typically the first lymph node to which cancer cells spread from

a primary tumor, and histopathological examination by means of a sentinel lymph node biopsy

(SLNB) determines whether cancer cells are present. A negative SLNB suggests that cancer has not

spread to nearby lymph nodes and no further surgery is warranted. However, in Denmark if the

biopsy contains macrometastasis or micrometastasis/isolated tumorcells in 3 or more sentinel nodes,

subsequent removal of the axillary lymph nodes, usually levels 1 and 2, known as axillary lymph

node dissection (ALND) is performed (35). Consequently, as more lymph nodes are removed,

compared to SLNB, ALND is associated with considerably more morbidity and an increased risk of

developing BCRL(4). However, not all breast cancer survivors with ALND develop lymphedema,

and cases of grade 1or higher lymphedema are seen in breast cancer survivors with only SLNB,

irrespective of axillary radiotherapy. At present, though a predisposition for BCRL likely exists, the

complex pathophysiology of BCRL remains unclear rendering limited ability to predict who will

develop this condition (6, 21).

Epidemiology of BCRL

The incidence of BCRL is difficult to quantify

with factors such as type of study design, time

since- and type of breast cancer treatment and

method of lymphedema assessment affecting

incidence rates (4). In Denmark, an incidence of

860 to 1260 new cases per year has been

estimated (31) and a nationwide study by

Gartner et al. (36) found point prevalence of self-

reported BCRL symptoms corresponding to 37%

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in 2008 and 31% in 2012, in women who had received treatment for unilateral breast cancer in 2005

and 2006. To date, the best estimate of BCRL incidence is based on a systematic review and meta-

analysis by Disipio et al., 2013, which found a cumulative incidence rate of 16.6% (95% CI 13.6 –

20.2), based on data from 72 studies (4). However, when restricted to 30 prospective cohort studies,

the incidence estimate was 21.4% (14.9- 29.8). In breast cancer survivors with ALND, incident

BCRL (18 studies) was approximately four times higher (19.9%, 13.5 – 28.2) as compared to SLNB

(5.6%, 6-1 – 7.9%). Though risk of BCRL is lifelong, incident BCRL increased up to two years

post- surgery (18.9%, 14.2 - 24.7) based on 24 studies, after which time, incidence decreased (15.6

%, 10.0 – 23.5). This is in line with findings from a prospective study by Norman et al. (37) that

showed 80% of the women that developed BCRL, did so within 2 years post-surgery.

Findings from the aforementioned systematic review by Disipio and colleagues also

collated risk factor findings from 29 studies and found that there was ‘strong’ evidence

demonstrating the following characteristics increased risk of lymphedema: ALND / greater number

of lymph nodes removed, more extensive breast surgery and higher body mass index (BMI) ≥ 25.

Further, there was ‘moderate’ evidence suggesting that higher number of metastatic nodes, anti-

cancer treatment with chemotherapy and radiotherapy as well as physical inactivity also increased

risk of BCRL (4).

BCRL diagnosis and clinical progression

Though classification criteria for defining and grading BCRL severity have been developed

including a staging system by the International Society of Lymphology and Common Toxicity

Criteria from the National Cancer Institute (Table 1) (20, 22, 38), no universal definition of BCRL

exists. Further, no gold standard assessment of BCRL exists as current measurement methods

including circumferential measurements, self-report of symptoms, water displacement, perometry

and bioimpedance spectroscopy have advantages and disadvantages, as well as varying diagnostic

thresholds applied (4, 39). The inability to identify a gold standard definition and measure of

lymphedema is in part due to several challenges inherent to BCRL presentation. First, many breast

cancer survivors experience transient swelling related to surgery and taxane-based chemotherapy in

the first year after surgery that resolves by itself (40). However, as there is no accepted time line for

defining transient versus chronic lymphedema, some transient cases are mistakenly diagnosed as

chronic. Importantly, though, transient swelling during the first year after surgery has been

identified as a strong predictor of chronic BCRL at 18 months, why prospective monitoring of these

patients is warranted (41). Further, the distribution of swelling can vary from person to person.

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Swelling may for example be confined to a specific region such as the hand in some, while in others

swelling is restricted to the forearm or upper arm (5). Additionally, early BCRL is characterized by

a latent phase whereby an accumulation of excess extracellular fluid is present, but where no visible

swelling is detected. As BCRL progresses this then manifests as visible swelling (22), and then in

later stages the excess extracellular fluid initially characterizing BCRL is replaced with fibrotic and

adipose tissue (21). Therefore, it has been proposed that the use of multiple measures, incorporating

both objective and subjective measures may be the most comprehensive way to capture BCRL cases

and to monitor BCRL over time (4, 39).

ISL staging CTC v3.0 grading

0 Latent or subclinical LE

No evidence of swelling

Exists prior to overt edema

Normal

1 Pitting

Elevation of limb reduces swelling

<20% increase in limb volume

5%-10% inter-limb discrepancy in volume or circumference at point of greatest

visible difference; swelling or obscuration of anatomical architecture on close

inspection: pitting edema

2 Elevation of limb does not reduce

swelling

Pitting is present in early Stage II due

to tissue fibrosis

20% to 40% increase in limb volume

>10%-30% inter-limb discrepancy in volume or circumference at point of greatest

visible difference; readily apparent obscuration of anatomical architecture;

obliteration of skin folds; readily apparent deviation from normal anatomical

contour

3 Lymphostatic elephantiasis

Pitting is absent

Trophic skin changes present

>40% increase in limb volume

>30% inter-limb discrepancy in volume; lymphorrhea; gross deviation from normal

anatomical architecture; interfering with activities of daily living

4 Progression to malignancy (e.g., lymphangiosarcoma); amputation indicated;

disabling

BCRL treatment

The majority of BCRL is mild (20, 37) and the aim of treatment is to contain swelling and alleviate

symptoms. The current standard of treatment for BCRL “complete decongestive therapy” (CDT) is

comprised of multiple elements including a massage technique called manual lymph drainage,

compression (bandaging or garments) of the affected area, remedial exercises, skin care and

education in self-care (31, 38, 42). CDT is delivered by specially trained lymphedema therapists

and involves two phases. The aim of the first phase is to reduce the extent of swelling. This

intensive and time consuming phase can last up to four weeks and involves frequent therapist-

Table 1. Lymphedema staging and grading criteria: International Society of Lymphology (ISL) and

National Cancer Institute Common Toxicity Criteria version 3 (CTC v3.0)

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delivered treatment sessions including bandaging of the affected body part. After reaching a plateau

in the extent of swelling, home-based maintenance (phase two) then begins to retain the effects of

the intensive phase. Depending on the severity of the lymphedema this entails wearing a custom-

fitted compression garment during the day, performing remedial exercises, wearing special night

garments and using pneumatic compression devices (22). Though CDT involves two phases and

contains these various components, the treatment delivered is based on the clinical presentation

and could, for example, include only compression or manual lymph drainage. Other less common

treatment strategies include pharmacological and surgical approaches such as liposuction, lymph

node transplants, lymph-venous anastomosis (22, 23, 42), while the potential of stem cell surgery is

being explored (43). The treatment of lymphedema will not be addressed further in the present

thesis.

Risk reduction recommendations and exercise

Because uncertainty exists as to why some develop BCRL and others do not, and because

prevention of BCRL is preferable to the mitigation of BCRL symptoms, breast cancer survivors are

encouraged to adopt a range of precautionary behaviors in an effort to reduce the risk of BCRL (22,

44). The risk reduction guidelines or strategies are intended to minimize lymphatic overload of the

at-risk extremity, and are based in large part on pathophysiological principals and expert opinion

rather than scientific evidence (42, 45). These recommendations include avoiding constriction of the

at-risk arm (including blood pressure cuffs), extreme temperatures (e.g. sauna) and trauma or injury

and blood draws on the at-risk extremity (44, 45). Historically avoidance of vigorous, repetitive

upper-body activities was also recommended as well as avoidance of heavy lifting, often with

restrictions of not lifting more than 2-7 kilograms (9). As a consequence, daily living activities were

restricted (vacuuming, child care, grocery shopping) along with upper-body, recreational activities

including resistance exercise (9). However, a growing body of evidence has emerged over the last

two decades, with studies consistently finding participating in resistance exercise to be a safe and

effective exercise modality in breast cancer survivors at risk for lymphedema (7, 8, 10, 11).

Nonetheless, as exercise prescription of previous work has been limited to loads considered to be

low to moderately heavy, questions remain as to the safety of resistance exercise with heavy loads

and lymphedema risk (7). Additionally, uncertainty still exists as to whether intermittent heavy-

lifting in activities of daily living need be avoided (2, 46).

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Resistance exercise

Skeletal muscle has the ability to alter its phenotypic profile in response to specific stimuli with

aerobic and resistance exercise representing two exercise modalities with distinct ability to modify

skeletal muscle (47). Specifically, resistance exercise is characterized by short periods of high

contractile muscle performance against external load and is considered the optimal exercise

modality to increase muscle mass and strength (48-50).

The extent of strength enhancement is dependent on a number of exercise prescription

variables including the magnitude of loads lifted. The term repetition maximum (RM) is used to

describe resistance exercise prescription, with RM corresponding to the maximal amount of weight

lifted for a number of exercise movements. Thus, a 1 RM is the heaviest weight that can be lifted

once and only once, corresponding to maximal strength or 100% RM (51). As such, an 8 RM is the

heaviest weight that can be lifted only eight times. To induce desirable adaptations in muscle mass

and strength the American College of Sports Medicine recommends that resistance exercise should

be carried out at a minimum intensity corresponding to 60% 1 RM. Importantly, a dose-response

relationship exists in regard to loads lifted and gains in muscle strength outcomes, with loads of 80-

100% 1 RM or higher being recommended for continued, long-term progression in muscle strength

(48, 50). Additionally, beyond skeletal muscle adaptations, resistance exercise with heavy loads has

also been identified as an osteogenic exercise modality due to the adaptive nature of bone that

requires heavier loads (52).

Heavy-load resistance exercise during adjuvant chemotherapy

There are several reasons why resistance exercise with heavy loads is relevant during adjuvant

chemotherapy for breast cancer. First, participation in resistance exercise with low to moderate

loads (60-80% of 1 repetition maximum (RM) for 8-15 RM) has been found to reduce or mitigate

chemotherapy-related fatigue (53, 54) with evidence to suggest that a dose-response relationship

exists between increasing loads lifted and reductions of fatigue (53). Further, reductions in physical

activity contributing to weight gain, characterized as sarcopenic obesity, is common during adjuvant

chemotherapy for breast cancer (55-57). Sarcopenic obesity is defined as no change or decline in

muscle mass in the presence of increased body fat) (55), and is adversely associated with reductions

in muscle strength and functional impairment (49, 58). As such, resistance exercise represents an

important countermeasure (8, 54, 59) and is recognized as an effective modality to control or revert

sarcopenia, thereby contributing to improved functional levels and overall health (48, 49).

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Nonetheless, though increases in muscle strength and reductions in fatigue have been

observed with resistance exercise-prescription using lower loads, it is feasible that resistance

exercise with heavy loads, could yield superior reductions in fatigue and increases in muscle

strength. In turn, this could positively influence functional aspects of quality of life in this

population. Also, in Denmark, standard adjuvant chemotherapy for breast cancer consists of

combination taxane-based chemotherapy (16) with generalized swelling characterized by an

increased level of the interstitial component of extracellular fluid as a known side-effect (40, 60).

For some breast cancer survivors this may manifest as transient arm swelling and for others as

chronic lymphedema. It has been hypothesized that resistance exercise, through the effects of the

muscle pump, could mitigate the extent of arm swelling (33, 40). At present, no studies evaluating

the effect of resistance exercise and BCRL have explicitly included participants undergoing taxane-

based chemotherapy why uncertainty remains as to the impact of resistance exercise and resistance

exercise load on taxane-based swelling. This is especially relevant as the majority of individuals

who receive chemotherapy for breast cancer, receive taxane-based chemotherapy. Therefore, in

light of the potential for superior benefits, the safety of resistance exercise with heavy loads in

regard to BCRL development during taxane-based chemotherapy should be established.

Body & Cancer

Against this back-drop, the author of this thesis has been affiliated with the Body & Cancer

program since 2003. This program started in 2001 as a randomized controlled trial designed to

compare the effectiveness of a multimodal exercise intervention to a wait-list control group on rate

of cancer-related fatigue (61). Since 2007 Body & Cancer has been offered as an adjunct to

chemotherapy in the Copenhagen area, and is today offered at seven hospitals throughout Denmark.

To date, approximately 1800 participants representing over 21 diagnoses have participated in Body

& Cancer in the Copenhagen area alone, with approximately half receiving chemotherapy for breast

cancer.

The Body & Cancer program is a six-week, nine-hour weekly, group based (10-15

participants), multimodal exercise intervention comprised of both low-intensity components

(relaxation techniques, body awareness training and Swedish massage) and high-intensity

components (aerobic-and resistance exercise). Prior to each high intensity exercise session,

participants are screened (e.g. musculoskeletal issues, temperature, blood pressure) to ensure safety

of participation.

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In Copenhagen, exercise sessions are held at training facilities affiliated with the Copenhagen

University Hospital, Rigshospitalet and supervised by a cancer nurse specialist and physical

therapist. Of particular interest for this thesis is the high intensity component which consisted of an

aerobic-based warm-up followed by heavy-load resistance exercise followed by 15-30 minutes of

interval aerobic exercise on a stationary bike with peak loads of 85-95% of each participant’s

maximal heart rate. The resistance exercise program comprises of six machine-based exercises

(Technogym®, Gamettola, Italy), each targeting major muscle groups of the body including the

upper-extremities (chest press, latissimus pull down, abdominal crunch, back extension, leg press

and knee extension). Resistance exercise loads are based on a 1 RM strength test for each exercise.

During the first week participants are instructed to lift loads corresponding to 2-3 sets of 8-12

repetitions at 70% 1 RM, progressing to 80% 1 RM in week two. From week three forward, loads

lifted correspond to 3 sets of 5-8 repetitions at 80-90% 1 RM. Participants who develop signs of

BCRL (e.g. sensations of heaviness, visual swelling) or experience exacerbations of an existing

BCRL are instructed to reduce loads or refrain from exercises of the upper extremities and are

referred to a lymphedema therapist for evaluation and treatment. No data has previously been

collected regarding BCRL in this cohort.

Monday Tuesday Wednesday Thursday Friday

Aerobic and resistance

exercise (1.5 h) Body awareness (1.5 h)

Relaxation (.5 h)

Aerobic and resistance

exercise (2 h)

Aerobic and resistance

exercise (1.5 h)

Relaxation training (.5 h) Relaxation training (.5 h)

Relaxation training (.5 h)

Massage (.5 h) Massage (.5 h)

Table 2. Body & Cancer overview

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Aim

In light of the uncertainty surrounding heavy-load lifting in breast cancer survivors at risk for

BCRL, the overall aim of this thesis was to explore the safety of heavy-load resistance exercise

among women at risk of developing BCRL while undergoing adjuvant chemotherapy. To meet this

aim, three studies were undertaken.

The specific aims of the three studies comprising this thesis were:

Study 1 To determine the prevalence of BCRL in breast cancer survivors who had participated

in a six-week multimodal exercise intervention including heavy-load resistance

exercise concomitant to receiving chemotherapy (Body & Cancer). Further, this study

explored associations between engaging in resistance exercise with heavy-loads and

the development of BCRL.

Study 2 To assess the initial lymphatic response to resistance exercise with low-compared to

heavy-load resistance exercise in breast cancer survivors at risk of BCRL, by

comparing acute changes in extracellular fluid, arm volume and BCRL symptoms

after a session of low- and heavy-load resistance exercise in women who had

undergone axillary lymph node dissection and were receiving taxane-based adjuvant

chemotherapy.

Study 3 To prospectively evaluate the effect of a supervised, multimodal intervention

including heavy-load resistance exercise compared with a home-based walking

intervention on BCRL outcomes, muscle strength and breast cancer-specific quality of

life domains in pre-diagnosis physically inactive breast cancer survivors during

adjuvant chemotherapy.

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Material and methods

Each of the three studies was conducted separately with the objective of addressing its specific

research aim. The data collected within each study are not combined, but are summarized to form a

comprehensive whole in the discussion and conclusion sections. Table 3 gives an overview of the

included studies.

Design

Study 1

This PhD was pragmatically formed beginning with a cross-sectional study to determine prevalence

of BCRL and associations with treatment related risk factors and heavy-load resistance exercise,

among former participants of Body & Cancer. While causality cannot be established with this study

design, findings from Study 1was hypothesis generating and provided the platform for the

subsequent studies.

Study 2

Study 2 utilized a randomized, cross-over design to determine the acute lymphatic response to

low- and heavy-load resistance exercise. As between-person variations are inherently eliminated,

this design lends more statistical power with the practical advantage of a smaller sample size,

providing the basis for an efficient comparison between the two resistance exercise loads (62).

While results from this type of study can provide important preliminary information, specifically

about the acute lymphatic response, a longitudinal study is required to determine the longer term

effects of repeated exposure to heavy-load resistance exercise.

Study 3

Study 3 was conducted within the framework of an existing parallel group, randomized trial. The

study evaluated the effect of a multimodal exercise intervention including heavy-load resistance

exercise vs. a walking intervention supported by a pedometer and counselling, with aerobic capacity

as the primary outcome. Therefore, BCRL results are based on secondary outcomes in this trial.

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Study / Paper 1 / I 2 / II & III 3 / IV

Hypothesis Participation in an exercise

intervention utilizing heavy-load resistance exercise would not be

associated with incidence BCRL.

Response would be similar between resistance

exercise loads for all outcomes.

Superior muscular strength and

breast cancer-specific domains after HIGH compared to LOW. BCRL

outcomes will be similar irrespective

of intervention.

Design Cross-sectional study Randomized cross-over trial Parallel-group randomized trial

Participants (n = 149) (n = 21) (n = 153)

Sample Breast cancer survivors who had participated in Body & Cancer during

chemotherapy

Excluded:

BCRL diagnosis prior to Body

&Cancer

Recurrent disease and mortality at study initiation

Women receiving standard adjuvant chemotherapy for stage I-III breast cancer with

no pre-existing cancer diagnosis

Over 18 years of age

Unilateral breast surgery and axillary node

dissection

Excluded: Existing BCRL

Conditions limiting resistance exercise of the

upper extremities Regular heavy resistance exercise (>1 / week)

during the last month

Self-reported physically inactive women receiving adjuvant

chemotherapy for stage I-III breast

cancer.

WHO performance status 0-1

Excluded:

Symptomatic heart disease and/or pathological echocardiogram

Diagnosed acute coronary syndrome

within 6 months Contraindication to exercise

Unable to read or understand

Danish.

Randomized

concealed allocation

Not applicable Yes Yes

Interventions Not applicable One session of low- load resistance exercise One session of heavy-load resistance exercise

HIGH: 12-week supervised, group-based intervention including heavy-

load resistance exercise

OR LOW: 12-week home-based

individual walking intervention to

support physical activity

Measurement

methods

Telephone questionnaire

Medical records

Body & Cancer database

BIS

DXA

NRS

BIS

DXA

NRS Structured interview

1 RM

EORTC QLQ-BR23

Outcomes Self-reported clinically diagnosed

BCRL

Primary: Arm extracellular fluid

Secondary: Inter-arm volume

BCRL symptoms

Arm extracellular fluid

Inter-arm volume

BCRL symptoms Self-reported swelling

Muscle strength

Functional & symptom domains

Blinded Not applicable Data collection & analyses Data collection & analyses

Analysis Prevalence / Associations Equivalence Superiority / Equivalence

Statistics Point prevalence

X2-test Fisher’s exact test

General estimating equation

Confidence interval inclusion

Linear mixed model: heterogeneous

autoregressive (1) covariance Confidence interval inclusion

Table 3. Material and methods overview of the three studies comprising this thesis

Abbreviations: BCRL breast cancer-related lymphedema, WHO World Health Organization, BIS Bioimpedance spectroscopy, DXA Dual X-

ray absorptiometry, NRS Numeric rating scale, RM repetition maximum, EORTC QLQ-BR23 European Organization for Research and

Treatment of Cancer quality of life questionnaire breast-23

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Participants

Study 1

Breast cancer patients who had participated in Body & Cancer between January 2010 and

December 2011 were identified from the Body & Cancer database (n=149). Participants were

eligible for Body & Cancer if they were receiving chemotherapy for cancer at a university hospital

in the Copenhagen area, had a World Health Organization (WHO) performance status of 0-1, and

otherwise had been approved to participate by the treating oncologist. Potential participants for the

cross-sectional analysis were screened for BCRL, recurrent cancer and mortality status in medical

records and excluded if identified. Figure 2 details the recruitment and exclusion process.

Study 2

A convenience sample of women (n =21) receiving adjuvant taxane-based chemotherapy for stage

I-III breast cancer who had undergone ALND, were recruited from the Copenhagen Centre for

Cancer and Health and from a waitlist to participate in Body & Cancer between March 2015 and

December 2016. Potential participants were screened for eligibility (over 18 years of age, unilateral

Figure 2. Flowchart over participants in Study 1

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breast surgery, first diagnosis of breast cancer) and excluded if they had a known clinical diagnosis

of BCRL and/or had conditions limiting resistance exercise of the upper extremities, or had

participated in regular (>1 × / week) upper extremity heavy resistance exercise during the last

month. Those meeting eligibility were then assessed for BCRL after the third cycle of

chemotherapy. Those with evidence of lymphedema (L-Dex >10 assessed using bioimpedance

spectroscopy (BIS) or visual inspection (CTC v3.0) were excluded from participating in the study

and referred to a lymphedema therapist for evaluation and treatment (Figure 3).

Figure 3. Flowchart over participants in Study 2

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Study 3

Participants (n =154) were recruited between January 2014 and July 2016 at the oncology

departments of The Copenhagen University Hospital, Rigshospitalet (RH) and Herlev Hospital

(HE). Women were screened/interviewed for eligibility by nurses / physicians upon initiation of

adjuvant chemotherapy for stage I-III breast cancer. Eligibility criteria included a WHO

performance status of 0-1 and physical activity levels retrospectively rated as less than 150 minutes

of regular, moderate- intensity and / or less than 2 x 20 minutes of high-intensity exercise per week

(Danish national recommendations (63)), three months prior to diagnosis. Eligible participants were

then referred to the research team and matched against exclusion criteria (diagnosed acute coronary

heart syndrome within the past six months, symptomatic heart disease, pathological

echocardiogram, contraindication for exercise noted in medical records, unable to read or

understand Danish) (Figure 4).

Figure 4. Flow chart over participants in Study 3

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Setting

The three studies have been carried out at exercise facilities located at the University Hospitals

Centre for Health Research, University of Copenhagen, Rigshospitalet.

Randomization and blinding

Inherent to exercise studies, participants, nurses and physical therapists delivering the interventions

in Study 2 and 3 were aware of group allocation.

Study 2

Resistance exercise order (low- or heavy-load first) for the experimental sessions was randomly

allocated using a computer-generated random sequence (1:1 ratio). Blinded data collection was

performed by medical technicians at the Department of Clinical Physiology and Nuclear Medicine,

at the Copenhagen University Hospital, Rigshospitalet. Further all DXA scan analyses were

performed blinded to intervention order. Subsequently, data was keyed by research assistants, and

statistical analyses were performed with no knowledge of allocation by an external statistician.

Study 3

Following baseline assessment, participants were sequentially numbered and stratified by age

(<48/48+ years) and hospital (RH/HE). Intervention allocation (1:1) was determined by a

computerized, random number generated at the Copenhagen Trial Unit, an external clinical research

unit. All data collection and subsequent data entry were performed blinded to group allocation by

study staff. Further, all statistical analyses were performed blinded to group allocation by a senior

statistician at the University of Copenhagen.

Interventions

Participants were encouraged to contact study personnel if signs or symptoms of BCRL developed

(Studies 2 and 3) or exacerbation of an existing BCRL (Study 3) occurred during the study period,

and were referred to a lymphedema therapist for evaluation and treatment. The type and duration of

treatment delivered by the therapist was not recorded.

Study 2

Participants completed two familiarization sessions, followed by two experimental sessions (one

low- and heavy-load) lasting approximately 30 minutes, including a 10-minute aerobic-based warm-

up (rowing or cross-trainer) at low-moderate intensity. All sessions were supervised by the author

to ensure consistency of warm-up intensity and order of resistance exercises performed. None of the

participants wore compression sleeves. During the first familiarization session, participants were

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introduced to four upper extremity exercises consisting of the biceps curl (free weights), followed

by the chest press, latissimus pull down and triceps extension using resistance exercise machines

(Technogym®, Gamettola, Italy). Hereafter, a 1 RM strength test was performed for each exercise.

During the second session, one set of 10-15 repetitions was performed, followed by a new 1 RM

strength test. Subsequent resistance exercise prescription during the experimental sessions was

based on these values. Women then participated in the experimental sessions (performed on the

same day of the week and at the same time of day) and were instructed to maintain normal upper-

body activities and to refrain from extraordinary activities involving the upper extremities.

Resistance exercise load corresponded to 60-65% 1 RM (2 sets of 15-20 repetitions) for the low-

load session and 85-90% 1 RM (3 sets of 5-8 repetitions) for the heavy-load session. Participants

were instructed to work to muscle fatigue (until they were unable to maintain appropriate technique)

within the prescribed range, with rest periods of 60-90 seconds between sets.

Study 3

Following baseline testing, all participants received verbal and written information, highlighting

current evidence-based risk factors for developing BCRL (e.g. lymph node removal, BMI, physical

inactivity). Both groups received health promotion counselling including exploration of barriers

and motivators for adopting regular physical activity as well as clinical advice concerning symptom

management and feedback regarding physiological outcomes (64).

HIGH group

Participants randomized to the HIGH group participated in a twelve-week, group-based exercise

program, supervised by a cancer nurse specialist and a physical therapist. The first six weeks

consisted of Body & Cancer (61, 64) followed by six weeks of an ‘All sport’ exercise program. The

‘All sport’ program focused on moderate to high intensity aerobic activities and the high-intensity

components of the previous six weeks (Table 4) (64). The resistance exercise program in Body &

Cancer was carried out as previously described with resistance exercise loads adjusted every third

week, based on new 1 RM testing to ensure progression. If participants developed signs of BCRL or

experienced exacerbations of an existing BCRL, they were instructed to refrain from resistance

exercise targeting the upper extremities or to decrease loads.

LOW group

The LOW group participated in an individualized, home-based, twelve-week walking program

supported by a pedometer and counselling from a cancer nurse specialist or physical therapist

(Table 4). Participants were issued an Omron Walking Style Pro pedometer 2.0, and were

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encouraged to progressively increase steps to ultimately achieve 10,000 steps per day. Face-to-face

meetings during weeks 2, 4, 6, 9 and 12 were held to discuss daily walking targets as well as

barriers and motivators for achieving these targets. Participants were also encouraged to exercise

(beyond walking) and to integrate physical activity into activities of daily living.

Measurement methods/outcomes

Study 1

Medical records

Data regarding surgery and treatment as well as BCRL, recurrent cancer and mortality status were

obtained from electronic medical records.

Structured telephone interview

Structured telephone interviews, lasting 15 minutes on average, were conducted within a six week

period by the PhD student. The primary outcome, a clinical diagnosis of BCRL, was recorded if the

participant answered “yes” to having been diagnosed with lymphedema. Subsequently, participants

were asked when and by whom the diagnosis was made, as well as which region was affected

(hand, arm, breast, torso). Demographic, treatment, and physical activity characteristics were also

HIGH intervention

Monday Tuesday Wednesday Thursday Friday

Part I:Body & Cancer 6 weeks, 9 h/week

Aerobic and resistance

exercise (1.5 h)

Relaxation (0.5 h)

Swedish massage (0.5 h)

Body awareness (1.5 h)

Relaxation (0.5 h)

Aerobic and resistance

exercise (2 h)

Relaxation (0.5 h)

Aerobic and resistance

exercise (1.5 h)

Relaxation (0.5 h)

Swedish massage (0.5 h)

Part II: ‘All-sport’ 6 weeks, 6 h/week

Aerobic and resistance

exercise and e.g.

ballgames, dancing (2 h)

Aerobic and resistance

exercise and e.g.

ballgames, dancing (2 h)

Aerobic and resistance

exercise and e.g. ballgames,

dancing (2 h)

LOW intervention

Week 1

Pedometer Week 2

Pedometer Week 4

Pedometer Week 6

Pedometer Week 9

Pedometer Week 12

Pedometer

consultation consultation consultation consultation consultation consultation

Both interventions

Baseline Week 6 Week 12 Week 39

Health promotion counselling Health promotion counselling Health promotion counselling Health promotion counselling

Table 4. Overview of HIGH and LOW interventions

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obtained as well as any information lacking from the medical records. Specifically, demographic

characteristics included age, current BMI, relationship status, age of children living at home,

education and current occupation. Treatment characteristics included whether surgery had been

performed on the dominant side and whether they had been introduced to breast cancer-specific

post-operative exercises. Behavioral characteristics included whether the participant had performed

post-operative exercises before participating in Body & Cancer, whether they had engaged in

resistance exercise 1-3x/week between surgery and Body & Cancer, and whether they had engaged

in resistance exercise1-3x/week post intervention, and if so for how long, and with what load(s). In

addition, leisure time physical activity was explored using the Salting-Grimby Physical Activity

Level Scale (65).

Arm Circumference measurements

For participants who answered “yes” to having been diagnosed with BCRL, circumference

measurements from the time of lymphedema assessment were obtained from medical records or by

contacting the clinician that had diagnosed BCRL. No standardized protocol for measuring BCRL

was used, with clinicians using measurement protocols ranging from five to seven measuring

points. For this study, a participant was considered to have BCRL if an inter-arm difference of ≥ 2

cm at to two or more measures was reported (66).

Body & Cancer database

Baseline BMI and pre-illness physical activity levels (65) were obtained from the database, as well

as baseline and post-intervention muscular strength (1 RM) of the upper and lower extremities

(chest and leg press, respectively) and adherence to the Body & Cancer program.

Study 2

All outcomes were assessed pre-, immediately post- (within 30 minutes) and 24- and 72-hours post-

resistance exercise sessions.

Extracellular fluid

Bioimpedance spectroscopy (BIS) (SFB7, Impedimed, Brisbane, Australia) was performed

immediately after the DXA scans. This measurement method has a high reliability for detecting

sub-clinical BCRL (67, 68) by directly measuring and comparing the impedance of extracellular

fluid in the upper extremities to electrical currents at a range of frequencies (68). Participants were

positioned in supine with arms and legs slightly abducted with palms facing down. Using the

principle of equipotentials, four single tab electrodes were placed in a tetrapolar arrangement.

Measurement electrodes were placed on the dorsum of the wrist midway between the styloid

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processes. Current drive electrodes were placed five centimeters distally on the dorsal side over the

third metacarpal of the hand, and approximately midway on the third metatarsal on the dorsum of

the foot (69). The ratio of impedance (at R0) between the at-risk and non-affected arm was

calculated and converted into an L-Dex score taking arm dominance into account (70).

Inter-arm volume % difference

Measurements of arm volume were obtained using Dual energy x-ray absorptiometry (DXA) (Lunar

Prodigy Advanced Scanner, GE Healthcare, Madison, WI). DXA measures tissue composition

using a three-compartment model that is sensitive to changes in upper extremity tissue composition

(71). Using previously derived densities for fat (0.9 g/ml), lean mass (1.1g/ml) and bone mineral

content (1.85 g/ml), DXA measurements were converted into estimated arm volumes. Lying supine

on the scan-table with the arm separated from the trunk, each arm was scanned separately. If

necessary, a Velcro band or the free arm was placed over the breast to ensure space between the

arm and trunk. Small animal software (ENCORE version 14.10) was used to analyze the scans as

described by Gjorup et al., (71). All scans were point typed and analyzed by a clinical expert. Inter-

arm volume % differences (at-risk arm minus unaffected arm/unaffected arm * 100) were then

calculated for each participant.

Subjective assessment of BCRL symptoms

The severity of BCRL symptoms (swelling, heaviness, pain, tightness) was monitored using a

numeric rating scale (NRS). Participants rated their perception of symptoms for each arm on a scale

from 0 (no discomfort) to 10 (very severe discomfort) (72, 73).

Study 3

All outcomes were assessed at baseline, 12 week follow-up (immediately post-intervention) and 39

week follow-up. 1 RM strength and self-reported data were also assessed at these time points as

well as at 6 weeks post-baseline.

Extracellular Fluid

BIS was performed immediately after DXA as described in Study 2, and was consecutively

obtained from participant 71 forward.

