use of imaging in surveillance of women with early stage breast cancer

Use of imaging in surveillance of women with early stage

breast cancer

Robin J. Bell,* Max Schwarz,†‡ Pamela Fradkin* and Susan R. Davis**Women’s Health Program, School of Public Health and Preventive Medicine, Faculty of Medicine, Nursing and Health Sciences, Monash University,Melbourne, Victoria, Australia†Department of Medicine, Central Clinical School, Monash University, Melbourne, Victoria, Australia and‡Bayside Health, Alfred Hospital, Melbourne, Victoria, Australia

Key words

breast cancer, imaging, surveillance, mammography.

Correspondence

Professor Robin Bell, Women’s Health Program, Schoolof Public Health and Preventive Medicine, Faculty ofMedicine, Nursing and Health Sciences, MonashUniversity, Level 6, The Alfred Centre, 99 CommercialRoad, Melbourne, Vic. 3004, Australia.Email: [email protected]

R. J. Bell MBBS, PhD, MPH, FAFPHM; M. Schwarz

MBBS, FRACP, FACP, FAChPM; P. Fradkin MBBS;S. R. Davis MBBS, PhD, FRACP.

Accepted for publication 31 May 2012.

doi: 10.1111/j.1445-2197.2012.06229.x

Abstract

Background: There is no evidence of benefit in terms of survival or quality of life forintensive surveillance of women with early breast cancer (BC) and current guidelinesreflect this. We have examined whether Victorian women, nearly 4 years from adiagnosis of localized BC, were being managed according to these guidelines.Methods: Participants are women in the BUPA Health Foundation Health and Well-being after Breast Cancer prospective cohort study. All participants completed anenrolment questionnaire within 12 months of diagnosis and then completed follow-upquestionnaires every 12 months thereafter. In the third follow-up questionnaire, com-pleted nearly 4 years from the time of diagnosis, women were asked about imagingtests they had in the previous 12 months.Results: The analysis was completed on 673 women who were stage 1 at the time ofdiagnosis and had not reported evidence of recurrence or a new BC since diagnosis. Ofthe 673, 603 (89.5%) reported having had a mammogram in the previous 12 monthsand 319 (52.9% of those having a mammogram) reported a breast ultrasound. Seventy-one per cent of women reported no other imaging investigations in theprevious 12 months.Conclusions: Our study shows that, nearly 4 years from diagnosis, Australian prac-titioners are generally adhering to guidelines about imaging surveillance of BC sur-vivors. Practitioners could use the guidelines for the education of BC survivors aboutappropriate health surveillance.

Introduction

For women who have been treated for sporadic early stage breastcancer (BC), basic surveillance consisting of history, physical exami-nation and mammography is supported by the American Society forClinical Oncology.1 In Australia, similar guidelines have been pro-duced by the National Health and Medical Research Council,2 eventhough there is no evidence from randomized trials that routinemammography in women with a personal history of BC improvessurvival from either new ipsilateral or contralateral disease.3

Most BC recurrences are detected because they become sympto-matic, and evidence of benefit in terms of survival or quality of lifefor intensive surveillance (including a range of imaging modalities)compared with surveillance where investigations are promptedby clinical indications is lacking.4 Chest X-rays (CXRs) are not

recommended for detecting asymptomatic recurrence because oflow sensitivity.5 Both chest and abdomino-pelvic computerized axialtomography (CAT) examinations are associated with false positiveresults in women with BC.6,7 Bone metastases are usually diagnosedbecause they present symptomatically, even among women havingregular bone scans.8 Although both magnetic resonance imaging(MRI) and positron emission tomography (PET) are sensitive for thedetection of BC, neither is recommended in the routine care ofwomen with a personal history of BC.9,10

Given the current recommendations, our aim was to examinewhether women with localized BC at diagnosis and currently nearly4 years from diagnosis, and free of recurrence or new BC, were beingmanaged according to these guidelines or whether there was evidenceof the use of imaging modalities for ‘surveillance’ of women with ahistory of early BC outside of management guidelines.

BREASTANZJSurg.com

© 2012 The AuthorsANZ Journal of Surgery © 2012 Royal Australasian College of Surgeons ANZ J Surg 83 (2013) 129–134

Methods

This study was carried out within the BUPA Health FoundationHealth and Wellbeing after Breast Cancer Study which is a largeprospective cohort study in Australia of women diagnosed betweenJune 2004 and December 2006 with their first episode of invasiveBC. The participants were recruited by invitation through the state-based Victorian Cancer Registry.11 As it is a statutory requirementfor organizations involved in the diagnosis of cancer to notify allnew cancer diagnoses to the Registry and as there was a low rate ofrefusal of the invitation to participate in the study, women in thestudy are representative of all women diagnosed with invasive BC inthe state in terms of age, tumour size and location of residence. Thedetails of the individual patient pathology were provided to ourstudy by the Victorian Cancer Registry. Approval for our study hasbeen given by both the Human Research Ethics Committee of theCancer Council of Victoria as well as the Standing Committee onEthics in Research Involving Humans of Monash University, andwritten consent was provided by all participants.

We aimed for all participants to complete the enrolment question-naire (EQ) within 1 year of diagnosis and the average time betweendiagnosis, and completion of the EQ was 41 weeks (with 90% ofEQs completed between 8 and 58 weeks from diagnosis).12 The EQincluded questions about demographic details, past medical history,details of surgery and other treatments, and questions about thewoman’s understanding of her cancer. Participants completedfollow-up questionnaires (FQs) every year following completion ofthe EQ (FQ1, FQ2, FQ3). FQs included questions about recurrentdisease or the development of a new primary BC, about furthertreatments, other chronic diseases, as well as validated question-naires to assess menopausal symptoms and well-being.

The data analysed in this manuscript are from the third follow-upquestionnaire (FQ3), which was completed on average 3.8 yearsfrom diagnosis (95% were completed between 3.0 and 4.3 yearsfrom diagnosis). The data relate to questions about specificfollow-up investigations within the previous 12 months includingmammography, breast ultrasound (US), CXR, whole body nuclearbone scan (NBS) (as distinct from a dual energy X-ray absorptiom-etry scan for bone density), CAT scan, MRI scan and PET scan.

For the purposes of this analysis, any participant who reported thepresence of active BC (either recurrence or a new primary BC) inany of the FQs up to and including FQ3 was excluded from thisanalysis as the investigation of that active disease may have involveda range of imaging modalities.

As the guidelines about surveillance relate to women with ‘local-ised BC’, this analysis is also limited to women with stage 1 disease(tumour diameter of �20 mm) with no evidence of tumour cells inthe lymph nodes or other parts of the body).13 Disease which isclassified as beyond stage 1 can be so classified because the tumouris >20 mm in diameter or because BC cells have been found in thelymph nodes or in other parts of the body. As there is no question thatstage 1 tumours are small and localized to the breast, this analysiswas limited to women with stage 1 disease at diagnosis so there wasno question that the current guidelines would apply to these women.

The tests the women reported