Inter-arm volume % difference

Arm volume was obtained using DXA. Lying supine on the scan-table with arms slightly abducted

and hands in a mid-prone position, total body scans were performed fasting, at the same time of day

(mornings) at all assessments. Scans were automatically analyzed using encore version 16, GE

Healthcare Lunar software. From the total body scans, the measured weight of fat, lean mass and

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bone mineral content of both arms were identified and converted into estimated arm volumes as in

Study 2 with the region of interest extending from the gleno-humeral joint to the finger tips (74,

75). Inter-arm volume % differences (at-risk arm minus unaffected arm/unaffected arm * 100) were

then calculated for each participant.

Self-reported BCRL symptoms

The severity of BCRL symptoms (heaviness, tightness, pain, swelling) on the surgical side was

monitored using a NRS. Participants rated their perception of symptoms on the surgical side as

compared to the non-surgical side on a scale from 0 (no discomfort) to 10 (very severe

discomfort)(72).

Self-reported swelling

Participants reported if they had observed a difference in size between their surgical-and non-

surgical side within the last week. If they answered “yes”, they were then asked to report where:

fingers, hand, forearm, upper arm (extremity) and breast, torso (body).

Upper extremity muscular strength

To assess maximal strength of the upper extremities, the 1 RM strength test (51) was performed

using the chest press (Technogym®, Gamettola, Italy). Prior to the 1 RM attempt, a warm-up was

performed consisting of 8-10 repetitions using a low weight ensuring no muscle fatigue. Hereafter,

load was increased based on ease of performance, with one repetition lifted of each load, until the

participant was unable to lift a respective load.

Breast cancer-specific functional and symptom domains

To assess breast cancer-specific quality of life domains (functional and symptom), the 23 item

European Organization for Research and Treatment of Cancer (EORTC) breast cancer module

(BR23) (76), version 3.0, was used. This validated breast cancer-specific module includes four

functional scales as well as four symptom specific subscales. Each item is scored on a four point

Likert scale from “not at all” to “very much”, with raw scores summed and converted to a score out

of 100. Higher levels of functioning are represented by higher functional scores and worse

symptoms are represented by higher symptom scores (76, 77).

Data analysis

Statistical assistance was provided by associate professor, senior statistician Karl B. Christensen

(Department of Biostatistics, University of Copenhagen) for all three studies, with additional

assistance from PhD Megan L. Steele (Institute of Health and Biomedical Innovation, Queensland

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University of Technology) in study 2. A two-tailed P < .05 was taken as evidence of statistical

significance.

Study 1

Statistical analysis was performed using the Statistical Package for Social Sciences (SPSS) software

(version 19) for Windows. Descriptive statistics are presented as counts (percentages) for

categorical variables and as means and standard error (SE) for continuous variables unless

otherwise noted. Mean changes in 1 RM muscular strength post Body & Cancer were assessed

using a paired t-test, and were analyzed on a per-protocol basis, (only participants with data at

baseline and 6 weeks) as well as on an intention to treat (ITT) basis using baseline observation

carried forward. Point prevalence of BCRL was calculated on average 14 months post intervention

(range 4 to 26 months)), and estimated retrospectively at the commencement of Body & Cancer as

well as 1, 2, 3, and 4 months post Body & Cancer.

To compare differences between participants diagnosed with BCRL and those

without, Chi-squared and Fisher’s exact test were used for categorical variables and two-sample t-

tests for continuous variables. Levene’s test for equality of variances was performed and results

presented use pooled variances unless otherwise noted.

Study 2

Sample size calculation was based on changes in L-Dex scores between baseline and 72-hours post-

resistance exercise sessions. On the basis of clinical experience with patients with BCRL a change

score of 2.0 L-Dex units was considered clinically relevant, and SD of the distribution of L-Dex

units was estimated at 1.9 units based on results of Cormie et al.(12). However, upon study

initiation no normative data existed in the at-risk population nor did a threshold for a clinically

significant acute change. As such, a change in 2.0 L-Dex units was deemed too small in the at-risk

population, based on the assumption that larger fluctuations would be seen within the normal range.

Therefore, a priori, the clinically relevant threshold was set at 3.0 L-Dex units. Eighteen

participants were needed to be 90% sure that the limits of a two one-sided 95% confidence interval

(CI) would exclude a difference in means of more than 3.0 L-Dex units. To allow for drop-outs, 21

women were recruited.

Descriptive statistics included counts (and percentages) for categorical values and

mean ± standard deviation (SD) for normally distributed continuous variables, unless otherwise

noted. Individual responses to resistance exercise loads were first assessed descriptively, including

determination of the proportion that exceeded the predetermined clinically relevant threshold. Next,

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generalized estimating equations (GEE) (78) were used to evaluate the effects of time (pre-, post-,

24- and 72-hours post) and load (low-/heavy-load), and a time x load interaction. An exchangeable

correlation structure was used to model the within-subject correlation of repeated measurements

over time and across intensities.

To assess equivalence, a priori, equivalence margins were determined for all

outcomes. For extracellular fluid, the margin of equivalence was set at ± 3.0 L-Dex units (primary

outcome). An equivalence margin of ±3.0% was used for inter-arm volume % differences based on

findings from Stout et al., (79) showing that volume increases of >3% from pre-operative measures

were indicative of subclinical BCRL. For all BCRL symptoms, inter-arm differences were

calculated and an equivalence margin was set at ±1.0 points based on previous findings that suggest

a 2 point or 30% change to be clinically meaningful for pain (72). The principle of confidence

interval inclusion was used to calculate two one-sided upper and lower 95% confidence limits for

all outcomes (80) (reported as two-sided 90% confidence limits). If the interval between the upper

and lower confidence limits was within the predetermined equivalence margin, equivalence

between resistance exercise intensities was declared. Per-protocol principles were applied as this is

considered the most conservative approach for determining equivalence (81). Analyses were

conducted in R version 3.3.1 (82) using geepack 1.2.0.1 for GEE modelling (83).

Study 3

Analyses were conducted using Statistical Analysis Software (SAS) version 9.4.

Descriptive statistics included counts (and percentages) for categorical variables and point

prevalence of BCRL defined as L-Dex > 10, inter-arm volume difference > 5% or self-reported

observation of swelling. For continuous variables means ± SD (normally distributed), or median

with interquartile range (IQR) (not normally distributed) are presented.

Linear mixed models with a heterogeneous autoregressive (1) covariance structure

were used to estimate changes over time in each group with an intention-to-treat (ITT) approach.

An exchangeable correlation structure modelled the within-subject correlation of repeated

measurements over time and across interventions, incorporating all available data including

participants with incomplete data. Effect sizes were calculated for muscular strength (84). A two-

sided significance level was set at 0.05 for outcomes where superiority was hypothesized (muscular

strength and cancer-specific functional and symptom domains).

As with Study 2, a priori, clinically relevant equivalence margins were chosen for BCRL outcomes.

For L-Dex, the margin of equivalence was set at ±5.0 units based on new normative data indicating

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37

that L-Dex scores fluctuate between 9-11 units (70). An equivalence margin of ±3.0% was used for

inter-arm volume % differences and at ±1.0 points for BCRL symptoms, and the principle of

confidence interval inclusion (80) was used to calculate two one-sided upper and lower 95%

confidence limits, (reported as 90% confidence limits) as in study 2. Further, a per-protocol analysis

of participants with an adherence rate >65% to the HIGH intervention was performed to evaluate

equivalence of BCRL outcomes to the predetermined equivalence margins.

Ethical approval

Study 1

Study 1 was performed in accordance with the Helsinki Declaration, and approved by the Danish

Data Protection Agency.

Study 2

Study 2 was registered at Current Controlled Trials (ISRCTN97332727), approved by the Danish

Data Protection Agency (30-1430) and the Danish Capital Regional Ethics Committee (H-3-2014-

147).

Study 3

Study 3 was registered at Current Controlled Trials (ISRCTN24901641), approved by the Danish

Data Protection Agency (2011-41-6349) and the Danish Capital Regional Ethics Committee (H-1-

2011-131).

Results

The following section presents the main findings of the three studies.

Study 1

Participants

The mean age of participants was 47.7 years and mean self-reported BMI was 24.1, with 54 (36%)

classified as overweight (BMI > 25). The majority reported being physically active before diagnosis

108 (72%). All had undergone chemotherapy, with 141 (95%) having received adjuvant taxane-

based chemotherapy, 62 (42%) had received a mastectomy and 90 (60%) had ALND while 120

(81%) had received radiotherapy.

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Body & Cancer participation

Over half of the participants (60%) had an adherence rate of at least 70% (17 of 24 training days).

Significant increases in lower and upper extremity muscular strength were observed after six weeks

of training (Table 5).

Total Population Total Population ALND Population

Baseline 6 weeks Change No BCRL BCRL No BCRL BCRL

1 RM (kg) n Mean (SE) Mean (SE) Mean (SE) n ∆ Mean (SE) n ∆ Mean (SE) n ∆ Mean (SE) n ∆ Mean (SE)

Chest Press 125 27.2 (.66) 31.9 (.70) 4.7 (.43) 93 4.6 (.47) 32 5.0 (.98) 41 4.3 (.69) 31 4.5 (.88)

Leg Press 132 76.0 (2.00) 94.8 (2.45) 18.8 (1.75) 96 16.5 (1.82) 36 24.7 (4.07) 45 14.9 (2.48) 35 23.7 (4.06)

BCRL point prevalence

At an average follow-up of 14 months (range 4-26) post Body & Cancer, point prevalence of BCRL

was 27.5% for the total sample (n=149). When analysis was restricted to include only women who

underwent ALND, point prevalence was 44.4% (Table 6). Six percent of the total sample and 10%

of those who underwent ALND reported that they had been diagnosed with BCRL during the

intervention, with an additional 11.4% and 17.8% diagnosed within the first four months post Body

& Cancer, respectively. All BCRL cases had ALND, with the exception of one participant (n = 89,

98.8%). Of the participants with a diagnosis of BCRL, one reported swelling in the hand only, three

in the breast only, and one in the torso only. The remainder (n = 144) reported swelling in the arm

only or in combination with the hand, breast and torso.

Arm circumference measurements were obtained for 38 of the 41 (93%) participants

diagnosed with BCRL, from two hospitals and six private practice lymphedema therapists. Of these,

47.4% had an inter-arm difference ≥ 2 cm at two or more measures. Therefore, when applying this

measurement method and cut-off, prevalence rates were lower than for those diagnosed with BCRL

(Table 6).

Table 5. Muscular strength post Body & Cancer

∆ Change between baseline and post Body & Cancer, Bold (p-value <0.05), No BCRL as reference

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BCRL vs. No BCRL

When comparing characteristics of participants with and without diagnosed BCRL, significantly

more (p < 0.05) participants with BCRL currently had a BMI > 25 (BCRL 21 (51%) vs. No BCRL

33 (31%), had undergone ALND (BCRL 40 (98%) vs. No BCRL 50 (46%)) and had received

radiotherapy (BCRL 39 (95%) vs. No BCRL 81 (75%)). No between group differences were

observed in regard to resistance exercise participation before or after Body & Cancer, nor to

adherence to Body & Cancer, or to changes in muscular strength (Table 5).

A sub-analysis of participants with ALND showed that significantly more (p < 0.05)

participants with BCRL were currently overweight or had been overweight upon commencing Body

& Cancer (Table 7). No between group differences were found in regard to radiotherapy, however

93.3% of the participants with ALND had received radiotherapy. No between group differences

were seen in regard to RE participation before or after Body & Cancer (Table 7), nor to changes in

muscular strength (Table 5).

Time in relation to participation in

Body & Cancer Diagnosed BCRL

Total population

(n = 149)

Circumference ≥ 2

Total population

(n = 146)†

Diagnosed BCRL

ALND population

(n = 90)

Circumference ≥ 2

ALND population

(n = 87)†

During intervention 9 (6.0) 5 (3.4) 9 (10.0) 5 (5.8)

Within 1month post intervention 16 (10.7) 10 (6.8) 16 (17.8) 10 (11.5)

1-2 months post intervention 21 (14.1) 11 (7.5) 21 (23.3) 10 (11.5)

2-3 months post intervention 23 (15.4) 13 (8.9) 23 (25.6) 12 (13.7)

3-4 months post intervention 26 (17.4) 15 (10.3) 25 (27.8) 14 (16.1)

Total at study* 41 (27.5) 18 (12.3) 40 (44.4) 17 (19.5)

Table 6. Point prevalence of lymphedema in relation to participation in Body & Cancer. Values are

numbers of participants (%).

*On average 14 months (4-26) post Body & Cancer. † Circumference measurements not available for 3 participants

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No BCRL

(n = 50)

BCRL

(n = 40)

Demographic characteristics p

Age (years) mean (SD) 49.2 (9.0) 47.8 (8.0) .436

Children in care < 7 years 9 (18.0) 4 (10.0) .371

Married, cohabitating or in a relationship 37 (74.0) 28 (70.0) .813

Education > secondary school 44 (88.0) 37 (92.5) .726

Employed (full/part time) 40 (80.0) 29 (72.5) .458

Not physically demanding work 27 (54.0) 19 (47.5) .832

Moderately physically demanding work 11 (22.0) 9 (22.5)

Very physically demanding work 2 (4.0) 1 (2.5)

Health and medical characteristics

Baseline BMI (kg/m2) > 25* 13 (26.0) 20 (51.3) .017

Study BMI (kg/m2) > 25 9 (18.0) 21 (52.5) .001

Mastectomy 25 (50.0) 18 (45.0) .676

Non-dominant arm 32 (64.0) 23 (57.5) .664

Chemotherapy

3-wkly CE x 3 -> 3 wkly docetaxel x 3 33 (66.0) 29 (72.5) .508

3-weekly CT x 6 13 (26.0) 10 (25.0)

Other 4 (8.0) 1 (2.5)

Received radiotherapy 46 (92.0) 38 (95.0) .689

Received endocrine treatment 45 (90.0) 33 (82.5) .358

Received trastuzumubab 8 (16.0) 2 (5.0) .175

Physical activity level (self-reported)

Pre-illness†

Sedentary 1 (2.1) 1 (2.8) .717

Walking or cycling for pleasure 11 (22.9) 9 (25.0)

Regular physical exercise, at least 3 h/week 34 (70.8) 23 (63.9)

Intense physical activity > 4 h/week 2 (4.2) 3 (8.3)

Present

Sedentary 0 (0.0) 1 (2.5) .326

Walking or cycling for pleasure 7 (14.0) 10 (25.0)

Regular physical exercise at least 3 h/week 25 (50.0) 15 (37.5)

Intense physical activity > 4 h/week 18 (36.0) 14 (35.0)

Training

Performed exercises prescribed post-surgery‡

No 10 (21.7) 3 (7.7) .192

3 x weekly 8 (17.4) 7 (17.9)

Daily 28 (60.9) 29 (74.4)

RE 1-3x/wk between surgery and Body & Cancer ‡ 13 (28.3) 10 (25.6) 1.000

RE 1-3x/wk 3 months after Body & Cancer 24 (48.0) 22 (55.0) .532

Utilized 2-3 sets of 5-8 RM 14 (28.0) 14 (35.0) .769

Adherence ≥70% while in Body & Cancer 35 (70.0) 19 (47.5) .051

Table 7. BCRL vs. no BCRL in participants with ALND (n = 90). Values are numbers (%)

unless stated otherwise.

Abbreviations: CE, cyclophosphamide & epirubicin; CT, cyclophosphamide & docetaxel; RE, resistance

exercise *(n = 84, (n = 39 BCRL; n = 50 no BCRL) due to missing data. †(n = 84) due to missing data.‡ (n =

85,(n = 39 BCRL; n = 46 no BCRL) participants receiving neo-adjuvant (n = 4) or chemotherapy for advanced

disease (n = 1) not included.

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Study 2

Participants

Twenty one eligible participants were included in the study with seventeen (81%) completing all

data collections. For details of participant flow see Figure 4. Characteristics of the study population

are presented in Table 8. As per eligibility criteria, all participants received adjuvant taxane-based

chemotherapy during the experimental sessions. However, as standard chemotherapy changed

midway through the study period, the first ten participants received docetaxel, while the last 11

received paclitaxel.

Variables Mean ± SD / Median (range)

Age (years) 45.3 ± 9.2 / 46 (23-60)

BMI (kg/m2) 25.3 ± 4.7

Cancer stage n (%)

ll 15 (71)

lll 6 (29)

Tumor size (mm) 21.5 ± 12.9 / 18 (7-62)

Breast surgery n (%)

Lumpectomy 8 (38)

Mastectomy 13 (62)

Surgery on dominant side n (%) 11 (52)

Axillary lymph nodes removed 21.7 ± 7.8

Metastatic lymph nodesa 5.7 ± 7 / 2 (1-25)

Seroma drainage n (%) 5.5 ± 3.4

Chemotherapy n (%)

3-wkly CE x 3 -> 3 wkly docetaxel x 3 10 (48)

3-wkly CE x 3 -> 1 wkly paclitaxel x 9 11 (52)

Axillary webbing at screening n (%) 8 (38)

L-Dex at screening -0.08 ± 2.23

Table 8. Characteristics of participants (n = 21)

Abbreviations: CE, cyclophosphamide & epirubicin a) micro- and macrometastases

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42

Individual responses to resistance exercise

Individual responses to resistance exercise sessions varied with no apparent group trend observed

for L-Dex and inter-arm volume % differences (Figure 5A, 5B). For BCRL symptoms, most

participants were asymptomatic pre-exercise and remained asymptomatic throughout the

subsequent data collections irrespective of loads lifted (Figure 5C-F).

Subplot A Heavy-load L-Dex pre-, post-, 24-hours (n = 18); Sub-plots C-F Heavy-load breast cancer-related

lymphedema symptoms pre- and post- exercise (n = 18), Sub-plots C-F (n=) refers to the number of participants

with a symptom score of 0 at all time points.

Figure 5. Individual responses related to low- and heavy-load resistance exercise (n = 17)

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L-Dex

The estimated mean difference between resistance exercise loads and associated two-sided 90% CIs

were within the predetermined equivalence margin of ±3.0 L-Dex units immediately-, and 24-hours

after resistance exercise indicating equivalence between intensities (Table 9). However, at 72-hours

post-exercise, the lower CI exceeded -3.0 and equivalence between low- and heavy-load intensities

could not be declared, indicating a reduction of extracellular fluid post heavy-load resistance

exercise.

Inter-arm volume % difference

Equivalence between resistance exercise loads was observed at all time points for inter-arm volume

% differences, as estimated mean differences and 90% CI were within the ±3.0 margin of

equivalence (Table 9).

BCRL symptoms

Equivalence between resistance exercise loads was found for all BCRL symptoms at all time points,

as estimated mean differences and associated 90% CIs were within the equivalence margin of ±1.0

(Table 9).

Adverse events

No adverse events related to exercise (i.e. sprains or strains) were reported. Two (11%) participants

were advised to seek evaluation by a lymphedema therapist at the end of the study period as L-Dex

scores had exceeded ten (Figure 5A). One participant had a pre-exercise L-Dex score of 7.9 in

week one which remained elevated at week two, with a pre-exercise L-Dex score of 11.7 that

decreased over the subsequent data collections. The other participant initiated the heavy-load

session at week one with a pre-exercise L-Dex score of 3.8, and subsequent measures fluctuating

below 5.0 units. At week two, the pre-exercise L-Dex score had increased to 9.5 that further

increased to 12.7 post-exercise, followed by decreasing subsequent measures. Notably, this

participant suffered from rapid weight gain due to generalized edema between weeks one and two

that was effectively treated with diuretics. All other outcomes were within the predetermined

clinical thresholds at all time points for both of these participants.

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Estimated mean differenceb

Equivalence 90% CI

L-Dex (±3.0)a

Post- exercise -0.97 -2.09 to 0.16

24-hrs Post-exercise -0,14 -1.63 to 1.35

72-hrs Post-exercise -1.00 -3.17 to 1.17c

Inter-arm volume % difference (±3.0)a

Post- exercise 0,21 -0.89 to 1.31

24-hrs Post-exercise 1,09 0.41 to 1.78

72-hrs Post-exercise 0,96 -0.09 to 2.02

Inter-arm difference Pain (±1.0)a

Post- exercise 0 -0.43 to 0.43

24-hrs Post-exercise -0.06 -0.58 to 0.46

72-hrs Post-exercise -0,06 -0.61 to 0.49

Inter-arm difference Heaviness (±1.0)a

Post- exercise 0,24 -0.23 to 0.70

24-hrs Post-exercise 0,18 -0.32 to 0.67

72-hrs Post-exercise 0,24 -0.38 to 0.85

Inter-arm difference Tightness (±1.0)a

Post- exercise -0,06 -0.45 to 0.34

24-hrs Post-exercise -0.11 -0.50 to 0.27

72-hrs Post-exercise 0.20 -0.37 to 0.77

Inter-arm difference Swelling (±1.0)a

Post- exercise 0 -0.33 to 0.33

24-hrs Post-exercise 0 -0.33 to 0.33

72-hrs Post-exercise 0.06 -0.42 to 0.54

Table 9. Equivalence between resistance exercise intensities (n = 17)

aEquivalence margin. b Estimated mean difference calculated using a generalized estimating equations model with heavy-

load as comparator (heavy minus low). c equivalence not demonstrated

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45

Study 3

Participants

391 women receiving adjuvant chemotherapy for breast cancer were screened for eligibility with

153 (39%) included in the study between January 2014 and July 2016 (Figure 4). Baseline

characteristics were balanced between the two intervention groups (Table 10). However, more

participants with L-Dex data had received paclitaxel based chemotherapy (13 (20.3%) vs. 6 (6.7%).

Further, the mean BMI of participants without inter-arm volume data was higher than participants

with, as body dimensions exceeded the DXA scan area (31.3 ± 5.3 vs. 24.3 ± 3.6, respectively).

Characteristics Total (n = 153) HIGH (n = 75) LOW (n = 78)

Age (years), mean ± SD 51.7 ± 9.4 51.5 ± 9.6 52.0 ± 9.3

BMI (kg/m2), mean ± SD 26.1 ± 5.1 26.2 ± 5.3 26.0 ± 4.9

Cancer stage, n (%)

Stage 1

Stage 2

Stage 3

56 (36.6%)

81 (52.9%)

16 (10.5%)

31 (41.3%)

36 (48.0%)

8 (10.7%)

25 (31.1%)

45 (57.7%)

8 (10.3%)

Breast surgery, n (%)

Lumpectomy

Mastectomy

Mastectomy plus expander

90 (58.8%)

56 (36.6%)

7 (4.6%)

47 (62.7%)

26 (34.7%)

2 (2.7%)

43 (55.1%)

30 (38.5%)

5 (6.4%)

Axillary surgery, n (%)

Axillary lymph node dissection

Sentinel node biopsy

61 (39.9%)

92 (60.1%)

26 (34.7%)

49 (65.3%)

35 (44.9%)

43 (55.1%)

Nodes removed, median (IQR) 3 (2-17) 3 (1-15) 5 (2-19)

Surgery on dominant side,* n (%) 76 (49.7%) 39 (52.0%) 37 (47.4%)

No. of seroma drainages, median (IQR) 1 (0-5) 1 (0-5) 1 (0-5)

Chemotherapy, n (%)

3-wkly CE x 3 -> 3 wkly docetaxel x 3

3-wkly CE x 3 -> 1 wkly paclitaxel x 9

Other

130 (85.0%)

19 (12.4%)

4 (2.6%)

66 (86.7%)

8 (10.7%)

1 (1.3%)

64 (82.1%)

11 (14.1%)

3 (3.9%)

Observations of swelling,** n (%)

Extremity (hand, underarm, overarm)

Body (breast, torso)

Both (body & extremity)

5 (3.3%)

31 (20.5%)

11 (7.3%)

2 (2.7%)

14 (18.9%)

3 (4.1%)

3 (3.9%)

17 (22.1%)

8 (10.4%)

Treatment related to lymphedema,** n (%)

Preventatively

Existing lymphedema

4 (2.6%)

5 (3.3%)

1 (1.4%)

1 (1.4%)

3 (3.9%)

4 (5.2%)

Symptom subscales EORTC-BR23

Arm symptoms, n, mean ± SD

Breast symptoms, n, mean ± SD

152, 16.2±19.0

151, 18.9±16.1

74, 15.6±20.1

74, 18.6±16.4

78, 16.8±18.0

77, 19.2±16.0

L-Dexa, n, Mean ± SD 80, -0.3±5.1 39, -0.6±3.6 41, 0.1±6.2

Volume % differenceb, n, mean ± SD 118, 1.3±19.8 55, 0.6 ±19.7 63, 1.9±20.0

Upper extremity strengthc, n, mean ± SD 138, 29.4±8.3 71, 29.0±8.1 67, 29.8±8.

Table 10. Baseline charactereristics (n = 153)

Not included: *n = 4 missing, **n = 2 missing, a n=3 (n = 1 missing, n = 2 bilateral axillary surgery), b n =35 (n = 5 bilateral

axillary surgery, n = 30 left side estimated), c n = 15 (n = 14 post-surgery restrictions, n =1 precautionary due to arm swelling)

Abbreviations: BMI, body mass index; SD, standard deviation; CE, cyclophosphamide & epirubicin; pctl, percentile/IQR,

interquartile range

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Retention, adherence and adverse events

Outcome data were available for 130 participants (85%) at 12-weeks post-intervention, and for 121

(79%) at the 39 week follow-up (Figure 1). %). Four women never partook in the intervention and

an additional six withdrew shortly after initiation of the program. A detailed description of reasons

for non-attendance can be found elsewhere (article in submission, Møller et al.).

On average, participants in the HIGH group attended 66% (±18) of the planned

exercise sessions. Adherence to resistance exercise prescription of the upper extremity

corresponded to a median load of 10 RM during the first two weeks. From week three forward

(heavy-load period), loads corresponded to 7 RM. Comparatively, loads lifted for the leg press were

14 RM and 8 RM, respectively. No exercise-related injuries were reported. Six participants in the

HIGH and five participants in the LOW group experienced swelling during the 12-week

intervention and received treatment delivered by a lymphedema therapist. Just one of the women in

the HIGH group reduced loads (10-15 RM), whereas the other five continued lifting loads

corresponding to 5-8 RM. Seven of these participants had received treatment for BCRL between

the 12 and 39 week follow up, while three had not, and one was lost-to follow-up at 39 weeks.

Lymphedema

Point prevalence: Irrespective of assessment method, point prevalence of BCRL was similar

between the HIGH and LOW group at all time points (Table 11). Point prevalence of BCRL varied

depending on the method of assessment. For participants reporting an observation of swelling on

the surgical side compared to the non-surgical side, it is worth noting that body only (breast and

torso) accounted for 31 (66%), 8 (25.8%) and 17 (39.5%) of these cases at baseline, 12 and 39

weeks respectively. As BIS and DXA detect arm and hand swelling only, these methods of

lymphedema were unable to detect these cases (Table 11).

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Self-reported diagnosis of BCRL at baseline: Five participants (3.3%) reported a diagnosis

of BCRL which they were receiving or had received lymphedema treatment for; one of whom

participated in the HIGH group and carried out the resistance exercise protocol without need for

modification (e.g. less load). All five of these participants also reported observed swelling at

baseline, two of whom reported localization to the torso only, which therefore could not be detected

by BIS or DXA. Further, no DXA measurements were available for two participants as body

dimensions exceeded the scan areas. Comparatively, one of these participants had an L-Dex >10,

while no L-Dex was available for the other participant. Finally, one of the participants reported

observed swelling of the overarm, breast and torso which BIS and DXA did not detect.

L-Dex: The mean difference in L-Dex scores between the HIGH and LOW group and associated

two-sided 90% CIs were contained within the predetermined equivalence margin of ±5.0 units at

both 12 and 39 weeks indicating equivalence between groups (Table 12). Equivalence to the

predetermined equivalence margin in the per-protocol analysis at 12 weeks was also observed

(Table 13). However, at the 39 week follow-up, the upper CI exceeded the predetermined margin.

n Baseline n 12 weeks n 39 weeks

L-Dex >10a

HIGH

LOW

39

41

0 (0.0%)

2 (4.9%)

33

31

3 (9.1%)

2 (6.5%)

41

34

4 (9.8%)

3 (8.8%)

Inter-arm volume % difference > 5%b

HIGH

LOW

55

63

15 (27.3%)

15 (23.8%)

45

51

14 (31.1%)

13 (25.5%)

50

49

12 (24.0%)

13 (26.5%)

Observed difference in size between sides within the last weekc

HIGH

LOW

74

77

19 (25.7%)

28 (36.4%)

62

63

18 (29.0%)

13 (20.6%)

62

59

21 (33.9%)

22 (37.3%)

Based on all available data for each outcome.a Maximum n = 81 due to bilateral axillary surgery (n =2) and

BIS not available (n = 70). At 39 weeks BIS was available for twelve of these particicpants and included in

the analysis ; b Maximum n = 148 due to bilateral axillary surgery (n = 5), n = 30, 28, 14 exceeded DXA

scan area, respectively at baseline, 12 and 39 weeks and were therefore not included in the analysis); c Of

the participants that observed swelling at: baseline n = 31 (66%), 12 weeks n = 8 (25.8%), 39 weeks n = 17

(39.5%) reported swelling located to the body (breast , torso) only

Table 11. Lymphedema point prevalence. Number of participants (%)

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Inter-arm volume % difference: Non-equivalence between groups was observed at all time

points for inter-arm volume % differences with deviations inconclusive or indicating reductions in

arm volume, favoring the HIGH group (Table 12). These observations were consistent with findings

from the per-protocol analysis (Table 13).

BCRL symptoms: Equivalence between groups was found for all symptoms except for pain at 12

weeks and tightness and pain at 39 weeks favoring reductions for those in the HIGH group (Table

12). Consistent with the between group analysis, the per-protocol findings indicated equivalence to

the predetermined margin or deviations indicating reductions in symptoms except for pain at 39

weeks as upper CI’s exceeded the equivalence margin (Table 13).

Mean difference*

Equivalence 90% CI

L-Dex (±5.0)a (n =81)** n

12 weeks 64 0.4 -2.5 to 3.2

39 weeks 63 0.7 -2.2 to 3.6

Inter-arm volume % difference (±3.0)a (n =148)**

12 weeksǂ 86 -3.5 -17.3 to 10.3b

39 weeksǂ 83 -1.7 -7.7 to 4.3c

Pain (±1.0)a

(n =153)**

12 weeks 124 -0.7 -1.3 to 0b

39 weeks 121 -0.8 -1.5 to -0.1b

Heaviness (±1.0)a

(n =153)**

12 weeks 124 -0.2 -0.6 to 0.2

39 weeks 121 0.0 -0.7 to 0.6

Tightness (±1.0)a

(n =153)**

12 weeks 124 -0.1 -0.8 to 0.6

39 weeks 121 -1.0 -1.8 to 0.2b

Swelling (±1.0)a

(n =153)**

12 weeks 124 0.2 -0.4 to 0.8

39 weeks 120 0.0 -0.8 to 0.7

Table 12. Equivalence between groups for BCRL outcomes

*Mean difference between groups with HIGH as comparator (HIGH minus LOW); **Maximum n; ǂn = 38 and 30 not included at 12 and 39 weeks respectively, due to body dimension exceeding the

DXA scan area; aPre-determined equivalence margin; Bold = equivalence not demonstrated; bnegative deviation reflecting reductions beyond the equivalence margin favoring the HIGH group cinconclusive as mean is within predetermined equivalence margin, but CI’s exceed at both sides

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Variable Baseline 12 weeks 39 weeks 12 weeks - baseline 39 weeks-baseline

Mean (SD) Mean (SD) Mean (SD) n Δ (90 % CI) n Δ (90 % CI)

L-Dex (±5.0)a

-0.8 (3.3) 0.9 (6.6) 1.5 (5.3) 21* 1.7 (-0.8 to 4.2) 21* 3.2 (0.9 to 5.5)c

Inter-arm volume %

difference (±3.0)a

5.3 (23.0) 4.3 (27.2) 0.6 (7.4) 21** -3.1 (-19.5 to 13.4)b 26** -5.0 (-12.8 to 2.9)b

Pain (±1.0)a

1.0 (1.7) 0.6 (1.2) 1.4 (2.5) 32 -0.4 (-0.9 to 0.1) 33 0.4 (-0.4 to 1.2)c

Heaviness (±1.0)a

0.5 (1.3) 0.3 (1.1) 0.9 (1.7) 32 -0.2 (-0.4 to 0.1) 33 0.4 (0.0 to 0.8)

Tightness (±1.0)a

1.6 (2.4) 0.8 (1.9) 0.4 (0.8) 32 -0.9 (-1.5 to -0.2)b 33 -1.2 (-2.0 to -0.5)b

Swelling (±1.0)a

1.1 (2.0) 1.0 (1.8) 1.0 (1.8) 32 -0.1 (-0.7 to 0.6) 33 -0.1 (-0.6 to 0.5)

Upper extremity muscular strength

A significant (p < 0.05) increase in maximal upper extremity strength was observed in the HIGH

group at all follow-up assessments which were significantly greater compared to those in the LOW

group at 6 and 12 week follow-up (Table 14). Strength increases corresponded to an effect size of

0.55 (95% CI 0.40 – 0.75), 0.55 (0.35 – 0.70) and 0.35 (0.15 – 0.55) at 6, 12 and 39 weeks,

respectively.

Breast cancer-specific functional and symptom domains

No between group differences were observed for any subscale score of the EORTC QLQ-BR23.

However, both groups reported declines in breast symptoms at 6 and 12 weeks. Similarly, declines

in arm symptoms were seen for both groups at 6 weeks, but only in the HIGH group at 12 week

follow-up (Table 14 and Supplemental table).

Table 13. Per-protocol equivalence of BCRL outcomes in participants with >65% adherence to HIGH

a Pre-determined equivalence margin; *maximum n = 21; Bold = equivalence not demonstrated;**maximum n = 32; b negative

deviation reflecting reductions beyond the equivalence margin; c positive deviation reflecting increases beyond the equivalence

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Δ 6 weeks-baseline Δ 12 weeks-baseline Δ 39 weeks-baseline

Variable n

Mean Δ

(95% CI)

Group difference

(95% CI) n

Mean Δ

(95% CI)

Group difference

(95% CI) n

Mean Δ

(95% CI)

Group difference

(95% CI) Muscular strength 1 RM (kg)*

Chest press

HIGH LOW

58 51

5 (3 to 6)

1 (-1 to 2)

4 (2 to 6)

56 55

4 (3 to 6)

1 (0 to 3)

3 (1 to 5)

50 44

3 (1 to 5)

1 (-1 to 3)

2 (0 to 5)

EORTC QLQ-BR23 scores**

Body Image HIGH

LOW

62

61

2 (-3 to 7)

-1 (-6 to 3)

4 (-3 to 10)

60

62

-3 (-9 to 2)

-6 (-11 to -1)

2 (-5 to 10)

61

56

7 (2 to 11)a

6 (1 to 11)a

1 (-6 to 8)

Systemic therapy ǂ HIGH

LOW

63

62

5 (1 to 10)a

4 (-1 to 9)

1 (-6 to 8)

61

65

7 (2 to 12)a

9 (4 to 14)a

-2 (-9 to 6)

61

57

-19 (-23 to -15)b

-20 (-24 to -16)c

1 (-5 to 7)

Breast symptoms HIGH

LOW

62

62

-6 (-9 to -2)a

-7 (10 to -3)a

1 (-4 to 6)

60

64

-11 (-15 to -7)b

-9 (-12 to -5)a

-2 (-8 to 3)

59

55

-4 (-9 to 1)

1 (-4 to 6)

-4 (-12 to

3)

Arm symptoms HIGH

LOW

62

62

-4 (-8 to 0)a

-5 (-10 to -1)a

1 (-5 to 7)

60

65

-6 (-10 to -1)a

-4 (-8 to 1)

-2 (-8 to 4)

59

56

-1 (-6 to 4)

3 (-2 to 9)

-4 (-12 to

3)

Discussion This thesis examined for the first time whether participation in heavy-load resistance exercise

exacerbates development of lymphedema in breast cancer survivors at risk for lymphedema. This

section provides a discussion of the main findings of the three studies/ four articles considered in

the context of relevant literature. Further, methodological considerations including issues of internal

and external validity will be addressed.

Lymphedema

Findings of Study 1 indicated no association between participation in a multimodal exercise

intervention including heavy-load resistance exercise during taxane-based chemotherapy and BCRL

development. While no conclusions regarding the safety of heavy-load resistance and BCRL could

Table 14. Changes in upper extremity strength and breast cancer-specific functional and symptom domains

Abbreviations: CI, confidence interval; Bold = statistical difference (p <0.05); *No upper extremity strength

measures on one participant (LOW) at baseline due to visible and untreated swelling. No upper extremity strength

assessment at subsequent data collections as the participant was receiving treatment for lymphedema. Three

participants (2 HIGH, 1 LOW) were not assessed for upper extremity strength at 6, 12 and 39 weeks, as a

precautionary measure due to swelling or because participants refused. An additional participant (HIGH) received

treatment for lymphedema at 12 and 39 weeks and was therefore not tested; **Higher functional scores (body

image) indicate higher levels of functioning, lower symptom scores (systemic therapy, arm and breast symptoms)

indicate a reduction in symptoms; ǂ Perceived treatment burden; a, b, c Subjective significance of changes from

baseline in terms of a “small”, b “moderate”, c “large” (Osoba, 1998)

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51

be drawn from the conclusions of Study 1, it provided a platform for Studies 2 and 3 to

prospectively evaluate the lymphatic response to heavy-load resistance exercise both acutely after a

single bout of resistance exercise, and after repeated exposure over twelve weeks. In accordance

with the hypothesis, Study 2 found that acute changes in extracellular fluid, arm volume and

symptoms associated with BCRL were similar irrespective of whether low- or heavy-load upper

extremity resistance exercise was performed at all time points with the exception of extracellular

fluid at 72-hours post-exercise, with lower CI’s indicating reductions in swelling after heavy loads.

Further, though individual fluctuations beyond the predetermined thresholds were observed for

BCRL symptoms, the majority of deviations (82%) indicated reductions in severity after resistance

exercise with both intensities. Consistent with the results of Study 2, similar L-Dex scores and self-

reported perceptions of heaviness, swelling and tightness post-intervention were found between the

HIGH and LOW group in Study 3. Additionally, though equivalence was not demonstrated in inter-

arm volume % differences or pain, negative deviations indicated reductions of these outcomes,

favoring the HIGH group. Accordingly, per-protocol analysis of HIGH participants with >65%

adherence also supported equivalence to- or reductions beyond the predetermined equivalence

margins for all outcomes post-intervention.

These consistent findings are in agreement with previous research establishing the

safety of resistance exercise in regard to BCRL based on exercise prescription using low- to

moderate loads. The resistance exercise programs of previous work utilized loads corresponding to

60-80% 1 RM at 8-12 repetitions (59, 85) or started with little or no weight and slowly progressed

with the smallest weight increment possible until loads lifted corresponded to weights that

successfully could be lifted a minimum of 15 repetitions (86) or within a range of 10-12 repetitions

(87). Further our findings are in agreement with the results of two studies by Cormie et al. (13, 73),

demonstrating the safety of heavy-load resistance exercise in women with clinically stable BCRL

who had been diagnosed with breast cancer at least a year before study inclusion. These studies

found that the extent of arm swelling and associated BCRL symptoms remained stable immediately

post-, 24- and 72-hours after one bout of resistance exercise (73), and after twelve-weeks of regular

resistance exercise irrespective of low- or heavy-loads (75-85% of 1 RM using 6-10 RM) were

lifted (13). The results from the present thesis indicate that heavy-load resistance exercise,

specifically corresponding to 85-90% 1 RM at 5-8 repetitions, can be undertaken safely. Therefore,

the current evidence base (7, 8, 10, 11) can now be extended to include participation in heavy-load

resistance exercise.

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52

Point prevalence

Post-intervention point prevalence rates were obtained in Studies 1 and 3 with variations depending

on the method of measurement (Tables 6 and 11). This is in accordance with previous studies

finding that applied diagnostic methods influences incidence and prevalence rates (4, 88) and

exemplifies the challenges in providing accurate estimates of BCRL. Importantly however, similar

point prevalence rates were observed between the HIGH and LOW group in Study 3 for any given

measurement method. Beyond measurement methods, other factors influence estimates of BCRL

prevalence including treatment burden (30) and timing of measurements post-surgery (4, 40)

limiting comparisons between studies. To the authors knowledge, the only meaningful comparison

is to a randomized controlled trial by Kilbreath et al. (n = 160) (66). This study evaluated eight

weeks of low to moderate load resistance exercise, starting 4-6 post-surgery, and found point

prevalent rates corresponding to 7% and 8% in the exercise group (rates were determined using BIS

and Circumference >2 cm, respectively) (66). While the Kilbreath study provides a relevant

comparison in regard to timing and measurement method, it should however be noted that over 95%

of the participants in Studies 1 and 3 were receiving adjuvant taxane-based chemotherapy. In

comparison about half (52.5%) of the participants in the Kilbreath study were receiving taxane-

based chemotherapy. This is relevant, as generalized edema and ensuing arm swelling is a known

side-effect to taxane-based chemotherapy. As such, our data estimating point prevalence of BCRL

following a multimodal exercise intervention including heavy-load resistance exercise provides

further evidence of the safety of this exercise modality.

Muscular strength

Significant post-intervention (p < 0.05) upper extremity strength increases were observed after six

weeks of participation in Body & Cancer (Study 1), and after twelve weeks in the HIGH

intervention (Study 3) (Tables 5 and 14). Further significant between group differences in strength

were observed with an increase of 13% in the HIGH group, compared to a 3% increase in the LOW

group. This is relevant as upper extremity strength in breast cancer survivors during cancer

treatment (without intervention) has been found to be 12-16% lower compared to healthy women

(89). Further, increases in upper extremity strength in the HIGH group corresponded to an effect

size of 0.55 (95% CI 0.35-0.70), similar to pooled estimates from a systematic review (8).

Specifically, fifteen randomized controlled trials evaluating populations with stable BCRL or at risk

for developing BCRL were included in the systematic review, finding that participation in

resistance exercise significantly increased muscular strength compared to controls with an effect

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53

size 0.57 (95% CI 0.37-0.76). Therefore, the observed effect sizes after participation in the HIGH

intervention are encouraging, especially considering that none of the studies in the systematic

review exclusively included previously physically inactive breast cancer survivors receiving taxane-

based chemotherapy. As such, the present study indicates that participation in a multimodal

intervention incorporating heavy-load resistance exercise during chemotherapy can mitigate

declines in muscle strength.

Though no between group differences were observed for any subscale score of the

EORTC QLQ- B23 it should be highlighted that clinically relevant within group reductions in

breast and arm symptoms were found in the HIGH group (90) at both 6- and 12 weeks. These data

are similar to findings by the aforementioned studies of Kilbreath (66) and Cormie (13). Namely,

that clinically relevant reductions were observed post-intervention in both studies, despite no

statistically significant difference between exercise and control groups. Therefore, the data from the

present thesis provide additional evidence that participation in heavy-load resistance does not

precipitate BCRL, and likely alleviates breast and arm symptoms associated with breast cancer

surgery and treatment.

Methodological considerations

Internal validity

Measurement methods

No objective measures of BCRL were obtained in Study 1 with a self-reported clinician diagnosis

defined as a lymphedema case. Circumference measurements, taken at the time of diagnosis, were

however obtained for 38 (93%) of the women that reported a diagnosis of BCRL confirming BCRL

objectively. This measurement method is considered acceptable as a minimum standard provided

that measurements are obtained using a non-stretch tape measure at multiple points on each arm,

and is performed by health professionals with extensive training in this measurement method, in

order to provide reliable measures (39). As the circumference data in Study 1 were collected by

eight different clinicians using varying measurement protocols, circumference measurements

provided are not standardized and the level of training of the various clinicians is unknown.

Therefore, though the attainment of circumference measures adds strength to the study these

limitations should be taken into consideration. Nonetheless, these data reflect the reality of clinical

practice and provided a basis for Studies 2 and 3 where validated objective measurement methods

were used to assess presence and severity of lymphedema.

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Measurement methods such as circumference, water displacement, and perometry are

limited in their ability to differentiate between tissue types and indirectly measure extracellular fluid

(approximately 25% of the total limb), by measuring the total volume of the entire extremity (67,

88). In contrast, BIS directly measures lymph fluid change by measuring the impedance to a low

level electrical current. This allows for a sensitive (74, 91) and reliable measurement method for

detecting subclinical BCRL (91) (early BCRL characterized by an increase in extracellular fluid).

Further, as impedance values are converted to an L-Dex score, inherent volume differences

associated with hand dominance are taken into account (88, 91). However, as lymphedema

progresses BIS loses its sensitivity as extracellular fluid is replaced with fibrotic and adipose

tissues, and is therefore not considered an appropriate measurement method to monitor BCRL over

time (74, 88). However, as the purpose of Studies 2 and 3 were to detect changes in extracellular

fluid in women at risk for BCRL, the BIS measurements add strength to the results.

DXA provides a sensitive measure of tissue composition using a three-compartment

model providing estimates of bone mass composition, fat mass and lean mass where the lean mass

component includes extracellular fluid (71, 74, 75). DXA is sensitive to changes in tissue

composition, and is therefore able to monitor BCRL over time as fluid components are replaced

with adipose tissue. Further, DXA allows for analysis of separate regions of the arm, of potential

clinical importance for patients where swelling is confined to a specific region of the arm or hand

(71, 74, 75, 92). Two different DXA scan and analysis protocols were used in this thesis. In study 2,

separate arm scans were performed and software with a high resolution was used as described by

Gjorup et al., (71), allowing for more precise definition of the region of interest and correct

definition of bone and soft tissue. In study 3, whole body scans were performed and analyzed with

standard total body software (74, 75). However, due to body dimensions exceeding the scan area,

28% of the sample (n = 42) are missing inter-arm volume data, why caution should be applied when

generalizing Study 3 findings to obese women, and is a limitation to this protocol. As an alternative

for these individuals, the potential of performing separate arms scans exists.

In line with existing recommendations advocating for subjective symptom assessment

alongside objective measurements (39), breast and arm symptoms were monitored using a validated

questionnaire (EORTC QLQ-BR23) in Study 3, as well as the severity of swelling, heaviness, pain

and tightness using a numeric rating scale (72, 73) in Study 2 and 3. This is relevant as breast

cancer survivors at risk for lymphedema may experience a variety of symptoms, which can be the

earliest indicator of an ensuing BCRL (93). Further, assessment of symptoms provides a more

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comprehensive evaluation of BCRL that takes the participant’s perceptions into consideration,

which arguably is more important than any objective measurement. Finally, as complete BIS and

DXA data were not available in Study 3, the self-report measures ensured that 100% data for at

least one outcome was available adding strength to the findings.

Blinding

Inherent to exercise intervention studies, Studies 2 and 3 were not double-blinded. However,

considerable effort was made to reduce the potential of assessor bias as data was collected blinded

by medical technicians and study assessors with no knowledge of group allocation. Further,

outcomes were obtained objectively and assessors followed detailed protocols, with previous test

results concealed at follow-up assessments so that neither the participant nor the assessor knew their

previous scores. Keying of data and statistical analyses were also performed blinded to group

allocation.

Equivalence margins

As it was hypothesized that lymphatic response would be similar between groups in Study 2 and 3,

the equivalence design was considered the most appropriate analysis of BCRL outcomes. This was

formalized by defining equivalence margins for each outcome, which ideally represent the

maximum clinically acceptable difference that one is willing to accept in return for the secondary

benefits of a new therapy (heavy-load resistance exercise) (81). The value and impact of

establishing equivalence depends on how well the equivalence margin can be justified in terms of

relevant evidence and clinical judgement, where a narrower equivalence margin makes it more

difficult to establish equivalence (81). This is exemplified by equivalence margins for L-Dex being

set at ± 3.0 in Study 2 rendering conclusions of nonequivalence between heavy- and low-loads at 72

hours. A priori, this threshold was chosen based on change scores considered to be clinically

relevant for persons with BCRL, as no known normative change scores existed for persons without

BCRL. However, in the interim to Study 3, normative L-Dex data were published indicating that L-

Dex scores fluctuate between 9-11 units, (70) which is why equivalence margins were set at ±5.0.

As such, equivalence would have been declared at all time points in Study 2 and illustrates the

challenges in defining meaningful margins in equivalence trials. The chosen equivalence margins in

Studies 2 and 3 were purposely set as more conservative (narrower) in order to ensure credibility.

Arguably though, this may have created confidence limits with an unnecessarily narrow interval

rendering conclusions of nonequivalence. While this may not be the case due to over-conservative

equivalence margins, the negative deviations favoring the Heavy-load or HIGH group add

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confidence to the overall conclusion, that heavy-load resistance exercise does not exacerbate the

development of BCRL acutely or after twelve weeks of repeated exposure.

Follow-up data

39 weeks follow-up data were collected in Study 3, with findings indicating that the longer term

effect of the LOW and HIGH intervention was similar between groups or indicated reductions

favouring the HIGH group. These findings were consistent with the per-protocol analysis, with the

exception of L-Dex and pain as upper CIs indicated a slight increase beyond the predetermined

equivalence margin. However, in general, care should be taken when interpreting the 39 week

follow-up results as no data regarding upper extremity resistance exercise behaviour was collected

post-intervention. Consequently, we cannot determine whether effects seen at 39 weeks were a

result of resistance exercise or other unknown factors and is an additional limitation of this study.

External validity

When generalizing the results of the thesis to the larger breast cancer population at risk for

lymphedema a number of issues should be considered.

In Study 2, five women were excluded at baseline screening if they presented with evidence of

BCRL according to standardized protocols for BIS (L-Dex > 10) or visual inspection (CTC v3.0).

These women could however have been experiencing transient swelling. Further, though

participants were not screened for BCRL and excluded before participation in Studies 1 and 3,

transient cases were not specifically addressed. As such, the findings of this thesis do not extend to

breast cancer survivors displaying increased levels of extracellular fluid, but who have not been

diagnosed with- or received treatment for BCRL. Clinically, this is important as uncertainty exists

as to whether these women would respond in a positive or negative way to heavy-load resistance

exercise. Indeed, though previous studies have found resistance exercise, including heavy-load, to

be both safe and beneficial for breast cancer survivors with lymphedema, these studies have

included women presenting with a clinical diagnosis of BCRL (94) or specifically diagnosed stable

BCRL (e.g. no treatment within the last three months)(7, 8, 95, 96). Therefore, a paucity in

knowledge remains as to the appropriate resistance exercise prescription for women presenting with

potentially transient, unstable lymphedema.

Another limitation to this thesis was that participants making up our sample were on

average younger than women diagnosed with breast cancer. Further, inherent to exercise studies,

there may also have been a selection bias towards women motivated to exercise. Nonetheless, 60%

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of the total cohort (n =194 (n = 41 Study 1, n =153 Study 3)) reported that they were physically

inactive pre- diagnosis which extends generalizability to this vulnerable groups. This is relevant as

fear of lymphedema has been identified as a barrier for physical activity, and especially vigorous or

strength activities (2), which in turn may lead to avoidance and non-adoption of regular physical

activity further increasing risk of BCRL (4). Also, recent work has found that attitude towards

exercise can be transformed from having no priority to being highly prioritized if support to adopt

exercise is received in physically inactive breast cancer survivors during adjuvant chemotherapy

(97). While it is not known whether this translates to long-term behavioral change, the potential for

long term adoption of exercise exists, ultimately leading to better health outcomes (98, 99).

Further, 96% (311) of the participants involved with Study 1, 2 or 3 were receiving

taxane-based adjuvant chemotherapy. As such, findings from this body of work are highly

generalizable to the majority of breast cancer survivors receiving adjuvant chemotherapy as taxane-

based chemotherapy is considered standard first line treatment (16, 100). Further, when considering

other evidence-based risk factors for developing BCRL, participants had an average BMI of 25, 172

(53%) had ALND, and 138 (43%) had undergone a mastectomy. Therefore, as multiple risk factors

for developing BCRL are well represented, applicability extends to breast cancer survivors at

additional risk for developing lymphedema.

Conclusion and clinical implications

In conclusion, across studies, we found no evidence to suggest that participating in heavy-load

resistance exercise during adjuvant taxane-based chemotherapy for breast cancer increased the risk

of developing BCRL. Further, benefits were observed in upper extremity strength, as well as

clinically relevant reductions in breast cancer-specific arm and breast symptoms related to

participation in a multimodal exercise intervention including heavy-load resistance exercise.

Importantly, as this thesis targeted breast cancer survivors with multiple risk factors for developing

BCRL (axillary surgery, physically inactive, taxane-based chemotherapy), applicability extends to

those considered at high-risk for developing BCRL. Therefore, breast cancer survivors should be

encouraged to adopt exercise including heavy-load resistance exercise without fear of exacerbating

BCRL development during adjuvant chemotherapy and beyond.

Breast cancer survivors commonly receive risk reduction advice cautioning against

heavy lifting (2, 46) despite revisions from the National Lymphedema Network, omitting this

particular risk reduction strategy (9). Findings from the present thesis lend clinical evidence that

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supports these revisions, as we found no evidence indicating that intermittent activities of daily

living including heavy-load lifting need be avoided. These results are in accordance with previous

research finding that unrestricted activity of the upper extremities did not alter BCRL risk (86).

Further, Round et al. found that the best functional outcomes were found in those who followed

minimal activity restrictions and used their at-risk extremity as much as the contralateral extremity

(101). As such, breast cancer survivors should be encouraged, without restrictions, to participate in

activities of daily living in accordance with signs and symptoms of BCRL.

Perspectives and future research

The findings from this thesis are in support of current lymphedema risk reduction recommendations

from The National Comprehensive Cancer Network and The American Society of Breast Surgeons (39).

These recommendations advocate for patient education which encourages participation in regular exercise

(without restrictions) and weight management, while also providing information about early signs and

symptoms of BCRL (e.g. tightness, heaviness and swelling) and individual lifetime risk for developing

BCRL. This is relevant as early self-detection combined with prompt intervention has been associated with

better outcomes (102). Indeed, a paradigm shift in BCRL surveillance has occurred with increasing support

for early-detection strategies whereby reversible stages of lymphedema (stage 0 -1) are identified.

Identifying subclinical lymphedema facilitates early, less time consuming and less cumbersome intervention

(e.g. compression garment, self-care, self-MLD) which likely reduces BCRL progression and is likely more

cost-effective than waiting for obvious swelling to occur (22, 103). Various prospective surveillance models

have been proposed to facilitate early detection. However, consensus is lacking with regard to the optimal

frequency and duration of surveillance, and with respect to who should be regularly surveyed (102). Further,

the detection of subclinical lymphedema has in large part been made possible due to the increased sensitivity

of measurement methods such as BIS and perometry, as well as tissue dielectric constant and DXA.

However, agreement as to the optimal measurement method or methods is lacking as advantages and

disadvantages exist for each of these diagnostic tools (102).Therefore, though current data supports the

implementation of prospective surveillance (102), future work should provide prospective comparisons of

measurement methods and current prospective models with long-term follow-up and cost-benefit analyses in

order to elucidate the best early detection strategy (or strategies).

A considerable rationale exists for participating in resistance exercise during adjuvant

chemotherapy as previous clinical trials using low to moderate loads have found that resistance

exercise elicits gains in muscle strength while mitigating adverse changes in physical components

of quality of life, including fatigue, without increased risk of BCRL (7, 8, 10, 11, 54). Moreover, it

has been hypothesized that resistance exercise reduces taxane-related edema through the effects of

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the muscle pump (33, 40). Due to the dose-response relationship that exists between loads lifted and

gains in muscular structure and function it is feasible that additional benefits can be gained. Further

it is plausible that participation in heavy-load resistance exercise may instigate more effective

lymphatic function change than low-load resistance exercise, and in doing so, potentially have a

greater effect on reducing BCRL risk. Therefore, a head to head comparison between resistance

exercise loads should be undertaken with results from this thesis providing the necessary evidence

to carry out this work.

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54. Schmidt ME, Wiskemann J, Armbrust P, Schneeweiss A, Ulrich CM, Steindorf K. Effects of resistance exercise on fatigue and quality of life in breast cancer patients undergoing adjuvant chemotherapy: A randomized controlled trial. Int J Cancer. 2015;137(2):471-80. 55. Demark-Wahnefried W, Campbell KL, Hayes SC. Weight management and its role in breast cancer rehabilitation. Cancer. 2012;118(8 Suppl):2277-87. 56. Harrison S, Hayes SC, Newman B. Level of physical activity and characteristics associated with change following breast cancer diagnosis and treatment. Psychooncology. 2009;18(4):387-94. 57. Irwin ML, Crumley D, McTiernan A, Bernstein L, Baumgartner R, Gilliland FD, Kriska A, Ballard-Barbash R. Physical activity levels before and after a diagnosis of breast carcinoma: the Health, Eating, Activity, and Lifestyle (HEAL) study. Cancer. 2003;97(7):1746-57. 58. Stenholm S, Harris TB, Rantanen T, Visser M, Kritchevsky SB, Ferrucci L. Sarcopenic obesity: definition, cause and consequences. Curr Opin Clin Nutr Metab Care. 2008;11(6):693-700. 59. Courneya KS, Segal RJ, Mackey JR, Gelmon K, Reid RD, Friedenreich CM, Ladha AB, Proulx C, Vallance JK, Lane K, Yasui Y, McKenzie DC. Effects of aerobic and resistance exercise in breast cancer patients receiving adjuvant chemotherapy: a multicenter randomized controlled trial. J Clin Oncol. 2007;25(28):4396-404. 60. Swaroop MN, Ferguson CM, Horick NK, Skolny MN, Miller CL, Jammallo LS, Brunelle CL, O'Toole JA, Isakoff SJ, Specht MC, Taghian AG. Impact of adjuvant taxane-based chemotherapy on development of breast cancer-related lymphedema: results from a large prospective cohort. Breast Cancer Res Treat. 2015;151(2):393-403. 61. Adamsen L, Quist M, Andersen C, Moller T, Herrstedt J, Kronborg D, Baadsgaard MT, Vistisen K, Midtgaard J, Christiansen B, Stage M, Kronborg MT, Rorth M. Effect of a multimodal high intensity exercise intervention in cancer patients undergoing chemotherapy: randomised controlled trial. BMJ. 2009;339:b3410. 62. Altman DG. Practical Statistics for Medical Research. London: Chapman & Hall/CRC; 1991. 624 p. 63. Danish Health and Medical Authority. Physical activity: recommendations for adults (18-64 years old) 2013 [cited 2017 Nov]. Available from: http://www.sst.dk/English/Health_promotion/Physical_activity/Recommendations_for_adults.aspx. 64. Moller T, Lillelund C, Andersen C, Ejlertsen B, Norgaard L, Christensen KB, Vadstrup E, Diderichsen F, Hendriksen C, Bloomquist K, Adamsen L. At cancer diagnosis: a 'window of opportunity' for behavioural change towards physical activity. A randomised feasibility study in patients with colon and breast cancer. BMJ Open. 2013;3(11):e003556. 65. Saltin B, Grimby G. Physiological analysis of middle-aged and old former athletes. Comparison with still active athletes of the same ages. Circulation. 1968;38(6):1104-15. 66. Kilbreath SL, Refshauge KM, Beith JM, Ward LC, Lee M, Simpson JM, Hansen R. Upper limb progressive resistance training and stretching exercises following surgery for early breast cancer: a randomized controlled trial. Breast Cancer Res Treat. 2012;133(2):667-76. 67. Cornish BH, Thomas BJ, Ward LC, Hirst C, Bunce IH. A new technique for the quantification of peripheral edema with application in both unilateral and bilateral cases. Angiology. 2002;53(1):41-7. 68. Ward LC, Dylke E, Czerniec S, Isenring E, Kilbreath SL. Confirmation of the reference impedance ratios used for assessment of breast cancer-related lymphedema by bioelectrical impedance spectroscopy. Lymphat Res Biol. 2011;9(1):47-51. 69. Cornish BH, Jacobs A, Thomas BJ, Ward LC. Optimizing electrode sites for segmental bioimpedance measurements. Physiol Meas. 1999;20(3):241-50. 70. Hayes S, Janda M, Steele M, et al. Identifying diagnostic criteria for upper- and lower-limb lymphoedema Impedimed Limited: Queensland University of Technology Faculty of Health, School of Public Health and Social Work and Institute of Health and Biomedical Innovation; 2016 [updated 3 July 2017; cited 2017 July 3]. 17]. Available from: https://eprints.qut.edu.au/view/person/Hayes,_Sandra.html#group_report.

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71. Gjorup C, Zerahn B, Hendel HW. Assessment of volume measurement of breast cancer-related lymphedema by three methods: circumference measurement, water displacement, and dual energy X-ray absorptiometry. Lymphat Res Biol. 2010;8(2):111-9. 72. Hawker GA, Mian S, Kendzerska T, French M. Measures of adult pain: Visual Analog Scale for Pain (VAS Pain), Numeric Rating Scale for Pain (NRS Pain), McGill Pain Questionnaire (MPQ), Short-Form McGill Pain Questionnaire (SF-MPQ), Chronic Pain Grade Scale (CPGS), Short Form-36 Bodily Pain Scale (SF-36 BPS), and Measure of Intermittent and Constant Osteoarthritis Pain (ICOAP). Arthritis Care Res (Hoboken). 2011;63 Suppl 11:S240-52. 73. Cormie P, Galvao DA, Spry N, Newton RU. Neither heavy nor light load resistance exercise acutely exacerbates lymphedema in breast cancer survivors. Integr Cancer Ther. 2013;12(5):423-32. 74. Newman AL, Rosenthall L, Towers A, Hodgson P, Shay CA, Tidhar D, Vigano A, Kilgour RD. Determining the precision of dual energy x-ray absorptiometry and bioelectric impedance spectroscopy in the assessment of breast cancer-related lymphedema. Lymphat Res Biol. 2013;11(2):104-9. 75. Brorson H, Ohlin K, Olsson G, Karlsson MK. Breast cancer-related chronic arm lymphedema is associated with excess adipose and muscle tissue. Lymphat Res Biol. 2009;7(1):3-10. 76. Sprangers MA, Groenvold M, Arraras JI, Franklin J, te Velde A, Muller M, Franzini L, Williams A, de Haes HC, Hopwood P, Cull A, Aaronson NK. The European Organization for Research and Treatment of Cancer breast cancer-specific quality-of-life questionnaire module: first results from a three-country field study. J Clin Oncol. 1996;14(10):2756-68. 77. Nguyen J, Popovic M, Chow E, Cella D, Beaumont JL, Chu D, DiGiovanni J, Lam H, Pulenzas N, Bottomley A. EORTC QLQ-BR23 and FACT-B for the assessment of quality of life in patients with breast cancer: a literature review. J Comp Eff Res. 2015;4(2):157-66. 78. Liang K-Y, & Zeger, S.L. Longitudinal data analysis using generalized linear models. Biometrika. 1986;73:13-22. 79. Stout Gergich NL, Pfalzer LA, McGarvey C, Springer B, Gerber LH, Soballe P. Preoperative assessment enables the early diagnosis and successful treatment of lymphedema. Cancer. 2008;112(12):2809-19. 80. Westlake WJ. Use of confidence intervals in analysis of comparative bioavailability trials. J Pharm Sci. 1972;61(8):1340-1. 81. Walker E, Nowacki AS. Understanding equivalence and noninferiority testing. J Gen Intern Med. 2011;26(2):192-6. 82. Team RC. R: A language and environment for statistical computing.: R Foundation for Statistical Computing; 2015 [Available from: https://www.R-project.org/. 83. Halekoh U HS, Yan J. The R package geepack for generalized estimatin equations. J Stat Softw. 2006;15(2):1-11. 84. Cohen J. Statistical power analysis for the behavioral sciences. Second ed: Academic press; 1977. 85. Simonavice E, Kim JS, Panton L. Effects of resistance exercise in women with or at risk for breast cancer-related lymphedema. Support Care Cancer. 2017;25(1):9-15. 86. Sagen A, Karesen R, Risberg MA. Physical activity for the affected limb and arm lymphedema after breast cancer surgery. A prospective, randomized controlled trial with two years follow-up. Acta Oncol. 2009;48(8):1102-10. 87. Schmitz KH, Ahmed RL, Troxel AB, Cheville A, Lewis-Grant L, Smith R, Bryan CJ, Williams-Smith CT, Chittams J. Weight lifting for women at risk for breast cancer-related lymphedema: a randomized trial. JAMA. 2010;304(24):2699-705. 88. Hayes SC, Speck RM, Reimet E, Stark A, Schmitz KH. Does the effect of weight lifting on lymphedema following breast cancer differ by diagnostic method: results from a randomized controlled trial. Breast Cancer Res Treat. 2011;130(1):227-34.

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89. Klassen O, Schmidt ME, Ulrich CM, Schneeweiss A, Potthoff K, Steindorf K, Wiskemann J. Muscle strength in breast cancer patients receiving different treatment regimes. J Cachexia Sarcopenia Muscle. 2017;8(2):305-16. 90. Osoba D, Rodrigues G, Myles J, Zee B, Pater J. Interpreting the significance of changes in health-related quality-of-life scores. J Clin Oncol. 1998;16(1):139-44. 91. Fu MR, Cleland CM, Guth AA, Kayal M, Haber J, Cartwright F, Kleinman R, Kang Y, Scagliola J, Axelrod D. L-dex ratio in detecting breast cancer-related lymphedema: reliability, sensitivity, and specificity. Lymphology. 2013;46(2):85-96. 92. Czerniec SA, Ward LC, Meerkin JD, Kilbreath SL. Assessment of segmental arm soft tissue composition in breast cancer-related lymphedema: a pilot study using dual energy X-ray absorptiometry and bioimpedance spectroscopy. Lymphat Res Biol. 2015;13(1):33-9. 93. Fu MR, Axelrod D, Cleland CM, Qiu Z, Guth AA, Kleinman R, Scagliola J, Haber J. Symptom report in detecting breast cancer-related lymphedema. Breast Cancer (Dove Med Press). 2015;7:345-52. 94. Hayes SC, Reul-Hirche H, Turner J. Exercise and secondary lymphedema: safety, potential benefits, and research issues. Med Sci Sports Exerc. 2009;41(3):483-9. 95. Schmitz KH, Ahmed RL, Troxel A, Cheville A, Smith R, Lewis-Grant L, Bryan CJ, Williams-Smith CT, Greene QP. Weight lifting in women with breast-cancer-related lymphedema. N Engl J Med. 2009;361(7):664-73. 96. Buchan J, Janda M, Box R, Schmitz K, Hayes S. A Randomized Trial on the Effect of Exercise Mode on Breast Cancer-Related Lymphedema. Med Sci Sports Exerc. 2016;48(10):1866-74. 97. Adamsen L, Andersen C, Lillelund C, Bloomquist K, Moller T. Rethinking exercise identity: a qualitative study of physically inactive cancer patients' transforming process while undergoing chemotherapy. BMJ Open. 2017;7(8):e016689. 98. Holmes MD, Chen WY, Feskanich D, Kroenke CH, Colditz GA. Physical activity and survival after breast cancer diagnosis. JAMA. 2005;293(20):2479-86. 99. Fong DY, Ho JW, Hui BP, Lee AM, Macfarlane DJ, Leung SS, Cerin E, Chan WY, Leung IP, Lam SH, Taylor AJ, Cheng KK. Physical activity for cancer survivors: meta-analysis of randomised controlled trials. BMJ. 2012;344:e70. 100. Giordano SH, Lin YL, Kuo YF, Hortobagyi GN, Goodwin JS. Decline in the use of anthracyclines for breast cancer. J Clin Oncol. 2012;30(18):2232-9. 101. Round T, Hayes SC, Newman B. How do recovery advice and behavioural characteristics influence upper-body function and quality of life among women 6 months after breast cancer diagnosis? Support Care Cancer. 2006;14(1):22-9. 102. Shah C, Arthur DW, Wazer D, Khan A, Ridner S, Vicini F. The impact of early detection and intervention of breast cancer-related lymphedema: a systematic review. Cancer Med. 2016;5(6):1154-62. 103. Stout NL, Pfalzer LA, Springer B, Levy E, McGarvey CL, Danoff JV, Gerber LH, Soballe PW. Breast cancer-related lymphedema: comparing direct costs of a prospective surveillance model and a traditional model of care. Phys Ther. 2012;92(1):152-63.

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Appendices

Appendix A: Papers I to IV

Appendix B: Co-authorship declarations

Appendix C: Study 1

Telephone interview guide

Appendix D: Study 3

EORTC- BR23

BCRL information

Subjective BCRL outcomes structured interview

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Appendix A: Papers I to IV

 

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Paper I

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Correspondence: K. Bloomquist, University Hospitals Centre for Health Research, Copenhagen University Hospital, 2100 Copenhagen, Denmark. Tel: � 45 35457336. Fax: � 45 35457399. E-mail: [email protected]

(Received 14 June 2013 ; accepted 26 August 2013 )

ORIGINAL ARTICLE

Heavy resistance training and lymphedema: Prevalence of breast cancer-related lymphedema in participants of an exercise intervention utilizing heavy load resistance training

KIRA BLOOMQUIST 1 , TONNY KARLSMARK 2 , KARL BANG CHRISTENSEN 3 & LIS ADAMSEN 1,4

1 University Hospitals Centre for Health Research, Copenhagen University Hospital, Copenhagen, Denmark, 2 Department of Dermatology and Venerology, Bispebjerg Hospital, University Hospital of Copenhagen, Denmark, 3 Department of Public Health, Section of Biostatistics, University of Copenhagen, Denmark and 4 Department of Public Health, University of Copenhagen, Denmark

Abstract Background. There is limited knowledge regarding progressive resistance training during adjuvant chemotherapy and the risk of developing breast cancer-related lymphedema (BCRL). Furthermore, no studies have investigated the safety of resistance training with heavy loads ( � 80% 1 repetition maximum) in this population. ‘ Body and Cancer ’ is a six-week, nine-hour weekly, supervised, multimodal exercise intervention utilizing progressive resistance training with heavy loads for cancer patients undergoing chemotherapy. The purpose of the present study was to estimate the prevalence of BCRL in former participants, and identify associations between progressive resistance training with heavy loads, and the development of BCRL. Material and methods. This was a descriptive study. Population: Women treated for breast cancer (n � 149), who had participated in the ‘ Body and Cancer ’ exercise intervention between 1 January 2010 and 31 December 2011 participated in a structured telephone interview. The average follow-up time was 14 months (range 4 – 26). A clinical diagnosis of BCRL reported by the participant was the primary outcome. Results. A total of 27.5% reported that they had been diagnosed with BCRL by a clinician. This was true for 44.4% with axillary node dissection. No statistically signifi cant association between strength gains during the exercise intervention, and the development of BCRL was observed, nor was self-reported participation in progressive resistance training with heavy loads up to three months post-intervention. Conclusion. The prevalence of BCRL among former “ Body and Cancer ” participants at follow-up was 27.5%. There appears to be no association between performing heavy resistance training during adjuvant treatment (chemotherapy/radiotherapy), and the development of BCRL. However randomized controlled trials should be performed to confi rm this observation.

Breast cancer-related lymphedema (BCRL) as a result of acquired interruption or damage to the axil-lary lymphatic system is associated with signifi cant physical, functional, and psychosocial burden [1].The incidence and prevalence of BCRL have been diffi cult to quantify due to a lack of a standardized measurement method and a uniform defi nition of what constitutes BCRL, as well as the lack of an evidence-based defi nition of transient versus chronic lymphedema [1 – 3]. Moreover, prevalence rates have been found to vary based on the surgery performed and the extent of adjuvant treatment ranging from 13% to 65% [4]. In a meta-analysis from 2013, Disipio et al. found a pooled estimate for incidence

of 16.6% based on 72 studies [1]. However, inci-dence rates varied depending on study design rang-ing from 8.4% in retrospective cohort studies to 21.4% in prospective cohort studies, as well as a result of diagnostic method ranging from 5.0% with lymphoscintigraphy to 28.2% when multiple mea-surement methods were applied. The incidence of BCRL seemed to increase with time up to two years from diagnosis or surgery (12 – � 24 months, 18.9%), after which a decrease in incidence was observed. Lastly, the incidence of BCRL was four times higher among women who had AND (19.9%) than in women who had sentinel node biopsy (SNB) (5.6%).

Acta Oncologica, 2014; 53: 216–225

ISSN 0284-186X print/ISSN 1651-226X online © 2014 Informa HealthcareDOI: 10.3109/0284186X.2013.844356

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Heavy resistance training and lymphedema 217

There has been a longstanding concern that pro-gressive resistance training (PRT) increased the risk of developing BCRL [5]. However, a growing body of evidence indicates that PRT does not increase BCRL risk [5,6]. Furthermore, it is well demon-strated in the literature that PRT has a benefi cial effect on a number of the side- or late effects related to breast cancer treatment by positively impacting self-perceptions of body image [7], increasing vital-ity [8], lean body mass [9,10], bone mineral density [11], and muscular strength [9,10,12]. Indeed, 2010 guidelines from the American College of Sports Medicine (ACSM) [6] advocate PRT. How-ever, none of the seven studies that these guidelines are based on were conducted on patients undergo-ing adjuvant treatment (chemotherapy and/or radio-therapy). Furthermore, the heaviest loads lifted corresponded to three sets of 10 repetitions [12,13], considered moderate resistance [14]. Since the ACSM guidelines were published, four randomized controlled exercise trials utilizing PRT during adju-vant treatment have been performed [9,15 – 17]. Only one of these had BCRL as the primary out-come. Furthermore, maximum loads of 60 – 70% of 1 RM (moderate load) were the heaviest loads lifted. Recently, Cormie et al. conducted two studies which examined the safety of heavy resistance training in women with BCRL. The studies found that resis-tance training with heavy loads ( � 80% 1 RM) did not acutely exacerbate an existing lymphedema [18], and was found to be a safe training mode, associated with improvements in physical function and quality of life [19]. However, as these studies were performed in women with BCRL, a gap in knowledge exists concerning the safety of heavy load PRT in regard to BCRL risk. Therefore studies are needed that investigate the safety of PRT during adjuvant treatment with BCRL as the primary out-come, as well as PRT with heavier loads.

Originally a RCT (for details see Adamsen et al. [20]) ‘ Body and Cancer ’ (B & C) has been offered as an exercise intervention for cancer patients undergo-ing chemotherapy in the Copenhagen area since 2007. To date approximately 1300 participants rep-resenting over 21 diagnoses have participated in this six-week, nine-hour weekly, supervised multi-modal exercise intervention. Among the unique characteristics of this intervention is the utilization of low intensity components (relaxation- and body awareness training and massage) with high intensity components (aerobic- and resistance training).

Of interest for the present study are the high intensity days (Monday, Wednesday, Friday) where participants engage in a cardiovascular warm-up (esti-mated average intensity of 9 METs, 4.5 MET hours per training session), followed by PRT (estimated

average intensity of 5.5 METs, 4 MET hours per training session) and 15 – 30 minutes of interval train-ing on stationary bicycles with peak loads of 85 – 95% of each participants maximum heart rate (estimated average intensity of 15 METs, 3.75 MET hours per training session. Lastly, participants engage in relax-ation training lasting approximately 15 minutes.

Six machines are used during PRT: leg press, chest press, latissimus (lat.) pull down, abdominal crunch, lower back and knee extension (Technogym ® , Gambettola, Italy). Muscular strength is ascertained in all six resistance training machines at baseline and at the commencement of the intervention using the 1RM test [20]. Partici-pants are encouraged to lift loads corresponding to 2 – 3 sets of 8 – 12 repetitions at 70% 1RM the fi rst week, progressing to 80% 1RM the second week. From week three loads are lifted corresponding to three sets of 5 – 8 repetitions at 80 – 90% 1 RM. Par-ticipants who develop subjective (e.g. sensations of heaviness or swelling) or objective (e.g. visible swell-ing, pitting edema) signs of BCRL or experience exacerbations of an existing BCRL are instructed by the staff (physical therapists and trained nurse spe-cialists) to decrease loads or refrain from the lat. pull down and chest press exercises and are referred to hospital- or private practice lymphedema thera-pists for evaluation and treatment. No systematic registration of BCRL has ever been carried out.

Therefore, using a cross-sectional design, the purpose of the present study was to investigate the prevalence of BCRL in breast cancer patients who participated in B & C from 1 January 2010 to 31 December 2011. It was hypothesized that par-ticipation in this exercise intervention utilizing heavy load PRT ( � 80% 1 RM) was not associated with an increased risk of BCRL.

Material and methods

Recruitment

Breast cancer patients who had participated in the exercise intervention from 1 January 2010 to 31 December 2011 were identifi ed in the B & C database (n � 180). Participants came from four university hospitals in the Copenhagen area and were eligible for the exercise intervention if they had a diagnosis of breast cancer, had received at least one cycle of chemotherapy for advanced disease or as adjuvant treatment, had a WHO performance status of 0 or 1 and otherwise had been approved to participate by the treating oncologist. Medical records were searched for a clinician diagnosis of BCRL, recurrent cancer, and mortality status. Figure 1 details the recruitment and exclusion process, leaving a study sample of 149 women.

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218 K. Bloomquist et al.

Data sources

Electronic medical records . Data regarding surgery and treatment as well as BCRL, recurrent cancer and mortality status were obtained from electronic medical records.

Structured telephone interview. A structured telephone interview was administered by one of the authors (KB) a research physical therapist affi liated with the exercise intervention, and lasted on average 15 minutes. Responses were recorded on a pre-printed form. All telephone interviews were obtained within a six-week period.

The primary outcome, a clinical diagnosis of BCRL, was ascertained by asking the participant if she had been diagnosed with lymphedema. She was defi ned as having BCRL if she answered “ yes ” . If the participant reported having been diagnosed with BCRL she also was asked to report when and by whom the diagnosis was made as well as which region was affected (hand, arm, breast, torso). Demographic, treatment, and training/physical activity characteristics were also obtained. More specifi cally, demographic characteristics included age, current BMI, relationship status, age of children living at home, education and current occupation. Treatment characteristics included whether surgery had been performed on the dominant/non-dominant side and whether they had been introduced to post-operative exercises for breast cancer patients. Furthermore, the interview supplemented any information lacking from the medical records. Behavioral characteristics included whether the par-ticipant had performed post-operative exercises before participating in the intervention, whether they had engaged in PRT 1 – 3 � /week between sur-gery and B & C, and whether they had engaged in

PRT 1 – 3 � /week post-intervention, and if so for how long, and with which loads. In addition, leisure time physical activity was explored using a validated method [21].

Arm circumference measurements. For participants answering “ yes ” to having been diagnosed with BCRL, circumference measurements (measured at the time of lymphedema assessment) were obtained from medical records. If no circumference measure-ments were noted in the medical records, measure-ments were obtained by contacting the clinician (e.g. rheumatologist, general practitioner, lym-phedema therapist, etc.) that had diagnosed the participant. No standardized protocol for measur-ing was used as each clinician had their own proto-col ranging from fi ve to seven measuring points. A participant was considered to have BCRL if an interlimb difference of � 2 cm at to two or more measures was reported [16].

B & C database. Baseline BMI and pre-illness physical activity levels [21] were obtained from the database, as well as baseline and post-intervention muscular strength (1 RM) of the upper (chest press) and lower body (leg press) and adherence to the intervention.

Statistical analysis

Statistical procedures were performed using the Statistical Package for Social Sciences (SPSS) software (version 19) for Windows. Descriptive sta-tistics are presented as proportions for categorical variables and as means and standard error (SE) for continuous variables unless otherwise noted. Mean changes in muscular strength (1 RM) after six weeks of training were assessed using a paired t-test, and were analyzed on a per-protocol (PP) basis, includ-ing only participants with baseline and six-week mea-surements as well as on an intention to treat (ITT) basis using baseline observation carried forward (BOCF). Point prevalence was calculated at the time of the present study [on average 14 months post-intervention (range 4 – 26)], and estimated ret-rospectively at the commencement of B & C and at 1, 2, 3, and 4 months post-B & C participation.

To compare differences between participants that had been diagnosed with BCRL and those that had not χ 2 -test and Fisher ’ s exact test were used to compare categorical variables. Where relevant categorical variables were dichotomized. Continuous variables were compared using two-sample t-tests. Levene ’ s test for equality of variances was performed and results presented use pooled variances unless otherwise noted. A two-tailed p � 0.05 was taken as evidence of statistical signifi cance. From the

Figure 1. Flow chart depicting selection of the study population derived from women treated for breast cancer who had participated in ‘ Body and Cancer ’ from January 2010 through December 2011.

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Heavy resistance training and lymphedema 219

literature it was known that comparison studies were carried out on AND populations alone, and therefore a sub-analysis of participants with AND was performed.

Ethical considerations

The study was performed in accordance with the Helsinki Declaration, and approved by the Danish Data Protective Agency .

Results

Participant characteristics

Of the 158 women contacted, 94.3% (n � 149) were included in the study. The mean age was 47.7 years and 14.9% had children � 7 years of age living at home. Most were in a relationship (71.8%), had higher than a secondary education (86.0%) and were currently employed (73.8%), with over half (63.6%) describing their employment as being “ not physically demanding ” . The mean self-reported BMI was 24.1, with 35.6% classifi ed as overweight ( � 25). 41.6% had undergone breast ablation sur-gery and 60.4% had received AND, with 53.7% having undergone surgery on the non-dominant side. All had undergone chemotherapy, with 94.6% having received adjuvant chemotherapy. The majority of the women had received radiotherapy (80.5%), and 79.9% had received/were receiving endocrine treatment, while 15.4% were receiving/had received trastuzumubab.

B & C participation

On average participants had initiated B & C 16.5 (range 5.6 – 27.6) weeks after surgery, and had undergone 3.8 (range 1 – 8) cycles of chemotherapy. Over half (60.4%) had an adherence rate of at least 70% (17 of 24 training days) to the exercise interven-tion. Both the per-protocol (Table 1) and ITT (not shown) analyses revealed increases in upper and lower body muscular strength after six weeks of

training. Mean time from B & C termination to tele-phone interview participation was 14 months, ranging between 4 and 26 months. In total 17.4% (n � 26) had been fi nished with the intervention up to six months, 31.5% (n � 47) between 7 and 12 months and 38.3% (n � 57) between 13 and 24 months. 12.8% (n � 19) had participated in B & C more than two years previously.

Self-reported leisure time physical activity levels

Over half of the participants (70.9%) reported that they had been physically active at least three hours per week, of which 7.8% had been physically active more than four hours per week pre-illness. At follow-up, on average 14 months post-intervention, a shift was seen towards more physical activity as 78.5% currently reported being physically active at least three hours per week, of which 31.5% cur-rently were physically active more than four hours per week (p � 0.001).

Point prevalence of BCRL

The total prevalence 4 – 26 months post-intervention (mean 14) was 27.5% (Table II). A sub-analysis of the AND population revealed a prevalence of 44.4%. Six percent reported that they had been diagnosed with BCRL during the intervention increasing to 17.4% at four months post-interven-tion. In the AND population 10.0%, and 27.8%, respectively reported a BCRL diagnosis (Table II). All BCRL cases had received AND, with the excep-tion of one participant. Notably, among women with a diagnosis of BCRL one reported swelling in the hand only, three in the breast only, and one in the torso only.

Arm circumference measurements

Arm circumference measurements were taken at the time of lymphedema assessment by various clinicians at eight different facilities (two hospitals, six private

Table I. Strength outcomes after six weeks in ‘ Body and Cancer ’ .

Total Population AND Population

Total Population No BCRL BCRL No BCRL BCRL

Variable nBaseline

Mean (SE)6 weeks

Mean (SE) Δ Mean

Mean (SE) n Δ Mean

(SE) n Δ Mean

(SE) p-value † n Δ Mean

(SE) n Δ Mean

(SE) p-value †

1RM Chest Press (kg) 125 27.2 (0.66) 31.9 (0.70) 4.7 (0.43) ∗ 93 4.6 (0.47) 32 5.0 (0.98) 0.68 41 4.3 (0.69) 31 4.5 (0.88) 0.82

1RM Leg Press (kg) 132 76.0 (2.00) 94.8 (2.45) 18.8 (1.75) ∗ 96 16.5 (1.82) 36 24.7 (4.07) 0.07 45 14.9 (2.48) 35 23.7 (4.06) 0.06

Δ Change between baseline and 6 weeks. ∗ (p-value � 0.05). † No BCRL as reference.

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220 K. Bloomquist et al.

practice lymphedema therapists) with varying proto-cols. Measurements were obtained for 38 of the 41 (92.7%) participants diagnosed with BCRL. Of these, 47.4% had an interlimb difference of � 2 cm at two or more measures. Thus according to this diag-nostic method, and with the criteria applied, preva-lence at the study point was 12.3%, increasing from 3.4% during the intervention, to 10.3% four months post-intervention. In the AND population, point prevalence at the study period was 19.5%, ranging between 5.8% and 16.1%, respectively (Table II).

Variable differences

A larger percentage of participants diagnosed with BCRL had a BMI � 25 (p � 0.023), had undergone AND (p � 0.000) and had received radiotherapy (p � 0.005) (Table III). In contrast fewer had received trastuzumubab (p � 0.040). Over 90% of the par-ticipants diagnosed with BCRL had performed post-surgery exercises focusing on range of motion, at least 3 � /week before initiating the B & C interven-tion, compared to 68% in the no BCRL group. No between group differences were noted in regard to PRT before or after B & C (Table III), nor to strength development after six weeks of training (Table I).

Variable differences in the AND population

Sub-analysis of the AND population revealed that more participants diagnosed with BCRL currently were overweight (p � 0.001), or had been overweight at baseline (p � 0.017) (Table IV). No between group differences were found in regard to post-surgery exercises. However, 83.5% of the AND population had performed these exercises in comparison to 60.3% that had received SNB (p � 0.003), thus the between group difference (No BCRL/BCRL) found in the total population was associated with axillary surgery. Similarly, no between group difference was found in regard to radiotherapy. However, 93.3% in the AND population had received radiotherapy in com-parison to 62.3% in the SNB population (p � 0.000).

In contrast to the total population, no between group difference was found in regard to trastuzu-mubab treatment, however no association to axillary surgery was found. No between group differences were noted in regard to PRT before or after the inter-vention (Table IV), nor to strength development after six weeks of training (Table I).

Discussion

The prevalence of BCRL, 4 – 26 months after participation in B & C, was 27.5%. Sub-analysis revealed a prevalence rate of 44.4% amongst par-ticipants who had undergone AND. More partici-pants in the group diagnosed with BCRL were overweight and had undergone radiotherapy and AND. No associations were found between per-forming heavy resistance training and the develop-ment of BCRL.

Comparison to intervention studies during adjuvant treatment

Total population. The estimated prevalence of women reporting that they had been diagnosed with BCRL during the exercise intervention was 6.0%. These results are similar to Kilbreath et al. [16] that reported a BCRL incidence of 7 – 11% (depending on the measurement method applied) after an eight-week training intervention ultilizing moderate loads. The estimated prevalence had increased to 17.4% four months post-B & C in comparison to 7 – 8% six months post-intervention in Kilbreath ’ s study. However, using the same measurement method and criteria (arm circumference differences � 2 cm at two or more measures) the rate of BCRL was 10.3% in the present study and 7% in the Kilbreath study.

AND population. Among participants with AND, the post-intervention prevalence was 10.0%, increasing to 27.8% four months post-B & C. Comparably, in the Kilbreath study, between 20% and 33% had

Table II. Point prevalence of self-reported diagnosed lymphedema and arm circumference measurements in relation to participation in the intervention. Values are numbers of participants (percentages).

Time in relation to participation in ‘Body and Cancer’

Diagnosed BCRLTotal population

(n � 149)

Circumference � 2Total population

(n � 146) †

Diagnosed BCRLAND population

(n � 90)

Circumference � 2AND population

(n � 87) †

During intervention 9 (6.0) 5 (3.4) 9 (10.0) 5 (5.8)Within 1 month post-intervention 16 (10.7) 10 (6.8) 16 (17.8) 10 (11.5)1 – 2 months post-intervention 21 (14.1) 11 (7.5) 21 (23.3) 10 (11.5)2 – 3 months post-intervention 23 (15.4) 13 (8.9) 23 (25.6) 12 (13.7)3 – 4 months post-intervention 26 (17.4) 15 (10.3) 25 (27.8) 14 (16.1)Total at study ∗ 41 (27.5) 18 (12.3) 40 (44.4) 17 (19.5)

∗ On average 14 months (4 – 26 months) post-intervention. † Circumference measurements not available for 3 participants.

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Heavy resistance training and lymphedema 221

Table III. Characteristics of participants with and without BCRL (n � 149). Values are numbers (percentages) unless stated otherwise.

Demographic characteristicsNo BCRL (n � 108)

BCRL (n � 41) p-value

Age mean (SD) 47.8 (8.7) 47.7 (7.9) 0.939Children in care � 7 years 18 (16.7) 4 (9.8) 0.438Married, cohabitating or in a relationship 79 (73.1) 28 (68.3) 0.548Education � secondary school 90 (83.3) 38 (92.7) 0.190Employed (full/part time) 80 (74.1) 30 (73.2) 1.00Not physically demanding work 50 (46.3) 20 (48.8) 0.936Moderately physically demanding work 25 (23.1) 9 (22.0)Very physically demanding work 5 (4.6) 1 (2.4) Health and medical characteristics Baseline BMI � 25 ∗ 43 (40.2) 20 (50.0) 0.350 Current BMI � 25 33 (31.0) 21 (51.2) 0.023 Breast ablation 44 (40.7) 18 (43.9) 0.871 Axillary node dissection 50 (46.3) 40 (97.6) 0.000 Non-dominant arm 56 (51.9) 24 (58.5) 0.581Chemotherapy3 � CE � 3 � docetaxel 73 (67.6) 29 (70.7) 0.6206 � CT 28 (25.9) 11 (26.8)Other 7 (6.5) 1 (2.4) Received radiotherapy 81 (75.0) 39 (95.1) 0.005 Received endocrine treatment 85 (78.7) 34 (82.9) 0.652 Received trastuzumubab 21 (19.4) 2 (4.9) 0.040 Physical activity level (self-reported) Pre-illness † Sedentary 4 (3.9) 1 (2.8) 0.585 Walking or cycling for pleasure 27 (26.0) 9 (25.0) Regular physical exercise, at least 3 h/week 66 (63.5) 23 (63.9) Intense physical activity � 4 h/week 7 (6.7) 5 (4.6)Present time Sedentary 2 (1.9) 1 (2.4) 0.473 Walking or cycling for pleasure 19 (17.6) 10 (24.4) Regular physical exercise at least 3 h/week 55 (50.9) 15 (36.6) Intense physical activity � 4 h/week 32 (29.6) 15 (36.6) Training Performed exercises prescribed post-surgery ‡ No 32 (31.7) 3 (7.5) 0.010 3 � weekly 16 (15.8) 7 (17.5) Daily 53 (52.5) 30 (75.0)PRT between surgery and ‘ Body and Cancer ’ ‡ 18 (17.8) 10 (25.0) 0.355PRT 3 months after ‘ Body and Cancer ’ 56 (51.9) 23 (56.0) 0.715Utilized 2 – 3 sets of 5 – 8 RM 29 (26.9) 15 (37.5) 0.325Adherence � 70% while in ‘ Body and Cancer ’ 70 (64.8) 20 (48.8) 0.092

∗ (n � 141, (n � 40 BCRL, n � 107 no BCRL)) due to missing data; † [n � 141, (n � 36 BCRL, n � 104 no BCRL)] due to missing data; ‡ [n � 141, (n � 40 BCRL, n � 101 no BCRL)] participants receiving neo-adjuvant; (n � 5) or chemotherapy for advanced disease (n � 3) not included.

developed BCRL post-intervention and 15 – 30% six months post-intervention. Courneya et al. reported an incidence rate of 3.7%, using water displacement, after a median of 17 weeks of PRT during adjuvant chemotherapy [9]. Notably, none of these women had received radiotherapy, and no follow-up mea-sures were reported. In a study by Sagen et al. participants initiated the intervention within the fi rst week of surgery [17]. After three months of strength training with light to moderate loads, 5% had developed BCRL (water displacement). At two years post-surgery the incidence rate was 13%. This stands in contrast to the present study with 44.4%

reporting that they had been diagnosed with BCRL 8 – 28 months post-surgery. However due to inherent differences in study design (RCT/cross-sectional), differing measurement methods and treatment bur-den, caution should be applied when interpreting these diverging results.

RCT versus cross-sectional studies. Inherent differences in study design make it diffi cult to compare results from the controlled framework of a RCT with results from a cross-sectional study. Participants were excluded from the RCTs if they had undergone reconstructive surgery [9], had metastatic cancer

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222 K. Bloomquist et al.

Table IV. Sub-analysis in the AND population (n � 90). Characteristics of participants with and without BCRL. Values are numbers (percentages) unless stated otherwise.

Demographic characteristicsNo BCRL (n � 50)

BCRL (n � 40) p - value

Age mean (SD) 49.2 (9.0) 47.8 (8.0) 0.436Children in care � 7 years 9 (18.0) 4 (10.0) 0.371Married, cohabitating or in a relationship 37 (74.0) 28 (70.0) 0.813Education � secondary school 44 (88.0) 37 (92.5) 0.726Employed (full/part time) 40 (80.0) 29 (72.5) 0.458

Not physically demanding work 27 (54.0) 19 (47.5) 0.832Moderately physically demanding work 11 (22.0) 9 (22.5)Very physically demanding work 2 (4.0) 1 (2.5)

Health and medical characteristics Baseline BMI � 25 ∗ 13 (26.0) 20 (51.3) 0.017 Study BMI � 25 9 (18.0) 21 (52.5) 0.001 Breast ablation 25 (50.0) 18 (45.0) 0.676Non-dominant arm 32 (64.0) 23 (57.5) 0.664Chemotherapy3 � CE � 3 � docetaxel 33 (66.0) 29 (72.5) 0.5086 � CT 13 (26.0) 10 (25.0)Other 4 (8.0) 1 (2.5)Received radiotherapy 46 (92.0) 38 (95.0) 0.689Received endocrine treatment 45 (90.0) 33 (82.5) 0.358Received trastuzumubab 8 (16.0) 2 (5.0) 0.175 Physical activity level (self-reported) Pre-illness † Sedentary 1 (2.1) 1 (2.8) 0.717 Walking or cycling for pleasure 11 (22.9) 9 (25.0) Regular physical exercise, at least 3 h/week 34 (70.8) 23 (63.9) Intense physical activity � 4 h/week 2 (4.2) 3 (8.3)Present Sedentary 0 (0.0) 1 (2.5) 0.326 Walking or cycling for pleasure 7 (14.0) 10 (25.0) Regular physical exercise at least 3 h/week 25 (50.0) 15 (37.5) Intense physical activity � 4 h/week 18 (36.0) 14 (35.0) Training Performed exercises prescribed post-surgery ‡ No 10 (21.7) 3 (7.7) 0.1923 � weekly 8 (17.4) 7 (17.9)Daily 28 (60.9) 29 (74.4)PRT 1-3x/wk between surgery and ’ Body and Cancer ’ ‡ 13 (28.3) 10 (25.6) 1.000PRT 1-3x/wk 3 months after ’ Body and Cancer ’ 24 (48.0) 22 (55.0) 0.532Utilized 2 – 3 sets of 5 – 8 RM 14 (28.0) 14 (35.0) 0.769Adherence � 70% while in ‘ Body and Cancer ’ 35 (70.0) 19 (47.5) 0.051

∗ [n � 84, (n � 39 BCRL; n � 50 no BCRL)] due to missing data; † (n � 84) due to missing data; ‡ [n � 85,(n � 39 BCRL; n � 46 no BCRL)] participants receiving neo-adjuvant (n � 4) or chemotherapy for advanced disease (n � 1) not included.

[16,17], or bilateral breast cancer [16], or if they had a pre-existing upper limb impairment [16,17]. Furthermore, participants were screened and excluded if they presented with BCRL. In the pres-ent study, none of these exclusion criteria were applied and no pre-intervention BCRL screening took place, thus participants could have initiated B & C with an undiagnosed BCRL. Moreover, BCRL was in focus in the RCTs, and participants received treatment upon any signs or symptoms of BCRL during both the intervention and follow-up periods. This likely decreased the incidence of BCRL in comparison to the present study where participants

were encouraged to seek treatment by the B & C staff upon symptoms of BCRL, but “ were on their own ” after the intervention period.

Measurement methods. It is well established that the diagnostic method used in a given observational or intervention study infl uences the incidence or prev-alence found [3]. This is illustrated in a recent study that found baseline prevalence rates ranging from 22% (arm circumference) to 52% (self-reported swelling) depending on the four measurement meth-ods applied [3]. Similarly, Ahmed et al. reported

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Heavy resistance training and lymphedema 223

baseline BCRL prevalence rates of 17.4% (arm cir-cumference), 43.4% (self-reported swelling), and 30.4% (self-reported clinician diagnosis) [22]. In the present study, under half (47.4%) of the women that had reported a clinician diagnosis of BCRL pre-sented with an interlimb difference � 2 cm at two or more measures, indicating that if this measurement method had been used as the primary measure, prevalence rates had been considerably lower.

Treatment burden. Breast cancer treatment is tailored to the individual breast cancer status, thus women treated for breast cancer is a heterogeneous group [4]. This is exemplifi ed in a Danish population-based study that found that 1 – 3 years post-surgery, BCRL prevalence rates ranged from 13% to 65% based on treatment burden alone [4]. The study illustrates well the complexity regarding overall prevalences in this group, and should be taken into consideration in the interpretation of prevalence and incidence rates.

Known risk factors

In accordance with risk factors identifi ed by Disipio et al. as being supported by a high level of evidence [1], more women in the group diagnosed with BCRL had a current BMI � 25, and had received AND. Moreover, sub-analysis of the AND population revealed that more women had a BMI � 25 at baseline and were currently overweight in the group diagnosed with BCRL. In the total population, more women that had received radiotherapy reported a diagnosis of BCRL. This is also in accordance with Disipio et al. that found a moderate level of evidence support-ing radiotherapy as a risk factor [1]. However, this association was not observed in the AND popula-tion, perhaps due to a small sample size. Nonetheless, these fi ndings are in accordance with results found by Sagen et al. [17], who found that being overweight was the only predictor of developing BCRL among study participants who all had received AND.

An unexpected fi nding, the results showed that more women had received trastuzumubab in the no BCRL group. This difference was not observed in the AND population, however no association to axillary surgery was found. No studies were identi-fi ed by the author that have observed a protective effect of this adjuvant treatment, and as this study is merely a descriptive study with a small population no conclusions can or should be drawn. Rather it should be used as an observation and perhaps a cat-alyst for further study.

Physical activity levels

Questions regarding leisure time physical activity lev-els were validated [21] and had been administered

to participants at the initiation of the B & C training intervention, and could therefore be used to describe any trends in time.

In total 63.1% reported pre-illness physical activ-ity levels corresponding to at least three hours per week, and 7.8% over four hours per week. Physical activity levels at follow-up (4 – 26 months post-intervention) had shifted to an increase in physical activity with 47.0% reporting that they presently were exercising at least three hours per week, and 31.5% exercising over four.

However, these results are likely infl ated due to pleasing bias as approximately half of the partici-pants had previously met the author due to her affi liation with B & C as a trainer. Nonetheless, this is an interesting fi nding as previous studies have found that women who undergo treatment for breast cancer tend to decrease physical activity levels [23]. More importantly this shift was also seen in par-ticipants diagnosed with BCRL, indicating that maintaining and possibly increasing a physically active lifestyle is possible with BCRL. Furthermore, this fi nding indicates that participation in an inten-sive, multimodal, six-week intervention promoting physical activity during adjuvant treatment perhaps can play a role in lasting lifestyle changes.

Post-surgery exercises

Self-reported adherence to post-surgery exercise was high, with 75.2% of the total population and 83.5% of the AND population performing these exercises at least three times per week before initiating B & C. Despite this, 90.2% of the participants that devel-oped BCRL reported that they regularly had performed these exercises, thus no protective effect was indicated. However, post-operative exercises focusing on mobility of the shoulder joint and stretching of muscles related to breast cancer surgery play an important role in restoring normal function of the affected limb [24] and should therefore be an integrated part of a rehabilitation program.

PRT during and after B & C

Strength outcome measures and adherence related to B & C. No between group differences in post-intervention 1 RM strength or adherence were found. These results indicate that there was no difference in strength training intensity between the women that did and did not develop BCRL.

PRT after B & C. Over 50% reported that they had continued to perform PRT 1 – 3 � /week for a mini-mum of three months, with no between group differences. These results are in line with previous

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224 K. Bloomquist et al.

intervention studies, fi nding no associations between PRT and an increased risk of BCRL. Approximately 30% reported that they had lifted loads of 5 – 8 repetitions (heavy), with no between group differ-ences. This fi nding indicates that heavy PRT after B & C was not associated with a self-reported clinician diagnosis of BCRL, however further inves-tigation using a robust design is warranted.

Strengths and limitations

The participants. A total of 83% of the identifi ed B & C participants made up the study population. Twelve women with pre-existing BCRL were excluded as one of the main objectives of the study was to describe association between participation in B & C and the development of BCRL. Thus, when considering the prevalence of BCRL in the study population, these participants should be taken into account.

Moreover, due to ethical considerations, nine women were not contacted as it had been noted in the medical records that a recurrent cancer had recently been detected or was under investigation, and three were deceased. A further two declined to participate for personal reasons, and fi ve were uncontactable. Thus, the BCRL status of these women is not known.

Design. As this study utilized a cross-sectional design, and with a small study sample, it does not offer the possibility of drawing conclusions regarding causal-ity, but can merely describe factors associated with identifi ed cases of BCRL as defi ned in this study. Thus, though results do not indicate an association between heavy resistance training and the develop-ment of BCRL, conclusions regarding the “ safety ” of heavy resistance training cannot be drawn. None-theless, the observations from this study are in line with studies from Cormie et al. [18,19], who found that heavy load PRT was a safe training modality for persons with an existing arm lymphedema, lending credibility to the results of the present study.

Structured telephone interview. The response rate to the telephone interview was high (94.3%). Furthermore, there was a 100% completion rate amongst respond-ers indicating that this was an evident method for obtaining data. The structured telephone interview was designed for the present study and was not vali-dated. Furthermore, some of the questions were ret-rospective in nature, thus a risk of recall bias exists.

BCRL defi nition considerations. Ideally, objective measurements would have been performed on all participants, however, this was beyond the scope of the study and was not possible. Thus, reporting

a clinical diagnosis of BCRL was utilized as the primary defi nition, despite numerous uncertain-ties. Firstly, this provides just one estimate of prev-alence and therefore does not give the possibility to determine whether it was transient lymphedema dissipating over time, or chronic BCRL. A longi-tudinal study (n � 211) evaluating BCRL on fi ve occasions up to 18 months post-surgery, found that almost 60% of the women that had showed evidence of BCRL, had transitory symptoms whereby the lymphedema dissipated [2]. This is important to bear in mind when comparing the follow-up incidence estimates in the Kilbreath and Sagen studies where all participants were evalu-ated anew, whereby transient lymphedema cases were identifi ed and therefore not included as an incident BCRL case. In the present study all BCRL cases were accumulated and thus, the fi nal esti-mated prevalence is likely overestimated. Second, BCRL was determined by at least eight different clinicians, with no standardized protocols, cut-offs or criteria for when a participant presented with BCRL, lending uncertainty as to the real preva-lence in the study population. However, in com-parison to studies with well-defi ned cut-offs and controlled frameworks, the present study is prag-matic and refl ects the reality of clinical practice. Finally, in the present study BCRL was not limited to the arm, and should be considered when inter-preting the results of the study.

Despite the limitations, the present study with its high response rate and 100% completion rate amongst responders, offers conceivable prevalence estimates of BCRL amongst former participants of this exercise intervention. Furthermore, the data obtained are consistent, with no contradictory fi nd-ings, lending credibility to the results.

Studies investigating BCRL are confronted with a number of challenges. Variations in treatment burden alone, infl uence prevalence rates. Moreover utilization of different measurement methods and criteria applied to defi ne chronic BCRL, thwart comparisons between studies and limits the knowl-edge gained, thus international consensus needs to be found. Nonetheless, irrespective of the diagnostic criteria applied, studies have found PRT to be safe following breast cancer, with this study adding to the growing database. There is considerable rational for promoting PRT during adjuvant treatment as PRT performed alone or in combination with other exer-cise modalities has been shown to relieve a number of chemotherapy-induced side effects [9,16,20]. Furthermore, though strength gains are seen with lighter loads, heavy PRT is an effective training method and necessary for achieving strength gains in trained individuals [25].

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Heavy resistance training and lymphedema 225

Conclusion

The prevalence of self-reported clinician diagnosed BCRL, 4 – 26 months after participation in a reha-bilitation exercise intervention utilizing heavy resis-tance training, was 27.5%. Sub-analysis revealed a prevalence rate of 44.4% amongst participants who had undergone axillary node dissection.

There appears to be no association between performing heavy resistance training during adjuvant therapy, and the development of BCRL. However randomized controlled trials should be performed to confi rm this observation.

Acknowledgments

Thanks to all the participants who donated their time and shared their experiences.

Declaration of interest: The authors report no confl icts of interest. The authors alone are respon-sible for the content and writing of the paper.

References

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Battaglini C , Bottaro M , Dennehy C , Rae L , Shields E , [10] Kirk D , et al . The effects of an individualized exercise intervention on body composition in breast cancer patients undergoing treatment . Sao Paulo Med J 2007 ; 125 : 22 – 8 . Winters-Stone KM , Dobek J , Nail L , Bennett JA , Leo [11] MC , Naik A , et al . Strength training stops bone loss and builds muscle in postmenopausal breast cancer survivors: A randomized, controlled trial . Breast Cancer Res Treat 2011 ; 127 : 447 – 56 . Schmitz KH , Ahmed RL , Troxel A , Cheville A , Smith R , [12] Lewis-Grant L , et al . Weight lifting in women with breast-cancer-related lymphedema . New Engl J Med 2009 ; 361 : 664 – 73 . Hayes SC , Reul-Hirche H , Turner J . Exercise and secondary [13] lymphedema: Safety, potential benefi ts, and research issues . Med Sci Sport Exer 2009 ; 41 : 483 – 9 . Baechle TR , Earle RW , Wathen D . Essentials of strength [14] training and conditioning . In: Baechle TR , Earle RW , editors. Human Kinetics , 2nd ed . Champaign IL: National Strength and Conditioning Association ; 2000 . Anderson RT , Kimmick GG , McCoy TP , Hopkins J , [15] Levine E , Miller G , et al . A randomized trial of exercise on well-being and function following breast cancer surgery: The RESTORE trial . J Cancer Surviv 2012 ; 6 : 172 – 81 . Kilbreath SL , Refshauge KM , Beith JM , Ward LC , Lee M , [16] Simpson JM , et al . Upper limb progressive resistance training and stretching exercises following surgery for early breast cancer: A randomized controlled trial . Breast Cancer Res Treat 2012 ; 133 : 667 – 76 . Sagen A , Karesen R , Risberg MA . Physical activity for [17] the affected limb and arm lymphedema after breast cancer surgery. A prospective, randomized controlled trial with two years follow-up . Acta Oncol 2009 ; 48 : 1102 – 10 . Cormie P , Galvao DA , Spry N , Newton RU . Neither heavy [18] nor light load resistance exercise acutely exacerbates lymphedema in breast cancer survivor . Integr Cancer Ther 2013 ; 12 : 423 – 32 . Cormie P , Pumpa K , Galvao DA , Turner E , Spry N , [19] Saunders C , et al . Is it safe and effi cacious for women with lymphedema secondary to breast cancer to lift heavy weights during exercise: A randomised controlled trial . J Cancer Surviv 2013 ; 7 : 413 – 24 . Adamsen L , Quist M , Andersen C , Moller T , Herrstedt J , [20] Kronborg D , et al . Effect of a multimodal high intensity exercise intervention in cancer patients undergoing chemo-therapy: Randomised controlled trial . Br Med J 2009 ; 339 : b3410 . Saltin B , Grimby G . Physiological analysis of middle-aged [21] and old former athletes . Comparison with still active athletes of the same ages. Circulation 1968 ; 38 : 1104 – 15 . Ahmed RL , Thomas W , Yee D , Schmitz KH . Randomized [22] controlled trial of weight training and lymphedema in breast cancer survivors . J Clin Oncol 2006 ; 24 : 2765 – 72 . Irwin ML , Smith AW , McTiernan A , Ballard-Barbash R , [23] Cronin K , Gilliland FD , et al . Infl uence of pre- and postdiagnosis physical activity on mortality in breast cancer survivors: The health, eating, activity, and lifestyle study . J Clin Oncol 2008 ; 26 : 3958 – 64 . McNeely ML , Campbell K , Ospina M , Rowe BH , Dabbs K , [24] Klassen TP , et al . Exercise interventions for upper-limb dysfunction due to breast cancer treatment . Cochrane Database Syst Rev 2010 : CD005211 . American College of Sports Medicine position stand . [25] Progression models in resistance training for healthy adults . Med Sci Sport Exer 2009 ; 41 : 687 – 708 .

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Paper II

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STUDY PROTOCOL Open Access

A randomized cross-over trial to detectdifferences in arm volume after low- andheavy-load resistance exercise amongpatients receiving adjuvant chemotherapyfor breast cancer at risk for armlymphedema: study protocolKira Bloomquist1* , Sandi Hayes2, Lis Adamsen1, Tom Møller1, Karl Bach Christensen3, Bent Ejlertsen4

and Peter Oturai5

Abstract

Background: In an effort to reduce the risk of breast cancer-related arm lymphedema, patients are commonlyadvised to avoid heavy lifting, impacting activities of daily living and resistance exercise prescription. This advicelacks evidence, with no prospective studies investigating arm volume changes after resistance exercise with heavyloads in this population. The purpose of this study is to determine acute changes in arm volume after a session oflow- and heavy-load resistance exercise among women undergoing adjuvant chemotherapy for breast cancer atrisk for arm lymphedema.

Methods/Design: This is a randomized cross-over trial. Participants: Women receiving adjuvant chemotherapy forbreast cancer who have undergone axillary lymph node dissection will be recruited from rehabilitation centers inthe Copenhagen area. Intervention: Participants will be randomly assigned to engage in a low- (two sets of 15–20repetition maximum) and heavy-load (three sets of 5–8 repetition maximum) upper-extremity resistance exercisesession with a one week wash-out period between sessions. Outcome: Changes in extracellular fluid (L-Dex score)and arm volume (ml) will be assessed using bioimpedance spectroscopy and dual-energy x-ray absorptiometry,respectively. Symptom severity related to arm lymphedema will be determined using a visual analogue scale (heaviness,swelling, pain, tightness). Measurements will be taken immediately pre- and post-exercise, and 24- and 72-hourspost-exercise. Sample size: A sample size of 20 participants was calculated based on changes in L-Dex scores betweenbaseline and 72-hours post exercise sessions.

Discussion: Findings from this study are relevant for exercise prescription guidelines, as well as recommendationsregarding participating in activities of daily living for women following surgery for breast cancer and who may be atrisk of developing arm lymphedema.

Trial registration: Current Controlled Trials ISRCTN97332727. Registered 12 February 2015.

Keywords: Lymphedema, Breast cancer, Resistance exercise

* Correspondence: [email protected] Hospitals Centre for Health Research (UCSF), CopenhagenUniversity Hospital, Rigshospitalet, Blegdamsvej 9, 2100 Copenhagen Ø,DenmarkFull list of author information is available at the end of the article

© 2016 The Author(s). Open Access This article is distributed under the terms of the Creative Commons Attribution 4.0International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, andreproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link tothe Creative Commons license, and indicate if changes were made. The Creative Commons Public Domain Dedication waiver(http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.

Bloomquist et al. BMC Cancer (2016) 16:517 DOI 10.1186/s12885-016-2548-y

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BackgroundApproximately 20 % of breast cancer survivors developbreast cancer-related arm lymphedema BCRL [1], withan estimated 80 % of cases presenting within the firsttwo years of diagnosis [2]. It is associated with signifi-cant impairments in gross and fine motor skills affect-ing work, home and personal care functions, as well asrecreational and social relationships [3, 4]. While theetiology of BCRL is unknown [1, 5], findings from asystematic review and meta-analysis from 2013 [1] in-cluding 72 studies demonstrate that axillary lymphnode dissection, more extensive breast surgery, radio-therapy, chemotherapy, being overweight or obese andphysical inactivity are consistently associated with in-creased BCRL risk [1].Participation in resistance exercise has been found

to be a safe and effective exercise modality amongbreast cancer survivors at risk of BCRL [6, 7], and isassociated with increases in lean muscle mass andstrength, which in turn positively effect physical func-tion and ability. Furthermore, findings from a recentmeta-analysis [6] suggest that resistance exercise canreduce the risk of BCRL versus control conditions(OR = 0.53 (95 % CI 0.31–0.91); I2 = 0 %). However, thecurrent evidence-base is derived from studies that haveevaluated resistance exercise intensities considered to below to moderately heavy (60–80 % of 1 repetition max-imum (RM) or 8–15 RM) [6, 7]. Yet, exercise scienceliterature indicates that heavy-load resistance exercise(80–90 % 1RM or 5–8 RM) [8] is more effective than low-to moderate-load resistance exercise in generating musclestrength gains [9]. There is therefore a clear need for stud-ies evaluating the safety of heavy-load resistance exercisein the at-risk population [7].In a novel study by Cormie et al. [10], which evalu-

ated the effect of low- and heavy-load resistance exer-cise among a sample with BCRL, lymphedema statusand lymphedema symptoms remained stable immedi-ately after exercise, and 24- and 72-hours after exercise,irrespective of load. While these findings provide im-portant information for women with BCRL, the pur-pose of this study is to determine acute changes inextracellular fluid, arm volume and associated lymph-edema symptoms after a session of low- and heavy-loadresistance exercise in women at risk for BCRL. It is hy-pothesized that no interlimb differences in extracellularfluid, arm volume or lymphedema-associated symptomseverity will be observed over time or between resist-ance exercise loads.

DesignThis study is a randomized, cross-over trial (Table 1here).

Table 1 Trial registration data

Trial registration data

Primary registry and trialidentify number

Current Controlled Trials ISRCTN97332727.

Date of registration inprimary registry

12 February 2015.

Secondary identifyingnumbers

H-3-2014-147, 30-1430

Source of monetary ormaterial support

University Hospitals Centre for HealthResearch, Copenhagen University HospitalRigshospitalet

Primary sponsor University Hospitals Centre for Health Research,Copenhagen University Hospital Rigshospitalet

Secondary sponsor

Contact for publicqueries

KB, MHS, PhD-stud. [email protected], (45)35347362, Blegdamsvej 9 (afsnit 9701), 2100Copenhagen

Contract for scientificqueries

KB, MHS, PhD-stud. [email protected], (45)35347362, Blegdamsvej 9 (afsnit 9701), 2100Copenhagen

Public title A trial to detect differences in arm volumeafter low- and heavy-load resistance exerciseamong patients receiving adjuvantchemotherapy for breast cancer at riskfor arm lymphedema: Study Protocol

Scientific title A randomized cross-over trial to detectdifferences in arm volume after low- andheavy-load resistance exercise among patientsreceiving adjuvant chemotherapy for breastcancer at risk for arm lymphedema:Study Protocol

Countries ofrecruitment

Denmark

Health condition orproblem studied

Breast cancer-related arm lymphedema

Intervention Heavy vs low load resistance exercise for theupper extremities

Key inclusion andexclusion criteria

Inclusion criteria: > 18 years of age, unilateralbreast surgery, axillary node dissection,undergoing adjuvant chemotherapy for breastcancer

Exclusion criteria: Previously treated for breastcancer, diagnosis of BCRL and/or currentlyreceiving treatment for BCRL, or havingconditions hampering resistance exercise ofthe upper body, or having participated inregular upper-body heavy resistance exerciseduring the last month

Study type Interventional

Randomized cross-over, assessor blinded

Safety

Date of first enrolment 31-03-2015

Target sample size 40

Recruitment status Recruiting

Primary outcome Arm extracellular fluid (L-dex score) post-,24- and 72 h post exercise

Key secondaryoutcomes

Arm volume (ml) post-, 24- and 72 h postexercise

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MethodsParticipants / RecruitmentTwenty women allocated to adjuvant chemotherapy forbreast cancer consisting of three cycles of 3-weekly epiru-bicin followed by three cyles of 3-weekly docetaxel will berecruited from municipality lead rehabilitation centers inthe Copenhagen area and from a waiting list to the Bodyand Cancer program [11, 12], at the University HospitalsCenter for Health Research (UCSF) at the CopenhagenUniversity Hospital, Rigshospitalet. All patients will bescreened for inclusion by health professionals (nurse orphysical therapist) at the respective centers. Potential par-ticipants fulfilling inclusion criteria; over 18 years of age,unilateral breast surgery, axillary node dissection, and ini-tiating /undergoing adjuvant chemotherapy for breastcancer (stage I - III) will be contacted during their firstthree cycles of chemotherapy (Fig. 1). Patients previouslytreated for breast cancer, with a diagnosis of BCRL and/orcurrently receiving treatment for lymphedema, or havingconditions hampering resistance exercise of the upperbody, or having participated in regular (>1 × / week)upper-body heavy resistance exercise during the lastmonth will be excluded.Those fulfilling study criteria and expressing interest

in study participation will thereafter be screened forBCRL by the first author after the third cycle of chemo-therapy, using bioimpedance spectroscopy (BIS). Fur-thermore, in accordance with common toxicity criteria(CTC) v3.0 lymphedema criteria for the limb [13], pa-tients will be visually inspected to detect differences insigns of swelling between arms. Those presenting withBCRL, defined as a lymphedema index (L-Dex) score of10 or greater [14–16] (as assessed by BIS), and/or visualsigns of swelling (obscuration of anatomic architectureor pitting edema) of the at-risk arm [13] will be referredfor treatment, and will not be included in the study.Written and oral information regarding the study will

be delivered by the first author, as well as obtainment ofinformed written consent.

Concealed randomizationPrior to the study, a computer-generated random se-quence will be generated by an external researcher nototherwise affiliated with the study, and concealed inopaque envelopes. Group assignment will be disclosedto the first author by telephone after study inclusion andparticipation in the familiarization period. Participantswill be allocated using a 1:1 ratio to partake in eitherlow- or heavy-load resistance exercise first.

Exercise sessionsParticipants will engage in a familiarization period, com-prising of two training sessions up to one week apart, afterthe third cycle of chemotherapy. Each session will startwith a 10- minute aerobic warm-up using a cross-trainer(Glidex, Technogym®, Gamettola, Italy). During the firstfamiliarization session participants will be introduced tofour upper-body exercises (chest press, latissimus pulldown, triceps extension (Technogym®, Gamettola, Italy)and biceps curl (free weights)) followed by a 1RM strengthtest in each exercise. At the second familiarization session,two sets of 10–15 RM will be performed and a new 1RMstrength test will be undertaken to ensure accuracy of sub-sequent exercise prescription. Participants will engage inthe first experimental session after the first cycle of doce-taxel (fourth chemotherapy), followed by a wash-outperiod of 6 days. Two sets of 15–20 RM of each exercisewill be performed during low-load resistance exercise andthree sets of 5–8 RM during heavy-load. All sets will beperformed to muscle fatigue in sessions individually super-vised by the first author (a physical therapist with experi-ence in exercise prescription for women with breastcancer) at training facilities located at Rigshospitalet.

Outcomes (pre- and post, 24- and 72-hours after resist-ance exercise)Measurements will be performed by medical technicianswith no knowledge of group (low- / high-load first) allo-cation at the Department of Clinical Physiology and

Fig. 1 Study time line

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Nuclear Medicine at the Copenhagen University Hos-pital, Rigshospitalet. Participants are advised to maintaintheir normal activities during study participation. At allassessment points, participants will be asked about theirphysical activities, and any extraordinary activities willbe recorded.

Primary outcomeExtracellular fluid BIS (SFB7, Impedimed, Brisbane,Australia) directly measures the impedance of extracel-lular fluid and has a high reliability for detecting BCRL[14, 16, 17] (intraclass correlation coefficient (ICC) =0,99) [18]. Participants will be positioned in supine witharms and legs slightly abducted from the trunk withpalms facing down. Utilizing the principle of equipoten-tials, four single tab electrodes will be placed in a tetrapo-lar arrangement [17]. Measurement electrodes will beplaced on the dorsum of the wrist midway between thestyloid processes, with current drive electrodes placed fivecentimeters distally on the dorsal side over the third meta-carpal of the hand, and approximately midway on thethird metatarsal on the dorsum of the foot [17, 19]. Eachlimb will be measured at a range of frequencies using themanufacturer’s software. The ratio of impedance betweenthe at-risk and non-affected limb will be calculated andconverted into a L-Dex score.

Secondary outcomesArm volume Dual energy x-ray absorptiometry (DXA)(Lunar Prodigy Advanced Scanner, GE Healthcare,Madison, WI) measures tissue composition using a three-compartment model that is sensitive to changes in upper-limb tissue composition [20, 21]. Using previously deriveddensities for: fat (0.9 g/ml); lean mass (1.1 g/ml); bonemineral content (BMC) (1.85 g/ml), the measured DXAtissue weights will be transformed into estimated arm vol-umes [20, 21].Participants will be positioned on the scan-table, lying

supine with the arm separated from the trunk. If neces-sary a Velcro band will be used over the breast to ensurespace between the arm and truncus. Each arm will bescanned separately. Small animal software (Encore ver-sion 14.10) will be used to analyze the scans as describedby Gjorup et al. [20]. Scans will be point typed wheresoft tissue is marked as bone, whereafter regions ofinterest (ROIs) will be drawn around the hand and thearm on every scan (Fig. 2). All scans will be analyzed byone examiner (last author) with experience in analyzingDXA scans.Subjective assessment of symptoms The severity of symp-

toms related to arm lymphedema including swelling,heaviness, pain and tightness, will be monitored using avisual analogue scale, whereby 0 represents no discomfortand 10 is indicative of very severe discomfort [10].

Fig. 2 DXA regions of interest

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One year follow-upStatistically, it is assumed that some of the participantsin the study will develop arm lymphedema. Furthermore,previous studies have found a highly variable response toresistance exercise [10, 22]. A one year exploratory, hy-pothesis generating follow-up has been planned as itprovides an opportunity to determine how many partici-pants develop arm lymphedema and whether individualvariability in response to the resistance exercise ses-sions is related to subsequent lymphedema incidence.Measurements will include 1RM strength in the fourresistance exercises, DXA, BIS and symptom severity(VAS) as described, and a structured interview by thefirst author to determine other known and theoreticalrisk factors.

BlindingAll data collection and analysis will be conducted bystudy personnel with no knowledge of group (low- /high-load first) allocation.

Sample size and analytical planThe sample size calculation is based on changes in L-Dexscores between baseline and 72 h post-resistance exercisesessions. From results of Cormie et al. [10] we hypothesizethe standard deviation in the distribution to be 1.9 units.No published normative change scores exist for the at-riskpopulation, as well as no evidence regarding a thresholdfor a clinically significant acute change. For patients withBCRL a change score of 2L-Dex units is considered clinic-ally relevant based on clinical experience. We believe thatan L-Dex of 2 units is too conservative in the at-risk popu-lation, and have therefore set a threshold at 3L-Dex units.Thus, if there is no difference between groups, then 18 pa-tients are required to be 90 % sure that the limits of atwo-sided 90 % confidence interval will exclude a differ-ence in means of more than 3.0. To allow for possibledrop-outs we plan to include 20 patients.Data will be analyzed using the Statistical Package for

Social Sciences (SPSS) software (version 19) for Windows(IBM SPSS, Chicago, IL). Analysis will include standarddescriptive statistics and both intention to treat and per-protocol analysis will be performed. Using a generalizedestimating equations framework for continuous outcomesto determine time (baseline, pre-, post, 24- and 72 h) andintervention (low-/ heavy-load) effects, the interactionbetween time and intervention will be considered [23].Two-tailed p < 0.05 will be taken as evidence of statis-tical significance.

Safety and ethical considerationsThe treating oncologist will have the overall responsibil-ity for the participants. All personal data will be treatedin accordance with existing rules and regulations.

A full body DXA scan utilizes weak x-rays and is notconsidered dangerous [24]. In this study, since only armswill be scanned the radiation dose is estimated to be0.0001 mSv for both arms. Eight scans result in a totaldose of 0.0008 mSv, which is less than the backgroundradiation an average person is exposed to in one day inDenmark.As about 20 % of women treated for breast cancer de-

velop BCRL [1], it is expected that some of the partici-pants in this study will develop BCRL. Participation inthis study involves regular assessment of the at-risk armduring the study period, using some of the best technol-ogy to date. This allows for early detection of BCRL,which in turn would render a better prognosis, as earlydetection is associated with a better outcome [4]. If par-ticipants develop signs of swelling or an L-Dex scorepersisting over one week during the familiarization orexperimental study period, they will be referred to thetreating oncologist for lymphedema treatment and willbe withdrawn from the study.A completed SPIRIT checklist is included as Additional

file 1.

DiscussionParticipating in resistance exercise during adjuvant chemo-therapy for breast cancer has been associated with increasesin muscle strength [25–29], lean body mass [25, 28], andself-esteem [25], and has been found to mitigate fatigueand to maintain quality of life [29]. Furthermore, there isevidence to suggest that resistance exercise might be asso-ciated with a higher completion rate of planned chemo-therapy [25]. Moreover, generalized edema characterizedby an increase in the size of the interstitial compartmentof extracellular fluid is a potential side effect to taxane-based chemotherapy [30, 31]. Thus, swelling as a conse-quence of increased fluid in addition to an impairment oflymph fluid transport, could potentially contribute toswelling of the at-risk arm. Hypothetically, this could bethwarted by resistance exercise due to increased lymphclearance likely through the effects of the muscle pump[32, 33], lending additional rationale for instigating resist-ance exercise during adjuvant chemotherapy.To our knowledge, studies investigating the safety and

efficacy of resistance exercise in patients at risk for BCRLhave utilized low- to moderate-resistance exercise inten-sities [6, 7], with only one cross-sectional study [11] inves-tigating heavy-load resistance exercise. Indeed, in a paperidentifying the top 10 research questions related to phys-ical activity and cancer survivorship, Courneya et al. [34]highlighted the need for studies investigating safety andoptimal exercise prescription, and specifically the role ofvigorous-intensity activity, as important research areas [34].The rational for utilizing heavy-load resistance exercise

is supported by exercise science literature that indicates

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that this higher training intensity can lead to additionalbenefits as a dose–response relationship exists betweenthe load of resistance exercise and gains in muscularstructure and function [35, 36]. Furthermore, breast can-cer survivors may suffer from losses of bone mass (par-ticularly those on aromatase inhibitors), at least in partas a result of the catabolic effects of treatment. Resist-ance exercise interventions with lower loads have notyielded significant training effects on bone mineral dens-ity [27, 37]. It has been postulated that the absence of ameasurable effect on bone mass density is related to theadaptive nature of bone that requires heavier loads [37],as heavy-load resistance exercise has been identified asan osteogenic exercise modality in women without can-cer [38]. Thus, establishing the safety of heavy-load re-sistance exercise is prudent and of significance for thebreast cancer population.No standardized measurement method exists to diag-

nose or monitor BCRL [1, 20, 21], with a variety of tech-niques and definitions used. Early BCRL is characterizedby an increase in extracellular fluid. Indirect measure-ment methods such as circumference, water displace-ment, and perometry measure volume of the entire limbto detect small changes in extracellular fluid which ac-counts for approximately 25 % of the total limb, and donot differentiate between tissue types [5, 18]. In contrast,BIS directly measures lymph fluid change by measuringthe impedance to a low level electrical current allowingfor a sensitive [21, 39] and reliable measurement methodto detect extracellular fluid changes among at-risk breastcancer survivors [39]. Furthermore, BIS is fast and easyto administer, and as impedance measures are reportedas an L-Dex value, inherent volume differences associatedwith hand dominance are taken into account [5, 39]. How-ever, BIS loses its sensitivity to monitor BCRL over timeas lymphedema progresses into later stages, whereby theexcess extracellular fluid initially characterizing BCRL isreplaced with adipose tissue [5, 21].DXA is another measurement method that can differen-

tiate between tissue types giving an estimate of BMC, fatmass and lean mass where the lean mass component in-cludes extracellular fluid [20, 21, 40]. DXA has been foundto be sensitive to changes in tissue composition, making itan ideal measurement method to monitor BCRL over timeas fluid components are replaced with adipose tissue. Fur-thermore, DXA allows for analysis of separate regions ofthe arm, of potential clinical importance for patientswhere swelling is confined to a specific region of the armor hand [20, 21, 40, 41]. In this study we scan the armsseparately and use software with a high resolution allow-ing for more precise definition of ROIs and the possibilityto define bone and soft tissue manually as described byGjorup et al., with a low inter-rater variation (ICC ≥,9990)[20]. To the authors’ knowledge, this is the first time that

DXA, with this software, will be used to detect volumechanges in the BCRL at-risk population adding new in-sights into the application of this measurement method.This exploratory study utilizes a cross-over design to de-

termine acute changes in extracellular fluid and arm vol-ume. This design lends more statistical power, with thepractical advantage of a smaller sample size, as between-patient variation is inherently eliminated [42], providing aframework for an efficient comparison between the tworesistance exercise loads. However, this study can onlyprovide us with information regarding extracellular fluidand arm volume changes after one resistance exercise ses-sion, limiting the generalizability to repeated resistance ex-ercise training and long-term effects on arm volume.Nonetheless, this study can lend initial evidence regardingthe safety of heavy-load lifting and can help guide futurestudies and optimal exercise prescription.Finally, women at risk for BCRL still receive risk reduc-

tion advice including avoiding heavy lifting [43, 44]. Thisadvice can lead to women being apprehensive about liftingheavy loads with consequences for daily living (e.g., notlifting children, groceries, etc.). However, this advice is notbased on research and knowledge gained from this studycan provide a preliminary evidence base for guiding riskreduction practices involving intermittent heavy-load ac-tivity necessary for daily living.

Additional file

Additional file 1: SPIRIT checklist. (DOC 121 kb)

AbbreviationsAND, axillary lymph node dissection; BCRL, breast cancer-related armlymphedema; BIS, bioimpedance spectroscopy; CTC, common toxicitycriteria; DXA, dual-energy x-ray absorptiometry; ICC, intraclass correlationcoefficient; L-Dex, lymphedema index; ROI, region of interest

AcknowledgmentsWe would like to thank exercise physiologist Christian Lillelund for hiscontribution to the conception of the study.

FundingThis study is internally funded by the University Hospitals Centre for HealthResearch (UCSF), Copenhagen University Hospital, Rigshospitalet. UCSF is alsothe trial sponsor and play a role in the conception, execution, analysis andinterpretation of data.

Availability of data and materialA data management plan has been approved by the regional Danish DataProtection Agency (30-1430). No data monitoring committee has beenformed for the study.The datasets supporting the conclusions of the study are stored in a securedatabase at the Copenhagen University Hospital, Rigshospitalet and willbecome available as additional files upon publication of a results article.

Authors’ contributionsKB: Conception and design, drafting of manuscript and final approval forpublication. SH: Conception and design, drafting of manuscript and finalapproval for publication. LA: Conception and design, drafting of manuscriptand final approval for publication. TM: Conception and design, drafting ofmanuscript and final approval for publication. KBC: Design and final approval

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for publication. BE: Design and final approval for publication. PO: Conceptionand design, drafting of manuscript and final approval for publication.

Authors’ informationKB: PhD-student, MHS, PTSH: Professor, Principal research fellow, PhDLA: Professor, PhD, RN, SociologistTM: Associate Professor, PhD, MPH, RNKBC: Associate Professor, StatisticianBE: Professor, Chief PhysicianPO: Chief Physician

Competing interestsThe authors declare that they have no competing interests.

Consent for publicationNot applicable

Ethics approval and consent to participateThis study has been approved by the Danish Capital Regional EthicsCommittee (H-3-2014-147). All participants will provide written informedconsent.If protocol modifications are necessary, amendments to the trial registrieswill be made after approval from the ethics committee.

DisseminationResults from the trial will be disseminated through publication andpresentation at relevant conferences and seminars regardless of themagnitude or direction of effect.

Author details1University Hospitals Centre for Health Research (UCSF), CopenhagenUniversity Hospital, Rigshospitalet, Blegdamsvej 9, 2100 Copenhagen Ø,Denmark. 2Institute of Health and Biomedical Innovation, QueenslandUniversity of Technology, 60 Musk Avenue, Kelvin Grove Urban Village, KelvinGrove, Queensland 4059, Australia. 3Department of Public Health; Section ofBiostatistics, University of Copenhagen, Øster Farimagsgade 5, 1014Copenhagen K, Denmark. 4DBCG, Afsnit 2501, Copenhagen UniversityHospital, Blegdamsvej 9, 2100 Copenhagen Ø, Denmark. 5Department ofClinical Physiology, Nuclear Medicine and PET, Copenhagen UniversityHospital, Blegdamsvej 9, 2100 Copenhagen, Denmark.

Received: 28 December 2015 Accepted: 11 July 2016

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Paper III

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Heavy-Load Lifting: Acute Response in BreastCancer Survivors at Risk for Lymphedema

KIRA BLOOMQUIST1, PETER OTURAI2, MEGAN L. STEELE3, LIS ADAMSEN1, TOM MKLLER1,KARL BANG CHRISTENSEN4, BENT EJLERTSEN5, and SANDRA C. HAYES3

1University Hospitals Centre for Health Research (UCSF), Copenhagen University Hospital, Copenhagen, DENMARK;2Department of Clinical Physiology, Nuclear Medicine and PET, Copenhagen University Hospital, Copenhagen, DENMARK;3Institute of Health and Biomedical Innovation, School of Public Health and Social Work, Queensland University of Technology,Kelvin Grove, Queensland, AUSTRALIA; 4Department of Public Health, Section of Biostatistics, University of Copenhagen,Copenhagen, DENMARK; and 5DBCG, Afsnit 2501, Copenhagen University Hospital, Copenhagen, DENMARK

ABSTRACT

BLOOMQUIST K., P. OTURAI, M. L. STEELE, L. ADAMSEN, T. MKLLER, K. B. CHRISTENSEN, B. EJLERTSEN, and S. C.

HAYES. Heavy-Load Lifting: Acute Response in Breast Cancer Survivors at Risk for Lymphedema. Med. Sci. Sports Exerc., Vol. 50,

No. 2, pp. 187–195, 2018. Purpose: Despite a paucity of evidence, prevention guidelines typically advise avoidance of heavy lifting in

an effort to protect against breast cancer–related lymphedema. This study compared acute responses in arm swelling and related

symptoms after low- and heavy-load resistance exercise among women at risk for lymphedema while receiving adjuvant taxane-based

chemotherapy. Methods: This is a randomized, crossover equivalence trial. Women receiving adjuvant taxane-based chemotherapy for

breast cancer who had undergone axillary lymph node dissection (n = 21) participated in low-load (60%–65% 1-repetition maximum,

two sets of 15–20 repetitions) and heavy-load (85%–90% 1-repetition maximum, three sets of 5–8 repetitions) upper-extremity resistance

exercise separated by a 1-wk wash-out period. Swelling was determined by bioimpedance spectroscopy and dual-energy x-ray absorp-

tiometry, with breast cancer–related lymphedema symptoms (heaviness, swelling, pain, tightness) reported using a numeric rating scale

(0–10). Order of low- versus heavy-load was randomized. All outcomes were assessed before, immediately after, and 24 and 72 h after

exercise. Generalized estimating equations were used to evaluate changes over time between groups, with equivalence between resistance

exercise loads determined using the principle of confidence interval inclusion. Results: The acute response to resistance exercise was

equivalent for all outcomes at all time points irrespective of loads lifted, with the exception of extracellular fluid at 72 h after exercise

with less swelling after heavy loads (estimated mean difference, j1.00; 95% confidence interval, j3.17 to 1.17). Conclusions: Low-

and heavy-load resistance exercise elicited similar acute responses in arm swelling and breast cancer–related lymphedema symptoms in

women at risk for lymphedema receiving adjuvant taxane-based chemotherapy. These represent important preliminary findings, which

can be used to inform future prospective evaluation of the long-term effects of repeated exposure to heavy-load resistance exercise. Key

Words: ARM SWELLING, BREAST CANCER, DOSE–RESPONSE, STRENGTH TRAINING

Breast cancer–related arm lymphedema (BCRL) is achronic condition initially characterized by regionalswelling of the arm or hand due to increases in

protein-rich extracellular fluid, affecting approximately 20%

of breast cancer survivors as a consequence of treatment(1,2). The adverse effects of BCRL are well described in theliterature, negatively affecting daily functions (3,4) and so-cial, emotional, and psychological well-being (4,5).

More extensive surgery to the chest wall, radiotherapy,chemotherapy, and being overweight and/or physically in-active have been consistently associated with increasedBCRL risk (1). However, the extent of lymph node removalis considered the strongest risk factor, with BCRL incidencefour times higher after axillary lymph node dissectioncompared with sentinel-node biopsy (1). Despite the high-quality evidence in support of specific risk factors, theability to predict who will develop BCRL is limited.

Historically, breast cancer survivors were advised to re-frain from resistance exercise as a means of preventingBCRL (6,7). However, results from systematic reviews ofclinical trials consistently indicate that resistance exerciseelicits gains in muscle strength and physical componentsof quality of life without increased risk for BCRL (6–9).

Address for correspondence: Kira Bloomquist, M.H.S, P.T., University Hospi-tals Centre for Health Research (UCSF), Copenhagen University Hospital,Blegdamsvej 9, 2100 Copenhagen, Denmark; E-mail: [email protected] for publication July 2017.Accepted for publication September 2017.

0195-9131/18/5002-0187/0MEDICINE & SCIENCE IN SPORTS & EXERCISE�Copyright� 2017 The Author(s). Published by Wolters Kluwer Health, Inc.on behalf of the American College of Sports Medicine. This is an open-access article distributed under the terms of the Creative CommonsAttribution-Non Commercial-No Derivatives License 4.0 (CCBY-NC-ND),where it is permissible to download and share the work provided it is properlycited. The work cannot be changed in any way or used commercially withoutpermission from the journal.

DOI: 10.1249/MSS.0000000000001443

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Nonetheless, more work needs to be undertaken to confirmsafety of resistance exercise, because those considered at highrisk for BCRL do not reflect the target sample of studies in-cluded in these reviews. Specifically, only one study explic-itly included participants undergoing chemotherapy (10), ofwhich 31% received adjuvant taxane-based chemotherapy.This is of importance because generalized edema with ensu-ing arm swelling is a known side effect to this cytostatic agent(11). In addition, just two studies (10,12) specifically in-cluded women at risk for BCRL who had undergone axillarylymph node dissection, considered the greatest risk factor.

Limitations also exist with respect to exercise prescrip-tion because resistance load has not exceeded 80% of 1-repetition maximum (RM) or 8–12 repetitions in previousstudies evaluating resistance exercise and BCRL risk, be-cause of concerns that heavier loads would trigger BCRLdevelopment (6–9,13). However, exercise science literatureindicates that a dose–response relationship exists betweenloads lifted and gains in muscular structure and functionwith heavier loads shown to be more effective in elicitingstrength gains compared with lighter loads (14,15).

To date, two prospective studies including women withclinically stable BCRL who had been diagnosed with breastcancer at least a year before study inclusion have evaluatedthe potential of heavier-load resistance exercise using 6–10 RM (16,17). These studies found that the extent of armswelling and associated BCRL symptoms remained stableboth immediately after and 24 and 72 h after one bout ofresistance exercise (16), and after 12 wk of regular resistanceexercise irrespective of whether low or heavy loads werelifted (17). As such, these studies provide meaningful infor-mation for women with BCRL who have completed activetreatment (chemotherapy and radiotherapy). These findingscannot, however, be generalized to the at-risk populationundergoing taxane-based chemotherapy.

Therefore, the purpose of this study was to undertake aphase II trial to assess the initial lymphatic response to low-load compared with heavy-load resistance exercise in breastcancer survivors at risk for BCRL development. This wasundertaken by comparing acute changes in extracellular fluid,arm volume, and associated BCRL symptoms after a sessionof low- and heavy-load resistance exercise in women whohad undergone axillary lymph node dissection and were re-ceiving taxane-based chemotherapy during the conduct ofthis trial.

METHODS

Trial Design

Details of study design and methods have been previouslydescribed (18). In summary, this was a randomized, cross-over, equivalence trial whereby women participated in anexperimental low- and heavy-load upper-extremity resis-tance exercise session, with a 7-d wash-out period betweensessions (Fig. 1). It was hypothesized that response would be

similar between resistance exercise loads for all outcomes.The study protocol was approved by the Danish Data Pro-tection Agency (30-1430) and the Danish Capital RegionalEthics Committee (H-3-2014-147), and written informedconsent was obtained from all participants.

Participants

A convenience sample of women receiving standard ad-juvant chemotherapy for stage I–III breast cancer werescreened for eligibility (918 yr of age, first diagnosis ofbreast cancer, unilateral breast surgery, axillary node dis-section) at the Copenhagen Centre for Cancer and Healthand from a wait list to the Body & Cancer program (18,19)at the University Hospitals Centre for Health Research be-tween March 2015 and December 2016. Women with aknown clinical diagnosis of lymphedema or who had con-ditions limiting resistance exercise of the upper extremities(e.g., fibromyalgia, frozen shoulder) or who had participatedin regular upper-extremity heavy resistance exercise (91 perweek) during the last month were excluded (Fig. 1).

Those meeting eligibility were assessed for BCRL statusby the first author (K.B.), after the third cycle of chemo-therapy. BCRL was assessed using bioimpedance spectros-copy (BIS; SFB7; Impedimed, Brisbane, Australia [16,20,21])and a visual inspection to detect differences in swelling be-tween arms (Common Toxicity Criteria v3.0 [2]). Those withevidence of lymphedema according to standardized protocolsfor BIS (L-Dex 910) or visual inspection were then referredto a lymphedema therapist for further assessment and wereexcluded from participating in the study.

Exercise Sessions

All participants completed two familiarization sessions,followed by two experimental sessions (low- and heavy-loadsessions) at exercise facilities located at the research center.

All resistance exercise sessions lasted approximately 30 minincluding a 10-min aerobic-based warm-up (rowing orcross-trainer) at low-moderate intensity. All sessions weresupervised by the first author (K.B.) to ensure consistency ofwarm-up intensity and order of resistance exercises performed.None of the participants wore compression sleeves. Duringthe first familiarization session, participants were introducedto four upper-extremity exercises consisting of the biceps curlperformed with free weights, followed by the chest press,latissimus pull down, and triceps extension using resistanceexercise machines (Technogym�, Gamettola, Italy). Hereaf-ter, a 1RM strength test was performed in each exercise.During the second session, one set of 10–15 repetitions wasperformed, followed by a new 1RM strength test. Subse-quent resistance exercise prescription during the experi-mental sessions was based on these values. After completionof the familiarization sessions, resistance exercise load orderfor the experimental sessions was randomly allocated (i.e.,low or heavy load first) using a computer-generated random

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sequence (1/1 ratio). Women then participated in the experi-mental sessions, which entailed the 10-min aerobic-basedwarm-up, followed by the four resistance-based exercises.Resistance exercise load corresponded to 60%–65% 1RM(two sets of 15–20 repetitions) for the low-load session and85%–90% 1RM (three sets of 5–8 repetitions) for the heavy-load session. Participants were instructed to work to musclefatigue (until they were unable to maintain appropriate tech-nique) within the prescribed range and with rest periods of60–90 s between sets.

The experimental sessions were consistently performedon the same day of the week and at the same time of day,with all outcomes assessed before, immediately after (within30 min), and 24 and 72 h after resistance exercise sessions.Blinded data collection was performed by medical technicians.Participants were instructed to maintain normal upper-body

activities during the experimental period and to refrain fromextraordinary activities involving the upper extremities.

Primary Outcome

Extracellular fluid. BIS was used to directly measureand compare the impedance of extracellular fluid in the up-per extremities to electrical currents at a range of frequenciesaccording to the manufacturer_s software (20,21). Using theprinciple of equipotentials, four single-tab electrodes wereplaced in a tetrapolar arrangement and participants weremeasured in supine, with arms and legs abducted from thetrunk with palms facing down. To ensure accuracy, standardprotocols from the manufacturer were followed (e.g., emptybladder, no excessive exercise or caffeine consumptionwithin 2 h). The ratio of impedance (at R0) between the at-risk

FIGURE 1—Participant flow through resistance exercise and data collection sessions. RE, resistance exercise; SNB, sentinel-node biopsy.

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and nonaffected arm was calculated and converted into anL-Dex score taking arm dominance into account.

Secondary Outcomes

Interarm volume percent difference. Measurementsof arm volume were obtained using dual-energy x-ray ab-sorptiometry (DXA; Lunar Prodigy Advanced Scanner; GEHealthcare, Madison, WI). DXAmeasures tissue compositionusing a three-compartment model that is sensitive to changesin upper-extremity tissue composition (21,22). Using previouslyderived densities for fat (0.9 gImLj1), lean mass (1.1 gImLj1)and bone mineral content (1.85 gImLj1), DXA measure-ments were converted into estimated arm volumes. Lyingsupine on the scan table with the arm separated from thetrunk, each arm was scanned separately. If necessary, a Velcroband or the free arm was placed over the breast to ensure spacebetween the arm and trunk. Small animal software (ENCOREversion 14.10) was used to analyze the scans as described byGjorup et al. (21,22). All scans were analyzed by a clinical ex-pert (P.O.) in DXA scan analysis. Interarm volume percent dif-ferences (at-risk arm minus unaffected arm/unaffected arm �100) were then calculated for each participant.

Subjective assessment of BCRL symptoms. Theseverity of symptoms related to BCRL was monitored usinga numeric rating scale. Participants rated their perceptions ofswelling, heaviness, pain, and tightness independently foreach arm on a scale from 0 (no discomfort) to 10 (very se-vere discomfort) (16,23).

Sample Size Calculation

Sample size calculation was based on changes in L-Dexscores between baseline and 72 h after resistance exercisesessions. From the results of Cormie et al. (16), it was hy-pothesized that the SD in the distribution of L-Dex scoreswould be 1.9 units. On the basis of clinical experience, forpatients with BCRL, a change score of 2.0 L-Dex units wouldbe considered clinically relevant. However, in the at-riskpopulation, no published normative change scores exist, nordoes evidence regarding a threshold for a clinically significantacute change. A change in 2.0 L-Dex units was deemed toosmall in the at-risk population, on the basis of the assumptionthat larger fluctuations would be seen within the normal rangewithout clinical relevance. Therefore, a priori, we set theclinically relevant threshold for change as being 3.0 L-Dexunits. Thus, if there was no difference between intensities,then 18 participants were needed to be 90% sure that thelimits of a two one-sided 95% confidence interval (CI) wouldexclude a difference in means of more than 3.0 L-Dex units.To allow for dropouts, 21 women were recruited.

Statistical Analyses

Descriptive statistics included counts (and percentages) forcategorical values and mean T SD for normally distributedcontinuous variables, unless otherwise noted. Individual

responses to resistance exercise loads were first assesseddescriptively, including determination of the proportion thatexceeded the predetermined clinically relevant threshold.Next, generalized estimating equations (GEE) (24) wereused to evaluate the effects of time (pre-, post-, 24 and 72 hpost-) and load (low/heavy load), and a time–load interac-tion. An exchangeable correlation structure was used tomodel the within-subject correlation of repeated measure-ments over time and across intensities.

To assess equivalence, the principle of CI inclusion wasused to calculate one-sided upper and lower 95% confidencelimits for all outcomes (25) (reported as two-sided 90%confidence limits). If the interval between the upper andlower confidence limits was within the predeterminedequivalence margin, equivalence between resistance exer-cise intensities was declared. For the primary outcome, themargin of equivalence was set at T3.0 L-Dex units. On thebasis of the findings by Stout et al. (26) that volume in-creases of 93% from preoperative measures were indicativeof subclinical BCRL, an equivalence margin of T3.0% wasused for interarm volume percent differences. For all sub-jective measures, interarm differences were calculated andan equivalence margin was set at T1.0 points. This thresholdwas based on previous findings that suggest a 2-point or30% change to be clinically meaningful for pain (23). Per-protocol principles were applied because this is consideredthe most conservative approach for determining equivalence (27).Analyses were conducted in R version 3.3.1 (28) using geepack1.2.0.1 for GEE modeling (29).

RESULTS

Participants. From the 216 women assessed for eligi-bility, 21 were eligible and consented to participate. Ofthese, 3 dropped out before initiation of the experimentalexercise sessions because of time constraints and injury (Fig. 1),1 discontinued participation after the 24-h postexercise as-sessment in week 1 because of logistical considerations, and17 (81%) completed all data collections.

Characteristics of the study population are presented inTable 1. Average age of participants was 45 yr, and meanbody mass index (BMI) was 25.3 kgImj2, with 11 (53%)participants presenting with a BMI of Q25.0 kgImj2. On av-erage, women had 22 axillary lymph nodes removed duringaxillary node dissection and 62% of the participants had re-ceived a mastectomy. As per eligibility criteria, all partici-pants received adjuvant taxane-based chemotherapy duringthe experimental sessions; however, the first 10 participantsreceived docetaxel, whereas the last 11 received paclitaxel,because standard chemotherapy changed midway through thestudy period.

Individual responses to resistanceexercise sessions.For L-Dex and interarm volume outcomes, individual re-sponses to resistance exercise sessions varied with no apparentgroup trend observed (Fig. 2A, B). For BCRL symptoms, wefound that most participants were asymptomatic before

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exercise and remained asymptomatic throughout the subse-quent data collections irrespective of loads lifted (Fig. 2C–F).

Deviations from predetermined thresholds. Whendata were described according to clinically relevant changesfrom preexercise, 16 women (89%) had experienced fluc-tuations in extracellular fluid beyond the predeterminedthreshold at one time point or more, ranging from j8.7 to6.8 L-Dex units. Almost twice as many had fluctuationsafter the low-load session (n = 12 (71%)) compared with thehigh-load session (n = 8 (44%); Table 2). Increases abovethe clinical threshold were observed for seven women (41%)after the low-load session, two of which had increased pre–post measures that remained elevated above the clinicallymeaningful threshold at 24 and 72 h after exercise (Fig. 2A).None of these women had clinically meaningful increases inL-Dex after heavy-load resistance exercise. Four women(22%) had increases in L-Dex after the heavy-load session.Of these, two were observed immediately after the heavyload session (one of these also showed an increase ininterarm volume percent difference; increases had dissipatedin both cases by the 24-h post–follow-up), whereas the othertwo were observed at 72 h after exercise.

For interarm volume, four (24%) women experiencedclinically meaningful fluctuations ranging from j4.1% to4.6%. Three (18%) participants experienced increases afterheavy-load exercise, with two seen immediately after exer-cise and one at 24 h after exercise (Fig. 2B). One participant(6%) experienced decreases after the low-load session im-mediately after exercise (Table 2). None of these observa-tions coincided with other outcome measures (except for thepreviously described L-Dex pre–post measure).

For BCRL symptoms, we found that eight (44%) womenresponded with fluctuations ranging from j7 to 3 units.Specifically, six (33%) women reported decreases in symp-toms, with reductions observed after exercise and sustainedover the subsequent time points, and were equally distrib-uted between resistance exercise load conditions (Table 2).

Increases in symptoms were reported by two (11%) women.One woman reported increases in pain and tightness at 24-hpost–heavy-load exercise (Fig. 2D, E), whereas the other par-ticipant experienced increases in heaviness and swelling afterexercise after the heavy-load session (Fig. 2C, F), and an in-crease in pain 24 h after the low-load session (Fig. 2D). Noneof these increases were sustained at the 72-h postsessionfollow-up.

An overview of unadjusted means and SD for all out-comes at each time point is presented in Table 3.

L-Dex. The estimated mean difference between re-sistance exercise loads and associated two-sided 90% CI forL-Dex scores were contained within the predeterminedequivalence margin of T3.0 units immediately and 24 h afterresistance exercise indicating equivalence between intensi-ties (j0.97 (j2.09 to 0.16) and j0.14 (j1.63 to 1.35),respectively; Table 4). However, at 72 h after exercise, thelower CI exceeded j3.0 and equivalence between low- andheavy-load intensities could not be declared, favoring heavy-load resistance exercise.

Interarm volume percent difference. Equivalence be-tween intensities was observed at all time points for interarmvolume percent differences, as estimated mean differences and90% CI were within the T3.0 margin of equivalence (Table 4).

BCRL symptoms. Equivalence between resistance exer-cise intensities was found for all BCRL symptoms at all timepoints, as estimated mean differences and associated 90% CIwere within the equivalence margin of T1.0 (Table 4).

No adverse events related to exercise (i.e., sprains orstrains) were reported. However, two (11%) participants wereadvised to seek evaluation by a lymphedema therapist at theend of the study period because L-Dex scores had exceeded10 (Fig. 2A). One participant had a preexercise L-Dex scoreof 7.9 in week 1. Upon instigating the low-load session atweek 2, an L-Dex score of 11.7 was observed, with subse-quent measures decreasing. The other participant initiated theheavy-load session at week 1 with a preexercise L-Dex scoreof 3.8, and subsequent measures fluctuating less than 5.0 units.At week 2, a preexercise L-Dex score of 9.5 was observed thatincreased to 12.7 after exercise, with decreasing subsequentmeasures. Notably, this participant suffered from rapid weightgain due to generalized edema between weeks 1 and 2 that waseffectively treated with diuretics. All other outcomes werewithin the predetermined clinical thresholds at all time pointsfor both of these participants.

DISCUSSION

The findings of this study support the hypothesis that acutechanges in extracellular fluid, arm volume, and BCRL-relatedsymptoms were similar irrespective of whether low- orheavy-load upper-extremity resistance exercise was performedduring adjuvant taxane-based chemotherapy in women withaxillary lymph node dissection.

This is the first study to prospectively investigate lym-phatic response to resistance exercise with heavy loads

TABLE 1. Baseline characteristics of participants (n = 21).

Variables Mean T SD/Median (Range)

Age, yr 45.3 T 9.2/46 (23–60)BMI, kgImj2 25.3 T 4.7Cancer stage, n (%)

II 15 (71)III 6 (29)

Tumor size, mm 21.5 T 12.9/18 (7–62)Breast surgery, n (%)

Lumpectomy 8 (38)Mastectomy 13 (62)

Surgery on dominant side, n (%) 11 (52)Axillary lymph nodes removed 21.7 T 7.8Metastatic lymph nodesa 5.7 T 7/2 (1–25)Seroma drainage 5.5 T 3.4Chemotherapy, n (%)

3-wk CE � 3 Y 3-wk docetaxel � 3 10 (48)3-wk CE � 3 Y 1-wk paclitaxel � 9 11 (52)

Axillary webbing at screening, n (%) 8 (38)L-Dex at screening j0.08 T 2.23

aMicrometastase and macrometastase.CE, cyclophosphamide and epirubicin.

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(85%–90% 1RM, for 5–8 repetitions) in breast cancer sur-vivors at risk for developing BCRL. Findings are consistentwith observations from a cross-sectional study (n = 149) thatshowed no association between participation in a multi-modal exercise intervention including heavy-load resistanceexercise during taxane-based chemotherapy and BCRL de-velopment (30). Furthermore, our results are consistent withthe findings of Cormie et al. (16), demonstrating that par-ticipation in a bout of resistance exercise using 6–10RM

loads did not acutely exacerbate swelling or BCRL symp-toms in women with stable lymphedema. As such, this lendscredibility to the results of the present study.

The equivalence design was considered the most appro-priate for addressing our research question and was formal-ized by defining equivalence margins for all outcomes.Equivalence margins ideally represent the maximum clini-cally acceptable difference that one is willing to accept inreturn for the secondary benefits of a new therapy (27),

FIGURE 2—Individual response related to low- and heavy-load resistance exercise sessions for all outcomes (n = 17). A, Heavy-load L-Dex pre-, post-,and 24 h (n = 18). In subplots C–F, heavy-load breast cancer–related lymphedema symptoms preexercise and postexercise (n = 18). n refers to thenumber of participants with a symptom score of 0 at all time points.

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which in this study was heavy-load resistance exercise. Thevalue and impact of establishing equivalence depend on howwell the equivalence margin can be justified in terms ofrelevant evidence and clinical judgment, where a narrowerequivalence margin makes it more difficult to establishequivalence (27). The equivalence margin for the primaryoutcome was estimated as 3.0 L-Dex units. A priori, thethreshold was chosen on the basis of change scores consid-ered to be clinically relevant for persons with BCRL, be-cause no known normative change scores existed for personswithout BCRL. However, new normative data recentlypublished indicate that L-Dex scores fluctuate between 9and 11 units (31). This is in line with our results, finding that16 (89%) participants experienced deviations from the pre-determined L-Dex threshold. As such, although the equi-valence margin for this outcome likely was unnecessarilynarrow, this adds confidence to our findings. Furthermore,had we used broader L-Dex equivalence margins, the 90% CI

at 72 h after exercise would have fallen within the margin ofequivalence. Therefore, in light of these new normative data,it is likely that response to resistance exercise intensities wasequivalent at all time points.

Equivalence was also established for all assessed BCRLsymptoms at all time points, and although fluctuations be-yond the predetermined thresholds were observed, it shouldbe highlighted that the majority (82%) of these deviationsindicated reductions in severity after resistance exercise withboth intensities. This is relevant because symptoms can bethe earliest indicator of an ensuing BCRL (32).

When interpreting the findings, several limitations shouldbe considered. In this study, participants were excluded ifthey presented with evidence of BCRL according to stan-dardized protocols for BIS (L-Dex 910) or visual inspection.It is, however, possible that these women were experiencingtransient increases in extracellular fluid, either as a conse-quence of surgery or in response to chemotherapy (33), and/ormay have been at greatest risk for developing BCRL. Assuch, these women may have been more likely than thoseincluded in the study to demonstrate changes in extracellularfluid, and by excluding them, it may have been easier to findequivalence between loads. Moreover, activities undertakenby participants within the 3 d after the bout of low- or high-load resistance may have influenced data collected at 24 or72 h post–exercise session. However, participants were ad-vised to maintain normal activities throughout the studyperiod, and efforts were made to standardize treatment bur-den by placing exercise bouts and consecutive data collec-tions between chemotherapy cycles.

Strengths of this study include that all participants had re-ceived axillary node dissection, considered the largest singlerisk factor for developing BCRL, lending generalizability to

TABLE 4. Equivalence between resistance exercise intensities for all outcomes (n = 17).

Estimated Mean Differenceb Equivalence 90% CI

L-Dex (T3.0)a

Postexercise j0.97 j2.09 to 0.1624 h postexercise j0.14 j1.63 to 1.3572 h postexercise j1.00 j3.17 to 1.17

Interarm volume % difference (T3.0)a

Postexercise 0.21 j0.89 to 1.3124 h Postexercise 1.09 0.41 to 1.7872 h Postexercise 0.96 j0.09 to 2.02

Interarm difference for pain (T1.0)a

Postexercise 0 j0.43 to 0.4324 h postexercise j0.06 j0.58 to 0.4672 h postexercise j0.06 j0.61 to 0.49

Interarm difference for heaviness (T1.0)a

Postexercise 0.24 j0.23 to 0.7024 h postexercise 0.18 j0.32 to 0.6772 h postexercise 0.24 j0.38 to 0.85

Interarm difference for tightness (T1.0)a

Postexercise j0.06 j0.45 to 0.3424 h postexercise j0.11 j0.50 to 0.2772 h postexercise 0.20 j0.37 to 0.77

Interarm difference for swelling (T1.0)a

Postexercise 0 j0.33 to 0.3324 h postexercise 0 j0.33 to 0.3372 h postexercise 0.06 j0.42 to 0.54

Boldface indicates that equivalence was not demonstrated.aEquivalence margin.bEstimated mean difference calculated using a GEE model with heavy load as comparator(heavy minus low).

TABLE 2. Number (%) of participants exceeding equivalence margin from preexercise toimmediately postexercise and 24 and 72 h after exercise for all outcomes (n = 17).

¸ Pre–Post ¸ Pre–24 h Post ¸ Pre–72 h Post

L-DexHeavy load 2j (11%)a 2, (11%)a 2j (12%), 3, (18%)Low load 4j (24%), 1, (6%) 3j (18%), 4, (24%) 4j (24%), 4, (24%)

% interarm differenceHeavy load 2j (12%) 1j (6%) 1j (6%)Low load 1, (6%) 0 1, (6%)

PainHeavy load 2, (11%)a 1j (6%), 2, (12%) 2, (12%)Low load 2, (12%) 1j (6%), 1, (6%) 1, (6%)

HeavinessHeavy load 1j (6%), 1, (6%)a 1, (6%) 2, (12%)Low load 2, (12%) 2, (12%) 2, (12%)

TightnessHeavy load 0a 1j (6%), 1, (6%) 1, (6%)Low load 1, (6%) 1, (6%) 2, (12%)

SwellingHeavy load 1j (6%), 1, (6%)a 1, (6%) 1, (6%)Low load 0 1, (24%) 2, (12%)

j, higher than equivalence margin; ,, lower than equivalence margin.an = 18.

TABLE 3. Extent of swelling and breast cancer–related lymphedema symptoms for alloutcomes (n = 17).

Preexercise Postexercise24 h

Postexercise72 h

Postexercise

L-Dex scoreHeavy load 1.7 T 3.3a 1.9 T 3.4a 1.0 T 2.6a 0.8 T 3.9Low load 0.8 T 5.0 1.9 T 5.1 0.2 T 4.4 0.7 T 3.6

% interarm differenceHeavy load 0.5 T 4.4 1.0 T 4.0 1.4 T 4.2 1.1 T 4.3Low load 1.3 T 4.1 1.6 T 4.8 1.0 T 4.2 0.8 T 4.4

PainHeavy load 0 (j1, 6)a 0 (j1, 2)a 0 (j1, 3) 0 (0, 2)Low load 0 (0, 5) 0 (j1, 1) 0 (j1, 2) 0 (j1, 4)

HeavinessHeavy load 0 (0, 2)a 0 (0, 4)a 0 (0, 2) 0 (0, 2)Low load 0 (0, 5) 0 (0, 3) 0 (0, 2) 0 (0, 2)

TightnessHeavy load 0 (0, 6)a 0 (0, 5)a 0 (0, 3) 0 (0, 3)Low load 0 (0, 7) 0 (0, 8) 0 (0, 8) 0 (0, 3)

SwellingHeavy load 0 (0, 2)a 0 (0, 3)a 0 (0, 2) 0 (0, 2)Low load 0 (0, 2) 0 (j1, 3) 0 (0, 2) 0 (0, 2)

L-Dex and interarm volume presented as mean T SD. BCRL-related symptoms presentedas median (range).an = 18.

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breast cancer survivors at BCRL risk. Furthermore, becauseall exercise sessions took place during the taxane-based cy-cles of chemotherapy, the results extend to acute bouts oflow- or high-load resistance-type activities during taxane-based treatment. Finally, validated objective measurementmethods sensitive to changes in extracellular fluid were used,and all data collections and analyses were blinded to resis-tance load lending credibility to the results.

Findings from this study are clinically relevant for anumber of reasons. First, the safety of resistance exercise inregard to BCRL risk has previously been established on thebasis of exercise prescription using low- to moderate loads.For example, some resistance exercise programs started withlittle or no weight and slowly progressed with the smallestweight increment possible until loads lifted corresponded toweights that successfully could be lifted a minimum of 15repetitions (12) or within a range of 10–12 repetitions (34),whereas others used loads corresponding to 60%–80% 1RMat 8–12 repetitions (10,13). As such, this work adds newinformation, providing initial evidence that resistance exer-cise prescription also can include heavier loads, specificallycorresponding to 85%–90% 1RM at 5–8 repetitions.

Second, a considerable rationale exists for participatingin resistance exercise during chemotherapy because it hasbeen found to elicit increases in muscle strength (10,35,36),lean body mass (10), and self-esteem (10) as well as at-tenuating fatigue and quality of life (36). Moreover, it hasbeen hypothesized that resistance exercise reduces taxane-related edema (37) through the effects of the muscle pump,and it is plausible that participation in heavy-load resistanceexercise may instigate more effective lymphatic functionchange than low-load resistance exercise, and in doing so,potentially have a greater effect on reducing BCRL risk. Assuch, results from this study provide the necessary platformfor future studies to explore whether additional benefits canbe gained from repeated bouts of heavy-load resistance

exercise during adjuvant taxane-based chemotherapy. Fi-nally, breast cancer survivors commonly receive risk re-duction advice cautioning against heavy lifting (38). Thisstudy, however, found no evidence to suggest that partici-pation in activities of daily living that include intermittentheavy-load lifting need be avoided. Furthermore, a variedresponse to resistance exercise was observed for both in-tensities. This highlights the importance of an individualizedapproach to resistance exercise prescribed in accordancewith signs and symptoms of BCRL, as well as an individu-alized approach to the risk reduction advice given to breastcancer survivors.

In conclusion, the acute lymphatic response was similarirrespective of whether low- or heavy-load resistance exer-cise was undertaken in women with axillary node dissectionat risk for BCRL during adjuvant taxane-based chemother-apy. Future research needs to now investigate the longer-term response to regular heavy-load resistance exercise. Inthe interim, these findings challenge existing risk reductionadvice concerning avoidance of heavy lifting and suggestthat breast cancer survivors should be encouraged to par-ticipate in normal daily activities and to act accordingly ifchanges in sensations or BCRL symptoms are observed.

We gratefully acknowledge exercise physiologists ChristianLillelund for his input in the conception of the study and JesperChristensen for his assistance with the random allocation of partici-pants. Also thanks to staff at the Department of Clinical Physiologyand Nuclear Medicine at the Copenhagen University Hospital,Rigshospitalet, for excellent data collection and the CopenhagenCentre for Cancer and Health for help in recruitment. Lastly, thanksto the participants for dedicating time and energy and making thestudy possible.

This study was funded by the University Hospitals Centre for HealthResearch (UCSF), Copenhagen University Hospital, Rigshospitalet.The authors declare no conflict of interest. The results of the study arepresented clearly, honestly, and without fabrication, falsification, orinappropriate data manipulation and do not constitute endorsementby the American College of Sports Medicine.

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Paper IV

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1

Heavy-load resistance exercise in pre-diagnosis, physically inactive

women at risk of breast cancer-related lymphedema during

adjuvant chemotherapy: a randomized trial

Kira Bloomquist1, Lis Adamsen1, Sandra C Hayes2, Christian Lillelund1,

Christina Andersen1, Karl Bang Christensen3, Peter Oturai4, Bent

Ejlertsen5, Malgorzata K Tuxen6, Tom Møller1

University Hospitals Centre for Health Research (UCSF), Copenhagen University Hospital, Copenhagen, Denmark

Corresponding author: Kira Bloomquist

University Hospitals Centre for Health Research, UCSF

Copenhagen University Hospital

Blegdamsvej 9

2100 Copenhagen, Denmark

E-mail: [email protected]

Telephone: +45 35457362

1University Hospitals Centre for Health Research (UCSF), Copenhagen University

Hospital, Blegdamsvej 9, 2100 Copenhagen Ø, Denmark, (LA) + 45 35457338,

[email protected]; (CL) +45 35457335, [email protected]; (CA) +45

35457388, [email protected]; (TM) +4535457366,

[email protected]; 2Institute of Health and Biomedical Innovation, School of Public Health and Social

Work, Queensland University of Technology, Victoria Park Road, , Kelvin Grove,

4059, Queensland, Australia, +61 31389645, [email protected] 3Department of Public Health; Section of Biostatistics, University of Copenhagen,

Øster Farimagsgade 5, 1014 Copenhagen K, Denmark, +45 35327491,

[email protected]

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2

4Department of Clinical Physiology, Nuclear Medicine and PET, Copenhagen

University Hospital, Blegdamsvej 9, 2100 Copenhagen, Denmark,+45 3545 9665,

[email protected] 5DBCG, Afsnit 2501, Copenhagen University Hospital, Blegdamsvej 9, 2100

Copenhagen Ø, Denmark, +45 35253417, [email protected] 6Oncology department, Team MA, Herlev Hospital, Herlev Ringvej, 2730 Herlev,

Denmark, +45 35454090, [email protected]

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3

Heavy-load resistance exercise in pre-diagnosis physically inactive women at risk of

breast cancer-related lymphedema during adjuvant chemotherapy: a randomized trial

Abstract

Background

It is unclear whether participating in heavy-load resistance exercise is safe for breast

cancer survivors considered at risk of developing lymphedema. This study

prospectively evaluated changes in lymphedema outcomes following participation in

repeated exposure to heavy-load resistance exercise during adjuvant chemotherapy in

physically inactive women with breast cancer.

Material and Methods

This is a parallel group, randomized trial. Screened pre-diagnosis physically

inactive women receiving adjuvant chemotherapy for breast cancer (n=153)

participated in 12 weeks of 1) HIGH: supervised multimodal exercise

including heavy-load resistance exercise (85-90% 1 repetition maximum (RM),

three sets of 5-8 repetitions) or 2) LOW: walking supported by pedometer and

one-on-one consultations. Outcomes: swelling (bioimpedance spectroscopy, L-

Dex scores; dual energy X-ray absorptiometry, inter-arm volume % difference;

self-report, n %), lymphedema symptoms (0-10 rating scale), upper-extremity

strength (1 RM), and self-reported function and symptoms (EORTC breast

cancer-specific questionnaire (BR23)), assessed at baseline, 12 and 39 weeks.

Linear mixed models with a heterogeneous autoregressive (1) covariance

structure were used to evaluate changes over time between groups.

Equivalence was hypothesized for lymphedema outcomes, and was determined

using the principle of confidence interval inclusion.

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Results

Post-intervention equivalence between groups was found for L-Dex and self-reported

heaviness, tightness and swelling. Non-equivalence was determined for inter-arm

volume and pain, as deviations beyond equivalence margins indicated reductions

associated with participation in the HIGH intervention for these two outcomes.

Further, greater increases (p < 0.05) in upper-extremity strength were seen in the

HIGH group compared to LOW at all assessments, and within group reductions in

breast and arm symptoms were observed in the HIGH group at 6 and 12 weeks.

Conclusion

This study indicates that pre-diagnosis physically inactive women considered at risk

of lymphedema during adjuvant chemotherapy for breast cancer can benefit from

heavy-load resistance exercise without adversely influencing lymphedema outcomes.

Trial registration: ISRCTN24901641.

Keywords: arm swelling; breast cancer; strength training; rehabilitation

Word count:4,661

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Introduction

Breast cancer-related arm lymphedema (BCRL) is a chronic condition characterized

by swelling of the arm on the surgical side, experienced by almost a quarter of breast

cancer survivors and has adverse physical, social and psychological ramifications (1-

4). Since the pathophysiology of BCRL remains unclear, efforts to predict who will

develop BCRL are limited (5). Nonetheless, consistent evidence supports several risk

factors including more extensive surgery (mastectomy and axillary lymph node

dissection and greater number of lymph nodes removed), receipt of adjuvant

therapies (chemotherapy and radiotherapy) and lifestyle-related factors such as

obesity and physical inactivity (1).

Receipt of adjuvant chemotherapy for breast cancer is associated with

declines in physical activity (6). This in turn contributes to common increases in

body weight (7-10) characterized by no change or decline in muscle mass in the

presence of increased body fat (sarcopenic obesity) (7), and is adversely associated

with reductions in muscle strength and functional impairment (11, 12). Therefore,

interventions that thwart sarcopenic obesity are pertinent, with heavy-load resistance-

exercise considered an effective strategy. This is due to the dose-response

relationship that exists between resistance exercise and lean tissue, whereby heavier

loads have been shown to elicit greater gains in muscular size, structure and function

than with lower loads (13, 14).

However, there are anecdotal concerns that resistance exercise with heavy

loads may trigger the development of BCRL. While previous interventions have

demonstrated the safety of resistance exercise of low to moderate loads (60-80% of 1

repetition maximum (RM) or 8-20 RM) (15-18), only the acute response to heavy-

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load resistance exercise has been evaluated in those at risk of developing BCRL.

Specifically, a recent study found that the acute lymphatic response was similar after

a single bout of low-and heavy-load resistance exercise in at -risk women (n = 21)

(19). While providing important preliminary information, the safety of repeated

exposure to heavy-load resistance exercise has yet to be examined in this particular

cohort.

Therefore, we prospectively compared the effect of a supervised, multimodal

intervention including heavy-load resistance exercise (80-90% 1 RM or 5-8 RM)

with a home-based individual walking intervention in pre-diagnosis physically

inactive breast cancer survivors during adjuvant chemotherapy. A full report

detailing the results on aerobic capacity (the primary outcome), body composition

and quality of life can be viewed elsewhere (ISRCTN24901641). The primary

purpose of this manuscript is to report on the effect of the interventions on BCRL

and upper-extremity outcomes. We hypothesized that changes in BCRL outcomes

would be similar irrespective of intervention allocation. Further, we hypothesized

that participation in the multimodal intervention would yield significant increases in

upper-extremity muscular strength and breast cancer-specific functional and

symptom domains compared to the walking intervention.

Material and Methods

This study utilized a parallel group, randomized design (n=153; detailed description

of study design and methods have been previously reported) (20, 21). The study was

conducted at the University Hospitals Centre for Health Research, Copenhagen

University Hospital, Rigshospitalet. Written informed consent was provided by all

participants before inclusion to the study. The study was approved by the Danish

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Capital Regional Ethics Committee (H-1-2011-131) and the Danish Data Protection

Agency (2011-41-6349) and registered at Current Controlled Trials

(ISRCTN24901641).

Participants

Women referred to adjuvant chemotherapy for stage I-III breast cancer at the

oncology departments of The Copenhagen University Hospital, Rigshospitalet (RH)

and Herlev Hospital (HE) were screened for eligibility by nurses / physicians upon

initiation of chemotherapy. Women were eligible if they had a World Health

Organization performance status 0-1, and retrospectively rated their physical activity

levels three months prior to diagnosis as less than 150 minutes of regular, moderate-

intensity physical activity and / or 2 x 20 minutes of high-intensity exercise per week

(22). If initial criteria were met, women were then referred to the research team and

matched against exclusion criteria (diagnosed acute coronary heart syndrome within

the past six months, symptomatic heart disease, pathological echocardiogram,

contraindication for exercise noted in medical records, unable to read or understand

Danish). Participant flow in the study is presented in Figure 1.

Randomization

After successful completion of all baseline assessments (6-9 weeks post-surgery),

women were sequentially numbered and stratified by age (<48/48+ years) and

hospital (RH/HE). Intervention allocation (1:1) was determined by a computerized,

random number generated at the Copenhagen Trial Unit, which is an external clinical

research unit.

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Guidelines regarding BCRL

Participants were asked if they had received treatment for BCRL at the baseline

assessment, either preventatively or as a means to reduce swelling after a diagnosis

of BCRL, and were given verbal and written information, highlighting current

evidence-based risk factors for developing BCRL (e.g. lymph node removal, BMI,

physical inactivity). Participants were encouraged to contact study personnel if signs

or symptoms of BCRL development (e.g. sensations of heaviness/tightness or visible

signs of swelling) presented or exacerbation of an existing BCRL occurred during

the study period. Either scenario would then instigate referral to a lymphedema

therapist for evaluation and treatment.

Interventions

HIGH

Participants randomized to the HIGH group participated in a twelve-week, group-

based exercise program, supervised by a cancer nurse specialist and a physical

therapist / exercise physiologist. The first six weeks consisted of a previously

described exercise program ‘Body and Cancer’ (20, 23, 24), which entailed

multimodal sessions including low-intensity and high-intensity components. The

following six weeks consisted of an ‘All sport’ exercise program focusing on high-

intensity components combined with other aerobic activities performed at moderate

to high intensities. (Table 1) (20). The high-intensity component included an aerobic-

based warm-up followed by resistance exercise and 15-30 minutes of cardiovascular

interval training on stationary bikes with peak loads equivalent to 85-95% maximal

heart rate. The resistance exercise program comprised of six machine-based

exercises (Technogym®, Gamettola, Italy) targeting major muscle groups of the body

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(chest press, latissimus pull down, abdominal crunch, back extension, leg press and

knee extension). Resistance exercise loads were based on a 1 RM strength test for

each exercise. During the first week participants were instructed to lift loads

corresponding to 2-3 sets of 8-12 repetitions at 70% 1 RM, progressing to 80% 1 RM

in week two. From week three forward, loads lifted corresponded to 3 sets of 5-8

repetitions at 80-90% 1 RM. To ensure progression, resistance exercise programs

were adjusted every third week based on new 1 RM testing.

Pre-exercise screening was performed prior to all high-intensity exercise

sessions, with subsequent modified exercise intensity or omission from high-

intensity activities that day if criteria were not met (e.g., resting heart rate >100 beats

per minute, temp > 38o C) (20, 23). If participants developed signs of BCRL or

experienced exacerbations of an existing BCRL, they were instructed to refrain from

resistance exercise targeting the upper-extremities or to decrease loads, and were

referred to a lymphedema therapist.

LOW

The LOW intervention involved an individualized, home-based walking program

supported by a pedometer and one-on-one consultations with a cancer nurse

specialist or physical therapist (Table 1). Participants were issued an Omron Walking

Style Pro pedometer at baseline, and were encouraged to progressively increase steps

and ultimately to achieve 10,000 steps per day. Consultations were regularly held to

discuss daily walking targets and barriers and motivators for achieving these targets.

Beyond walking, participants were encouraged to exercise and to integrate physical

activity into activities of daily living.

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Both interventions provided health promotion counselling (20) including

clinical advice concerning symptom management and feedback regarding

physiological outcomes.

Outcomes

BCRL was objectively assessed (inter-arm volume % difference and L-Dex) at

baseline, 12 and 39 weeks, by medical technicians at the Department of Clinical

Physiology and Nuclear Medicine, Rigshospitalet. Muscle strength and self-reported

outcomes were obtained by research assistants at the University Hospitals Centre for

Health Research, Rigshospitalet at baseline, 6, 12 and 39 weeks.

Inter-arm volume % difference

Arm volume was obtained using Dual energy X-ray absorptiometry (DXA) (Lunar

Prodigy Advanced Scanner, GE Healthcare, Madison, WI). DXA provides a

sensitive measure of tissue composition using a three-compartment model (25, 26).

Lying supine on the scan-table with arms slightly abducted and hands in a mid-prone

position, total body scans were performed. Scans were automatically point typed and

analyzed using encore version 16, GE Healthcare Lunar software. From the total

body scans, the measured weight of fat, lean mass and bone mineral content of both

arms were identified and converted into estimated arm volumes using previously

derived densities (fat - 0.9 g/ml, lean mass -1.1g/ml, bone mineral content - 1.85

g/ml)) with the region of interest extending from the gleno-humeral joint to the

finger tips (25, 26). Inter-arm volume % differences (at-risk arm minus unaffected

arm/unaffected arm * 100) were then calculated for each participant. To ensure

accuracy, participants were scanned fasting at the same time of day (mornings) at all

assessments.

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L-Dex

Bioimpedance spectroscopy (BIS) (SFB7, Impedimed, Brisbane, Australia) was

performed immediately after the DXA scans. This measurement method directly

measures and compares the impedance of extracellular fluid in the upper-extremities

to electrical currents at a range of frequencies according to the manufacturer’s

software (27). Participants were positioned in supine with arms and legs slightly

abducted with palms facing down. Using the principle of equipotentials, four single-

tab electrodes were placed in a tetrapolar arrangement. Measurement electrodes were

placed on the dorsum of the wrist midway between the styloid processes. Current

drive electrodes were placed five centimeters distally on the dorsal side over the third

metacarpal of the hand, and midway on the third metatarsal on the dorsum of the foot

(28). The ratio of impedance (at R0) between the at-risk and non-affected arm was

calculated and converted into an L-Dex score taking arm dominance into account

(29). BIS data were consecutively obtained from participant 71 forward.

Self-reported swelling

Participants were asked if they had observed a difference in size between their

surgical-and non-surgical side within the last week (dichotomous scale- yes/no). If

they answered yes, they were then asked to report where (fingers, hand, forearm,

upper arm, breast, torso). For the purpose of binary analysis, categories were divided

into “extremity” (fingers, hand, forearm, upper arm) and “body” (breast, torso).

Self-reported BCRL symptoms

The severity of lymphedema symptoms on the surgical side was monitored using a

numeric rating scale (NRS)(30). Participants rated perceptions of swelling,

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heaviness, pain and tightness within the last week on a scale from 0 (no discomfort)

to 10 (very severe discomfort)(31).

Upper-extremity muscular strength

To assess maximal strength of the upper extremity, the 1 RM strength test (32) was

performed using the chest press exercise. The 1 RM is the maximum amount of

weight that can be lifted for one repetition while maintaining proper technique. Prior

to the 1 RM attempt, a warm-up consisting of 8-10 repetitions using a low weight

ensuring no muscle fatigue occurred was performed. Hereafter, load was increased

based on ease of performance, with one repetition lifted of each load, until the

participant was unable to lift a respective load.

Breast cancer-specific functional and symptom domains

The 23 item European Organization for Research and Treatment of Cancer (EORTC)

breast cancer module (BR23)(33), version 3.0, was used to assess breast cancer-

specific quality of life issues. This validated breast cancer-specific module includes

four functional scales (body image, sexual functioning, sexual enjoyment, future

perspective), as well as four symptom specific subscales (systemic therapy side

effects, breast symptoms, arm symptoms, upset by hair loss). Each item is scored on

a four point Likert scale from “not at all” to “very much”. The raw scores were

summed and converted to a score out of 100, with higher levels of functioning

represented by higher functional scores and worse symptoms represented by higher

symptom scores (33, 34).

Blinding

Inherent to exercise studies, patients, nurses and physical therapist delivering the

interventions were aware of the allocated arm. However, all data collection and

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subsequent data entry were performed blinded to group allocation by study assessors.

Further, all data analyses were performed with no knowledge of group allocation by

a statistician with no other affiliation to the study.

Statistical Analysis

Descriptive statistics included means ± SD for normally distributed variables or

median with interquartile range (IQR) for continuous variables. Categorical variables

as well as BCRL point prevalence defined as L-Dex >10, inter-arm volume

difference >5%, self-reported observation of swelling, respectively are presented as

counts (percentages). Intention-to-treat analyses were performed using linear mixed

models with a heterogeneous autoregressive (1) covariance structure to estimate

changes over time in each group. An exchangeable correlation structure was used to

model the within-subject correlation of repeated measurements over time and across

interventions. This incorporates all available data including participants with

incomplete data. Also, effect sizes were calculated for muscular strength (35). A

two-sided significance level was set at 0.05 for outcomes where superiority was

hypothesized (muscular strength and breast cancer-specific functional and symptom

domains).

A priori, clinically relevant equivalence margins were chosen for BCRL

outcomes. If the interval between the upper- and lower- confidence limits was within

the predetermined equivalence margin, equivalence between interventions was

declared (36). An equivalence margin of ±3.0% was used for inter-arm volume %

differences based on findings from Stout et al., (37) that volume increases of >3%

from pre-operative measures were indicative of sub-clinical BCRL. For L-Dex, the

margin of equivalence was set at ±5.0 units based on normative data indicating that

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L-Dex scores fluctuate between 9-11 units (29). For lymphedema symptom severity

an equivalence margin was set at ±1.0 points. This threshold was based on data that

suggest a 2 point or 30% change to be clinically meaningful for pain (30). The

principle of confidence interval inclusion (38) was used to calculate two one-sided

upper- and lower-95% confidence limits for L-Dex, inter-arm volume % differences,

and BCRL symptom outcomes (reported as 90% confidence limits). A per-protocol

analysis was performed to determine equivalence of BCRL outcomes of participants

with an adherence rate >65% to the HIGH intervention (n = 33). Means and 90% CI

were calculated and compared with the predetermined equivalence margins.

Analyses were conducted using Statistical Analysis Software (SAS) version 9.4.

Results

Between January 2014 and July 2016, 153 of 391 (39%) eligible women receiving

adjuvant chemotherapy for breast cancer were recruited (Figure 1). Baseline

characteristics were balanced between the two intervention groups (Table 2).

For participants with and without L-Dex data, baseline characteristics were balanced

with the exception of chemotherapy regime, as more participants with L-Dex data

had received paclitaxel based chemotherapy (13 (20.3%) vs. 6 (6.7%, respectively).

Further, differences were seen in the mean BMI of participants with and without

inter-arm volume data as the body dimensions of some participants exceeded the

DXA scan area (24.3 ± 3.6 with DXA vs. 31.2 ± 5.2 without DXA).

Retention, adherence and adverse events

Outcome data were available for 130 participants (85%) at 12-weeks post-

intervention, and for 121 (79%) at the 39 week follow-up (Figure 1). On average,

participants in the HIGH group attended 66% (±18) of the planned exercise sessions.

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Four women never partook in the intervention and an additional six withdrew shortly

after initiation of the program. A detailed description of reasons for non-attendance

can be found elsewhere (in submission). Adherence to resistance exercise

prescription of the upper-extremity corresponded to a median load of 10 RM during

the first two weeks. From week three forward (heavy-load period), loads

corresponded to 7 RM. Comparatively loads lifted for the leg press were 14 RM and

8 RM, respectively.

No exercise-related injuries were reported. Six participants (8%) in the HIGH

and five participants (6%) in the LOW group developed swelling during the 12-week

intervention and were referred to lymphedema therapists for evaluation and

treatment. Just one of the women in the HIGH group reduced loads (10-15 RM),

whereas the other five continued lifting loads corresponding to 5-8 RM. At 39

weeks, seven of these participants had received treatment for BCRL by a

lymphedema therapist following the intervention, while three had not, and one was

lost-to follow-up.

Lymphedema

Point prevalence: While point prevalence of BCRL varied depending on the method

of assessment (Table 3), it was similar between the HIGH and LOW group at all time

points, for any given method of assessment (Table 3).

Self-reported diagnosis of BCRL at baseline: Five participants (3.3%) reported at

baseline that they were receiving treatment for a diagnosed BCRL, all of whom also

reported observations of size difference between sides within the last week (Table 3).

One of these women had an L-Dex >10, accounting for one of two point prevalent

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cases identified by BIS (Table 3). No L-Dex was available for three participants. In

regard to inter-arm volume, no DXA data were available for two women (body

dimensions exceeding scan area), and two others had swelling in the torso only

(DXA not able to detect). One of the five participants was in the HIGH group. This

woman continued treatment by a lymphedema therapist throughout the twelve-week

intervention and undertook the resistance exercise protocol without need for

modification (e.g. less load). At twelve weeks she reported no observations of

swelling along with reductions in symptoms. No DXA or BIS data were available.

Inter-arm volume % difference: Non-equivalence was observed at all time points for

inter-arm volume % differences with deviations exceeding equivalence margins

favoring the HIGH group (Table 4). These observations were consistent with

findings from the per-protocol analysis (Table 5).

L-Dex: The mean difference in L-Dex scores between the HIGH and LOW group

and associated two-sided 90% CIs were contained within the predetermined

equivalence margin of ±5.0 units at both 12 and 39 weeks indicating equivalence

between groups (Table 4). Equivalence to the predetermined equivalence margin in

the per-protocol analysis at 12 weeks was also observed (Table 5). However at the 39

week follow-up, the upper CI exceeded the predetermined margin of equivalence

(Table 5).

BCRL symptoms: Equivalence between groups was found in all symptoms except for

pain at the 12 week follow-up, and tightness and pain at the 39 week follow-up, with

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all findings favoring reductions for those in the HIGH group (Table 4). Results of the

per-protocol analysis also indicated equivalence for heaviness and swelling post-

intervention and at the 39 week follow-up, as well as pain post-intervention (Table

5). However, non-equivalence was found for pain at the 39 week follow-up as upper

CI’s exceed the equivalence margin. Further, equivalence could not be determined

for tightness, as lower CI’s exceeded the equivalence margin at both follow-up time

points, as well the mean change at the 39 week follow-up.

Upper-extremity muscular strength

A significant change in maximal upper-extremity strength was observed for

participants in the HIGH group at all follow-up assessments (Table 6). At 6- and 12-

week follow-up, these strength increases were significantly greater compared to

those in the LOW group and corresponded to effect sizes of 0.55 (95% CI 0.40 –

0.75), 0.55 (0.35 – 0.70) and 0.35 (0.15 – 0.55) at the 6, 12 and 39 weeks follow-up,

respectively.

Breast cancer-specific functional and symptom domains

No between group differences were observed for any subscale score of the EORTC-

BR23 at all assessments (Table 4 and supplemental material). Nonetheless, both

groups reported declines in breast symptoms at 6 and 12 weeks follow-up and arm

symptoms at 6 weeks follow-up, while reductions in arm symptom at 12 weeks

follow-up was only seen in the HIGH group.

Discussion

This is the first study to prospectively evaluate the safety of repeated exposure to

heavy-load resistance exercise in breast cancer survivors at risk for BCRL. We found

no evidence suggesting that participating in a twelve-week multimodal exercise

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intervention including heavy-load resistance exercise during chemotherapy increased

risk of developing BCRL. In line with the hypothesis, we found similar point

prevalent cases of BCRL between groups, as well as similar between group L-Dex

scores and perceptions of heaviness, swelling and tightness post-intervention.

Though equivalence was not demonstrated in inter-arm volume % differences or

self-reported pain, the negative deviations indicated reductions of these outcomes,

favoring the HIGH group. Notably, per-protocol analysis of HIGH participants with

>65% adherence consistently supported equivalence to- or reductions beyond the

predetermined equivalence margins, adding strength to the findings.

This work extends the results of previous research finding a similar acute

lymphatic response to one bout of low-and heavy-load resistance exercise (19), to

repeated exposure of resistance exercise with heavy loads. Further, our results are in

agreement with findings of Cormie et al. (31, 39) who demonstrated the safety of

heavy-load (75-85% of 1 RM using 6-10 RM) resistance exercise in breast cancer

survivors with stable BCRL. As such, these results add to a growing and consistent

evidence base which suggests that exercise is safe for those with or at-risk of

developing lymphedema (15-18), and includes participation in heavy-load resistance

exercise. Notably, the findings contributed to the broader literature by this work are

particularly relevant for the majority of breast cancer survivor who receive

chemotherapy as taxane-based chemotherapy is considered standard first line

treatment (40, 41), with generalized edema and ensuing arm swelling as a known

side-effect of this cytostatic agent (42).

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No between group differences in breast and arm symptoms were found

between interventions, consistent with results from two previous studies (39, 43).

Kilbreath et al. (n = 160) found no difference in arm and breast symptoms between

women at risk of BCRL after eight weeks of resistance exercise using loads

corresponding to 8-15 RM, commencing 4-6 weeks post-surgery, and a control

group (43). Similarly, in women with stable BCRL, Cormie et al. (n =62) found no

difference in arm symptoms between two resistance exercise groups (heavy and low

load) and a control group (39). Notably however, though no differences between

groups were found, clinically relevant within group reductions in breast and arm

symptoms were found in the HIGH group (44) at both 6- and 12 weeks. These

findings are consistent with the BCRL results from the present study, adding strength

to the findings.

Participation in HIGH significantly improved upper-extremity strength

compared to the LOW intervention, with an effect size of 0.55 (95% CI 0.35-0.70)

post-intervention. These data are consistent with pooled estimates from a systematic

review (16) that included fifteen randomized controlled studies evaluating

populations with stable BCRL or at risk for developing BCRL. Findings from the

meta-analysis showed that participation in resistance exercise significantly increased

muscular strength compared to controls (effect size 0.57 (95% CI 0.37-0.76).

Further, upper-extremity strength increases corresponded to 17.24%, 13.33%, and

6.67% at 6, 12, and 39 weeks, respectively, for those in the HIGH group, compared

to a 3.33%, 3.33% and 3.44% increases in the LOW group. These are relevant

findings as upper-extremity strength in breast cancer survivors (without intervention)

has been found to be 12-16% lower compared to healthy women (45). As such, the

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present study indicates that participation in heavy-load resistance exercise during

chemotherapy can mitigate declines in muscle strength, of importance for

recreational and daily living activities (46). Future studies should therefore explore

whether additional benefits can be gained from resistance exercise with heavier loads

during chemotherapy, as published results suggest superior efficacy in decreasing

fatigue (47) and rate of bone loss (48) and increasing lean body mass (49).

At 39 weeks follow-up, we found that the longer term effect of the LOW and

HIGH intervention was similar between groups or indicated reductions favoring the

HIGH group for all outcomes. These findings were consistent with the per-protocol

analysis of the HIGH group, with the exception of L-Dex and pain as upper CI’s

indicated a slight increase beyond the predetermined equivalence margin. However,

in general, care should be taken when interpreting the 39 week follow-up results as

no data regarding upper-extremity resistance exercise behavior was collected post-

intervention, and is a limitation of this study. Consequently, we cannot determine

whether effects seen at 39 weeks were a result of / or decline in resistance exercise or

other unknown factors.

Additional limitations should be considered when interpreting findings. First,

usual care in Denmark includes municipality lead rehabilitation programs and was

therefore available for all participants irrespective of group allocation. These

programs are generally offered one to two times per week and consist of breast

cancer-specific range of motion exercises, instruction in self-massage, as well as

aerobic and / or resistance exercise at low to moderate intensities. It is thus likely that

a proportion of those in the LOW group, also participated in resistance-based

exercise at low to moderate loads during the intervention period. While there exists

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uncertainty as to the extent of this potential bias, the impact on findings would likely

dilute differences between interventions. In addition, though groups were statistically

balanced at baseline, it should be noted that more participants in the LOW group had

ALND and had been diagnosed with BCRL at baseline potentially swaying the

results in favor of the HIGH group. Further, in all 28% of the sample are missing

DXA inter-arm volume data due to body dimensions exceeding the scanning area,

why caution in generalizing these findings to obese women is required. Future

studies should be aware of this limitation and perform separate arm scans (50) as an

alternative for these individuals. Also, to strengthen BCRL data, extracellular fluid

measured by BIS was added to the test battery from participant 71 forward (54% of

the sample). Therefore, complete data was not available for these two outcomes.

Nonetheless, the comprehensive assessment of BCRL used in this study (that is, two

objective methods of assessment, alongside self-report) ensured that each participant

contributed 100% data for at least one outcome measure and adds strength to these

findings.

Strengths of the study include the randomized design as well as blinded

assessments and analyses. Further, intention-to-treat analyses were performed for all

outcomes as well as per-protocol analyses of HIGH participants with adherence rates

> 65% for BCRL outcomes, and consistency in findings was observed. In addition,

this study targeted breast cancer survivors who were physically inactive before

diagnosis. This is important as fear of lymphedema has been identified as a barrier

for physical activity and especially vigorous or strength activities (51). This, in turn

may lead to avoidance and non-adoption of regular physical activity and thereby

further increasing risk of BCRL for this significant group (1). Also, attitude towards

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exercise can be transformed from having no priority to being highly prioritized if

support to adopt exercise is received during adjuvant chemotherapy (52). This is of

potential importance for long term exercise behavioral change, ultimately leading to

better health outcomes (53, 54). Finally, the equivalence design was considered the

most appropriate for testing our hypothesis in regard to BCRL outcomes. The value

and impact of establishing equivalence depends on how well the equivalence margin

can be justified in terms of relevant evidence and clinical judgement. Equivalence

margins ideally represent the maximum clinically acceptable difference that one is

willing to accept in return for the secondary benefits of a new therapy (36), whereas

a narrower equivalence margin makes it more difficult to establish equivalence (36).

A more conservative equivalence margin for all outcomes was purposely set in order

to ensure credibility of results. Arguably though, this may have created confidence

limits with an unnecessarily narrow interval rendering conclusions of non-

equivalence.

In conclusion, findings from this study suggest that breast cancer survivors

who are physically inactive before diagnosis benefit from and can safely participate

in a multimodal intervention that includes supervised, heavy-load resistance exercise

of the upper-extremities during adjuvant taxane-based chemotherapy. Importantly, as

this study targeted breast cancer survivors with multiple risk factors for developing

BCRL (surgery, physically inactive, overweight, taxane-based chemotherapy),

applicability extends to those considered at additional risk for developing BCRL. As

such, these findings can be used to encourage adoption of exercise including heavy-

load resistance exercise during and following breast cancer treatment.

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Funding

This study was one of several studies conducted under The Center for Integrated

Rehabilitation of Cancer Patients (CIRE), Copenhagen, Denmark. CIRE was

established and supported by the Danish Cancer Society and the Novo Nordic

Foundation. The study also received funding from Trygfonden Denmark under Grant

number 7-12-0401.

Disclosure of interest

The authors report no conflict of interest.

Acknowledgements

We greatly thank the staff at the Department of Clinical Physiology and Nuclear

Medicine at the Copenhagen University Hospital, Rigshospitalet for collaboration in

data collection, and the participants for their dedication to the study.

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Captions for Figures

Figure 1. Flow of participants from recruitment and through the trial

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Table 1. Overview of HIGH and LOW interventions

HIGH intervention

Monday Tuesday Wednesday Thursday Friday

Part I:’Body and Cancer’ 6 weeks, 9 h/week

Aerobic and resistance

exercise (1.5 h)

Relaxation (0.5 h)

Swedish massage (0.5 h)

Body awareness (1.5 h)

Relaxation (0.5 h)

Aerobic and resistance

exercise (2 h)

Relaxation (0.5 h)

Aerobic and resistance

exercise (1.5 h)

Relaxation (0.5 h)

Swedish massage (0.5 h)

Part II: ‘All-sport’ 6 weeks, 6 h/week

Aerobic and resistance

exercise and e.g.

ballgames, dancing (2 h)

Aerobic and resistance

exercise and e.g.

ballgames, dancing (2 h)

Aerobic and resistance

exercise and e.g. ballgames,

dancing (2 h)

LOW intervention

Week 1 Week 2 Week 4 Week 6 Week 9 Week 12

Pedometer

consultation

Pedometer

consultation

Pedometer

consultation

Pedometer

consultation

Pedometer

consultation

Pedometer

consultation

Both interventions

Baseline Week 6 Week 12 Week 39

Health promotion counselling Health promotion counselling Health promotion counselling Health promotion counselling

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Characteristics Total (n = 153) HIGH (n = 75) LOW (n = 78)

Age (years), mean ± SD 51.7 ± 9.4 51.5 ± 9.6 52.0 ± 9.3

BMI (kg/m2), mean ± SD 26.1 ± 5.1 26.2 ± 5.3 26.0 ± 4.9

Cancer stage, n (%)

Stage 1

Stage 2

Stage 3

56 (36.6%)

81 (52.9%)

16 (10.5%)

31 (41.3%)

36 (48.0%)

8 (10.7%)

25 (31.1%)

45 (57.7%)

8 (10.3%)

Breast surgery, n (%)

Lumpectomy

Mastectomy

Mastectomy plus expander

90 (58.8%)

56 (36.6%)

7 (4.6%)

47 (62.7%)

26 (34.7%)

2 (2.7%)

43 (55.1%)

30 (38.5%)

5 (6.4%)

Axillary surgery, n (%)

Axillary lymph node dissection

Sentinel node biopsy

61 (39.9%)

92 (60.1%)

26 (34.7%)

49 (65.3%)

35 (44.9%)

43 (55.1%)

Nodes removed, median (IQR) 3 (2-17) 3 (1-15) 5 (2-19)

Surgery on dominant side*, n (%) 76 (49.7%) 39 (52.0%) 37 (47.4%)

No. of seroma drainages, median (IQR) 1 (0-5) 1 (0-5) 1 (0-5)

Chemotherapy, n (%)

3-wkly CE x 3 -> 3 wkly docetaxel x 3

3-wkly CE x 3 -> 1 wkly paclitaxel x 9

Other

130 (85.0%)

19 (12.4%)

4 (2.6%)

66 (86.7%)

8 (10.7%)

1 (1.3%)

64 (82.1%)

11 (14.1%)

3 (3.9%)

Observations of swelling**, n (%)

Extremity (hand, underarm, overarm)

Body (breast, torso)

Both (body & extremity)

5 (3.3%)

31 (20.5%)

11 (7.3%)

2 (2.7%)

14 (18.9%)

3 (4.1%)

3 (3.9%)

17 (22.1%)

8 (10.4%)

Treatment related to lymphedema**, n (%)

Preventatively

Existing lymphedema

4 (2.6%)

5 (3.3%)

1 (1.4%)

1 (1.4%)

3 (3.9%)

4 (5.2%)

Symptom subscales EORTC-BR23

Arm symptoms, mean ± SD

Breast symptoms, mean ± SD

16.2±19.0

18.9±16.1

15.6±20.1

18.6±16.4

16.8±18.0

19.2±16.0

L-Dexa, mean ± SD -0.3±5.1 -0.6±3.6 0.1±6.2

Table 2. Participant characteristics at baseline

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Volume % differenceb, mean ± SD 1.3±19.8 0.6 ±19.7 1.9±20.0

Upper-extremity strength (RM)c, mean ± SD 29.4±8.3 29.0±8.1 29.8±8.

Not included *n = 4 missing; **n = 2 missing; a n=73 (n = 70 bioimpedance spectroscopy not available, n = 1 missing, n = 2 bilateral axillary surgery); b n =35 (n = 5 bilateral axillary surgery, n = 30 exceeded DXA scan area); c n = 15 (n = 14 post-surgery restrictions, n =1 precautionary due to arm swelling) Abbreviations BMI, body mass index; SD, standard deviation; CE, cyclophosphamide & epirubicin; pctl, percentile/IQR, interquartile range

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Baseline 12 weeks 39 weeks

L-Dex > 10 a n n n

HIGH

LOW

39

41

0 (0.0%)

2 (4.9%)

33

31

3 (9.1%)

2 (6.5%)

41

34

4 (9.8%)

3 (8.8%)

Inter-arm volume % difference > 5% b

HIGH

LOW

55

63

15 (27.3%)

15 (23.8%)

45

51

14 (31.1%)

13 (25.5%)

50

49

12 (24.0%)

13 (26.5%)

Observed difference in size between sides within the last week c

HIGH

LOW

74

77

19 (25.7%)

28 (36.4%)

62

63

18 (29.0%)

13 (20.6%)

62

59

21 (33.9%)

22 (37.3%)

Based on all available data for each outcome.a Maximum n = 81 due to bilateral axillary surgery (n =2) and BIS not available (n = 70). At 39 weeks BIS was available for twelve of these particicpants and included in the analysis ; b Maximum n = 148 due to bilateral axillary surgery (n = 5), n = 30, 28, 14 exceeded DXA scan area, respectively at baseline, 12 and 39 weeks and were therefore not included in the analysis); c Of the participants that observed swelling at: baseline n = 31 (66%), 12 weeks n = 8 (25.8%), 39 weeks n = 17 (39.5%) reported swelling located to the body (breast , torso) only

Table 3. Lymphedema point prevalence. Number of participants (%)

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Table 4. Equivalence between groups for BCRL outcomes

Mean difference* Equivalence 90% CI

L-Dex (±5.0)a (n =81)** n

12 weeks 64 0.4 -2.5 to 3.2

39 weeks 63 0.7 -2.2 to 3.6

Inter-arm volume % difference (±3.0)a (n =148)**

12 weeksǂ 86 -3.5 -17.3 to 10.3b

39 weeksǂ 83 -1.7 -7.7 to 4.3b

Pain (±1.0)a

(n =153)**

12 weeks 124 -0.7 -1.3 to 0b

39 weeks 121 -0.8 -1.5 to -0.1b

Heaviness (±1.0)a (n =153)**

12 weeks 124 -0.2 -0.6 to 0.2

39 weeks 121 0.0 -0.7 to 0.6

Tightness (±1.0)a

(n =153)**

12 weeks 124 -0.1 -0.8 to 0.6

39 weeks 121 -1.0 -1.8 to 0.2b

Swelling (±1.0)a

(n =153)**

12 weeks 124 0.2 -0.4 to 0.8

39 weeks 120 0.0 -0.8 to 0.7

*Mean difference between groups with HIGH as comparator (HIGH minus LOW); **Maximum n; ǂn = 38 and 30 not included at 12 and 39 weeks respectively, due to body dimension exceeding the DXA scan area; aPre-determined equivalence margin; Bold = equivalence not demonstrated; bnegative deviation reflecting reductions beyond the equivalence margin favoring the HIGH group

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Variable Baseline 12 weeks 39 weeks 12 weeks - baseline 39 weeks-baseline

Mean (SD) Mean (SD) Mean (SD) n Δ (90 % CI) n Δ (90 % CI)

L-Dex (±5.0)a -0.8 (3.3) 0.9 (6.6) 1.5 (5.3) 21* 1.7 (-0.8 to 4.2) 21* 3.2 (0.9 to 5.5)c

Inter-arm volume

% difference (±3.0)a

5.3 (23.0) 4.3 (27.2) 0.6 (7.4) 21** -3.1 (-19.5 to 13.4)b 26** -5.0 (-12.8 to 2.9)b

Pain (±1.0)a 1.0 (1.7) 0.6 (1.2) 1.4 (2.5) 32 -0.4 (-0.9 to 0.1) 33 0.4 (-0.4 to 1.2)c

Heaviness (±1.0)a 0.5 (1.3) 0.3 (1.1) 0.9 (1.7) 32 -0.2 (-0.4 to 0.1) 33 0.4 (0.0 to 0.8)

Tightness (±1.0)a 1.6 (2.4) 0.8 (1.9) 0.4 (0.8) 32 -0.9 (-1.5 to -0.2)b 33 -1.2 (-2.0 to -0.5)b

Swelling (±1.0)a 1.1 (2.0) 1.0 (1.8) 1.0 (1.8) 32 -0.1 (-0.7 to 0.6) 33 -0.1 (-0.6 to 0.5)

a Pre-determined equivalence margin; *maximum n = 21; Bold = equivalence not demonstrated;**maximum n = 32; b negative deviation reflecting reductions beyond the equivalence margin; c positive deviation reflecting increases beyond the equivalence

Table 5. Per-protocol equivalence of BCRL outcomes in participants with >65% adherence to HIGH (n = 33)

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  Δ 6 weeks‐baseline  Δ 12 weeks‐baseline  Δ 39 weeks‐baseline 

Variable  n Mean Δ (95% CI) 

Group difference (95% CI)  n 

Mean Δ (95% CI) 

Group difference (95% CI)  n 

Mean Δ (95% CI) 

Group difference (95% CI) 

Muscular strength 1 RM (kg)* Chest press     HIGH    LOW  

 58 51 

 5 (3 to 6) 1 (‐1 to 2) 

 4 (2 to 6) 

 56 55 

 4 (3 to 6) 1 (0 to 3) 

 3 (1 to 5) 

 50 44 

 3 (1 to 5) 1 (‐1 to 3) 

 2 (0 to 5) 

EORTC QLQ‐BR23 scores** Body Image HIGH  LOW  

 62 61 

 2 (‐3 to 7) ‐1 (‐6 to 3) 

 4 (‐3 to 10) 

 60 62 

 ‐3 (‐9 to 2) ‐6 (‐11 to ‐1) 

 2 (‐5 to 10) 

 61 56 

 7 (2 to 11)a 

6 (1 to 11)a 

 1 (‐6 to 8) 

Systemic therapy ǂ HIGH  LOW  

 63 62 

 5 (1 to 10)a 

4 (‐1 to 9)  

1 (‐6 to 8) 

 61 65 

 7 (2 to 12)a 

9 (4 to 14)a  

‐2 (‐9 to 6) 

 61 57 

 ‐19 (‐23 to ‐15)b 

‐20 (‐24 to ‐16)c  

1 (‐5 to 7) 

Breast symptoms HIGH LOW  

 62 62 

 ‐6 (‐9 to ‐2)a 

‐7 (10 to ‐3)a 

 1 (‐4 to 6) 

 60 64 

 ‐11 (‐15 to ‐7)b 

‐9 (‐12 to ‐5)a 

 ‐2 (‐8 to 3) 

 59 55 

 ‐4 (‐9 to 1) 1 (‐4 to 6) 

 ‐4 (‐12 to 

3) Arm symptoms HIGH  LOW  

 62 62 

 ‐4 (‐8 to 0)a 

‐5 (‐10 to ‐1)a 

 1 (‐5 to 7) 

 60 65 

 ‐6 (‐10 to ‐1)a 

‐4 (‐8 to 1) 

 ‐2  (‐8 to 4) 

 59 56 

 ‐1 (‐6 to 4) 3 (‐2 to 9) 

 ‐4 (‐12 to 

3) 

 

 

 

 

Abbreviations: CI, confidence interval; Bold = statistical difference (p <0.05); *No upper-extremity strength measures on one participant (LOW) at baseline due to visible and untreated swelling. No upper-extremity strength assessment at subsequent data collections as the participant was receiving treatment for lymphedema. Three participants (2 HIGH, 1 LOW) were not assessed for upper-extremity strength at 6, 12 and 39 weeks, as a precautionary measure due to swelling or because participants refused. An additional participant (HIGH) received treatment for lymphedema at 12 and 39 weeks and was therefore not tested; **Higher functional scores (body image) indicate higher levels of functioning, lower symptom scores (systemic therapy, arm and breast symptoms) indicate a reduction in symptoms; ǂ

Perceived treatment burden; a, b, c Subjective significance of changes from baseline in terms of a “small”, b “moderate”, c “large” (Osoba, 1998)

Table 6. Changes in upper-extremity strength and breast cancer specific functional and symptom domains

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6 weeks-baseline 12 weeks-baseline 39 weeks-baseline*

Variable

n

Mean

(95% CI)

Group difference

(95% CI) n

Mean

(95% CI)

Group difference

(95% CI) n

Mean

(95% CI)

Group difference

(95% CI)

Future perspective

HIGH 62 6.(-1 to 13) 5 (-5 to 15)

60 6 (-2 to 13) 8 (-2 to 19)

61 8 (0 to 16) 6 (-5 to 17)

LOW 61 0 (-6 to 7) 62 -3 (-10 to 5) 55 2 (-6 to 10)

Sexual functioning

HIGH 61 0 (-5 to 4) 1 (-5 to 8)

58 -1 (-6 to 4) 3 (-4 to 11)

58 8 (3 to 13) 2 (-5 to 10)

LOW 62 -2 (-6 to 3) 65 -5 (-10 to 0) 57 6 (1 to 11)

Sexual enjoyment

HIGH 17 -5 (-16 to 6) -4 (-20 to 11)

16 2 (-11 to 14) 13 (-3 to 29)

20 1 (-13 to 15) -4 (-23 to 14)

LOW 20 -1 (-11 to 9) 22 -12 (-22 to -1) 25 5 (-7 to 18)

Upset by hair loss

HIGH 30 -4 (-8 to 0) 1 (-5 to 7)

20 -6 (-10 to -1) -2 (-8 to 4)

*

LOW 28 -6 (-10 to -1) 21 -4 (-8 to 1)

* Upset by hair loss not obtained at 39 weeks.  

Supplementary table. Changes in breast cancer specific functional and symptom domains (EORTC‐BR23)

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Appendix B: Co-authorship declarations

 

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Appendix C: Study 1-Telephone interview guide

 

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Telefon interview/spørgeskema

Nej, har ikke lyst til at deltage Ja, telefon aftale tid og dag___________________

OPLYSNINGER OM DIG SELV

1. Alder____________

2. Hvor høje er du (cm)? __________ Hvor meget vejer du (kg)?______________

3. Hvad er din ægteskabelige status? (Sæt kun et kryds)

Samboende 1

Lever i parforhold 2

Gift 3

Single 4

Enke 5

Separeret/fraskilt 6

4. Har du et eller flere hjemmeboende børn

Nej 0

Ja, 0-6 år 1

Ja, 7-14 år 2

Ja, > 14 år 3

5. Hvilken uddannelse har du (Sæt kun et kryds)

Under uddannelse 1

Ingen uddannelse (folkeskole) 2

Gymnasial uddannelse 3

Erhvervsuddannelse 4

Kort videregående uddannelse (under 3 år) 5

Mellemlang videregående uddannelse (3-4 år) 6

Langvarig videregående uddannelse (5 år og derover) 7

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6. Hvad er din aktuelle beskæftigelses situation? (Du må gerne sætte mere end et kryds)

Studerende 1

Arbejdsløs 2

Førtidspensionist 3

Efterlønsmodtager 4

Pensioneret 5

I arbejde på deltid 6

I arbejde på fuldtid 7

Sygemeldt 8

7. Hvordan vil du kategorisere dit arbejde mht. fysisk belastning? (Sæt kun et kryds)

Ikke i arbejde 0

Ikke fysisk belastende - overvejende stillesiddende 1

(fx skole, kontor, chauffør, etc.)

Moderat fysisk belastende - involverer nogen fysisk aktivitet 2

(fx går, løfter, bærer let, etc.)

Meget fysisk belastende – overvejende tungt arbejde 3

(fx bærer tungt, gartner, etc.)

BEHANDLINGSFORLØB (Sæt kun et kryds ved hver)

8. I forbindelse med din behandling blev du opereret?

Ingen operation 0 Mastektomi 1 Bryst bevarende 2 Andet 3________________________

9. Fik du fjernet lymfeknuder?

Nej 0 Ja 1, skildvagt lymfeknude biopsi Ja 2 , antal ____________

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10. Hvilket kemoterapi regime modtog du?

3 x epirubicin-cyklofosfamid (CEF)/3 x Taxotere 1 6 x Taxotere 2

Andet 3________________________

11. Har du modtaget/modtager du strålebehandling?

Nej 0 Ja 1

12. Har du modtaget/ modtager du efterbehandling?

Nej 0 Ja, endokrin 1 Ja, herceptin 2 Ja, andet 3 ___________________

13. Er du højre eller venstre håndet? Blev du opereret på den side?

a, (dominant) 1 Nej, (non-dominant) 2

14. Før din udskrivelse fra hospitalet- blev du da introduceret til et øvelsesprogram for brystopereret?

Nej 0 Ja, Kirsten Tørsleffs øvelser 1 Ja 2___________________________________________

15. Udførte du øvelser for bryst opereret (bev. træning, selv massage, etc, Kirsten Tørsleff) indtil din deltagelse i Krop og Kræft?

Nej 0 Ja, 3 x ugentlig 1 Ja, daglig 2

16. I perioden inden du påbegyndte træning i Krop og Kræft, udførte du regelmæssig (1-3x ugtlg) styrketræning af armene?

Nej 0 Ja, i kommunal regi 1__________________ Ja, fysioterapi klinik 2 Ja, på egen hånd 3

SENFØLGER I HÅND OG ARM

17. I løbet af de sidste tre måneder har du observeret en forskel i størrelse mellem højre og venstre side (Sæt kryds hvor relevant)

Ingen forskel 0

Ja, Hånd 1

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Ja, Underarm 2

Ja, Overarm 3

Ja, Bryst 4

18. Hvis der var en forskel, vil du mene at størrelsesforskellen i gennemsnit var (Sæt kun et kryds)

Meget lidt, du var den eneste som kunne se det 1

Synlig for dem som kender dig, men ikke overfor fremmede 2

Meget synlig 3

19. Har armen/ området, på den opereret side, i løbet af de sidste tre måneder: (Sæt kun et kryds)

a. Føltes tung Slet ikke 0 Lidt 1 Meget 2

b. Føltes stiv Slet ikke 0 Lidt 1 Meget 2

c. Føltes hævet Slet ikke 0 Lidt 1 Meget 2

d. Føltes som om den har tabt styrke Slet ikke 0 Lidt 1 Meget 2

e. Føltes snurrende Slet ikke 0 Lidt 1 Meget 2

f. Føltes smertefuld Slet ikke 0 Lidt 1 Meget 2

g. Haft spændt hud Slet ikke 0 Lidt 1 Meget 2

20. Er du blevet diagnosticeret med lymfødem? (Sæt kun et kryds)

Nej 0 Ja 1

HVIS NEJ FORTSAT TIL 25, - HVIS JA FORTSÆT

21. Af hvem blev du diagnosticeret: (Sæt kun et kryds)

Egen læge 1

Behandlende onkolog 2

Lymfødem fysioterapeut 3

Anden (angiv hvem) _______________________ 4

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22. Påbegyndt du efterfølgende lymfødem behandling hos en

Ingen behandling 1

Lymfødem fysioterapeut på sygehus 2

Lymfødem fysioterapeut privat 3

Anden (angiv hvilken)________________________ 4

Er du fortsat i behandling for lymfødem Nej 0 Ja 1

Navn på behandler:_________________________________________________

23. Hvornår blev din lymfødem diagnosticeret (Sæt kun et kryds)

Inden deltagelse i krop og kræft 1

Under deltagelse i krop og kræft 2

Inden for en måned efter deltagelse i krop og kræft 3

1-3 måneder efter deltagelse i krop og kræft 4

4-6 måneder efter deltagelse i krop og kræft 5

7-12 måneder efter deltagelse i krop og kræft 6

>12 måneder efter deltagelse i krop og kræft 7

24. Har du en opfattelse af at en af at en begivenhed udløste din lymfødem (Sæt kun et kryds)

Taget på i kropsvægt 1

Udførte tungt løft 2

Sår/rift/infektion 3

Tilskadekomst 4

Ved ikke 5

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Andet (angiv hvad) 6 ______________________________

FYSISK AKTIVITET (Sæt kun et kryds)

25. Hvordan vurdere du din fysiske styrke indenfor de sidste tre måneder?

Meget dårlig 1 Dårlig 2 Moderat 3 God 4 Meget god 5

26. Hvordan vurdere du din kondition indenfor de sidste tre måneder?

Meget dårlig 1 Dårlig 2 Moderat 3 God 4 Meget god 5

27. Hvordan vurdere du dit energiniveau indenfor de sidste tre måneder?

Meget lavt 1 Lavt 2 Moderat 3 Højt 4 Meget højt 5

28. Hvilket fysisk aktivitetsniveau passer bedst på dig indenfor de sidste 3 måneder?

Stillesiddende 1

(Læser, ser fjernsyn/anden stillesiddende beskæftigelse)

Gå- og/eller cykelture under 3 timer om ugen 2

Regelmæssig fysisk aktiv mindst 3 timer om ugen 3 hvilket_______________________________________

Hård fysisk træning mere end 4 timer om ugen 4 hvilket

29. Har du udført styrketræning for armene, minimum 1-3 gange om ugen siden din afslutning i krop og kræft?

Nej 0

Ja, de første tre måneder 1

Ja, det første halve år 2

Ja, det første år 3

Ja, jeg styrketræner fortsat 4

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30. Hvis Ja, træner du dine arme med belastninger (kilo) svarende til

2-3 sæt af 5-8 gentagelser 1

2-3 sæt af 8-12 gentagelser 2

2-3 sæt af 12-15 gentagelser 3

Andet, (angiv hvad)_______________________ 4

31. Tak for din deltagelse. Er der noget du evt. vil tilføje?

Må jeg kontakte dig igen?

Nej 0 Ja 1

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Appendix D: Study 3

BCRL information to participants

EORTC QLQ- BR23 questionnaire

Subjective BCRL outcomes structured interview

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Informationomlymfødemtildeltagerei

”Etrandomiseretkontrolleretforsøgmedopsporende

interventionogfysiskaktivitetforikke‐træningsvante

patientermedbrystkræftiadjuverendekemoterapi”

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Efterenoperationmedfjernelseaflymfekirtleribrystetogarmhulenerdetalmindeligt,atoverkroppen,brystet,armenog/ellerhåndenpådenopereredesidekanhavetendenstilathævedeførstemåneder,hvorefterhævelsenaftageriløbetafenugestid.Hosenmindreprocentdel(20‐30%)opstårlymfødem.Lymfødemerenkronisktilstandogkarakteriseressomenvedvarendehævelseafoverkroppen,brystet,armenog/ellerhåndenpådenopereredeside.Tilstandenkanopståiforlængelseafoperationenellerførstflereårsenere,menoftestiløbetafdeførstetoårefteroperationen.

Idagvedviikke,hvorfornogleudviklerlymfødemogandreikkegør.Selvomårsagernebagerukendte,erenrækkerisikofaktorerblevetidentificeret.Dinrisikoforatudviklelymfødemersåledesøget,hvisdu: harfåetfjernetyderligerelymfekirtlerend

skildvagt‐lymfekirtlerneiarmhulen harfåetfjernetbrystet erovervægtig

Endvidereserdetudtilat stråleterapi kemoterapi fysiskinaktivitet

ogsåøgerrisikoenforatudviklelymfødem.

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Studiervedrørendefysisktræningogudviklingaflymfødemindikerer,atmotionikkeøgerrisikoenforatudviklelymfødem.Detteerogsåvoreserfaring,ogetnyligtpublicerettværsnits‐studiefinder,at6ugersdeltagelseiKropogKræftikkeerassocieretmedenøgetrisikoforatudviklelymfødem.Mendermanglerstadigvidenomspecifikketræningsformer,ogderforvilderløbendeblivespurgtindtilvelkendtesymptomerpåbegyndendelymfødemunderdindeltagelseiprojektet.Ydermere,hvisduopleversymptomersomstårpåioverénuge,ellerhvisdueritvivl,børduhenvendedigtilKiraiprojektteamet(35457362),damankanhindrelymfødemetiatudviklesigyderligerevedatmodtagerelevantbehandlingtidligtiforløbet.

Desymptomer,somduskalværeopmærksompåioverkroppen,brystet,armenog/ellerhånden,er: hævelseiløbetafdagenudennogen

nævneværdiggrund,mærkerihudenefterf.eks.ur,ring,BH‐stopperosv.

tyngde‐ogtræthedsfornemmelse urooginogletilfældesmerter spændingsfornemmelse

Viserfremtilogglæderostilatstøttedigiatblivemerefysiskaktividekommendemåneder.

MangevenligehilsnerTom,Christina,Christian,BirgitogKira

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DANISH

EORTC QLQ - BR23

Patienter fortæller undertiden, at de har følgende symptomer eller problemer. Anfør venligst, i hvilket omfang De har haft disse symptomer eller problemer inden for den forløbne uge. Besvar spørgsmålene ved at sætte en ring omkring det tal, som passer bedst til Dem.

I den forløbne uge: Slet ikke Lidt En del Meget 31. Var De tør i munden? 1 2 3 4

32. Smagte mad og drikke anderledes end normalt? 1 2 3 4

33. Havde De ondt i øjnene, var øjnene irriterede eller løb de i vand? 1 2 3 4

34. Har De haft hårtab? 1 2 3 4

35. Skal kun udfyldes, hvis De har haft hårtab: Var De ked af hårtabet? 1 2 3 4

36. Følte De Dem syg eller utilpas? 1 2 3 4

37. Havde De hedeture? 1 2 3 4

38. Havde De hovedpine? 1 2 3 4

39. Har De følt Dem mindre fysisk tiltrækkende på grund af Deres sygdom eller behandling? 1 2 3 4

40. Har De følt Dem mindre kvindelig på grund af Deres sygdom eller behandling? 1 2 3 4

41. Havde De svært ved at se på Dem selv nøgen? 1 2 3 4

42. Har De været utilfreds med Deres krop? 1 2 3 4

43. Var De bekymret for, hvordan dit helbred bliver i fremtiden? 1 2 3 4

I de sidste fire uger: Slet ikke Lidt En del Meget 44. I hvilket omfang var De interesseret i sex? 1 2 3 4

45. I hvilket omfang var De seksuelt aktiv? (med eller uden samleje) 1 2 3 4

46. Besvar kun dette spørgsmål, hvis De har været seksuelt aktiv: I hvilket omfang nød De sex? 1 2 3 4 Vær venlig at fortsætte på næste side

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DANISH

I den forløbne uge: Slet ikke Lidt En del Meget 47. Havde De smerter i armen eller skulderen? 1 2 3 4 48. Var armen eller hånden hævet? 1 2 3 4 49. Var det svært at løfte armen eller bevæge den til siden? 1 2 3 4 Med "brystområdet" forstås enten det operede bryst eller det område, hvorfra brystet er fjernet: I den forløbne uge: Slet ikke Lidt En del Meget 50. Har De haft smerter i "brystområdet"? 1 2 3 4 51. Var "brystområdet" hævet? 1 2 3 4 52. Var "brystområdet" ømfindtligt? 1 2 3 4 53. Har De haft hudproblemer i "brystområdet" (fx. kløe, tørhed, afskalning)? 1 2 3 4 © Copyright 1994, 1995 EORTC Study Group on Quality of Life. All rights reserved. Version 1.0

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CIRE lymfødem screening      Pt. ID__________________ 

          Dato __________________ 

Spørges v baseline, uge 6, 12 og 39 uger.  Sæt en ring omkring de svar der passer bedst. 

1. Kirurgi  

Højre/venstre 

Lumpektomi                                                                                                                                                      Mastektomi                                                                                                                                                             Expander     

2. Lymfekirtler fjernet  

Skildvagt lymfekirtel                                                                                                                                                                       

Aksil dissektion                                                                                                                                                        Evt. antal fjernet____________ 

3. BMI_______________ 

4. Notere om deltager er i forløb (forebyggende el behandlende) for lymfødem og i så fald hvornår.  

Baseline Nej/Ja_______________ 

6 uger Nej/Ja_________________ 

12 uger Nej/Ja________________ 

39 uger Nej/Ja________________ 

5. Har du observeret en forskel i størrelse mellem den opereret og ikke opereret side i løbet af den sidste uge?  

 

 

 

 

 

 

 

 

 

Baseline  Uge 6  Uge 12  Uge 39 

Nej   Nej    

Nej     

Nej     

Ja (hvor)  Ja (hvor)  Ja (hvor)  Ja (hvor) Fingre Hånd 

Fingre Hånd 

Fingre Hånd 

Fingre Hånd 

Underarm  Underarm  Underarm  Underarm 

Overarm  Overarm  Overarm  Overarm Bryst Torso  

Bryst Torso  

Bryst Torso  

Bryst Torso  

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.  

 

           Pt. ID__________________       

 

6. Har du bemærket en eller flere tilstande på den opereret side i løbet af den sidste uge (0=ingen, 10=værst tænkelig)  

Tilstand  Baseline  Uge 6  Uge 12  Uge 39 

Føltes tung  0 1 2 3 4 5 6 7 8 9 10  0 1 2 3 4 5 6 7 8 9 10 0 1 2 3 4 5 6 7 8 9 10 0 1 2 3 4 5 6 7 8 9 10 

Føltes hævet  0 1 2 3 4 5 6 7 8 9 10  0 1 2 3 4 5 6 7 8 9 10 0 1 2 3 4 5 6 7 8 9 10 0 1 2 3 4 5 6 7 8 9 10 

Smerter  0 1 2 3 4 5 6 7 8 9 10  0 1 2 3 4 5 6 7 8 9 10 0 1 2 3 4 5 6 7 8 9 10 0 1 2 3 4 5 6 7 8 9 10 

Spændt hud  0 1 2 3 4 5 6 7 8 9 10  0 1 2 3 4 5 6 7 8 9 10 0 1 2 3 4 5 6 7 8 9 10 0 1 2 3 4 5 6 7 8 9 10 

 

 

 

Evt. Bemærkninger: (F.eks bevæge indskrænkning, serom tømning, føleforstyrrelser etc.)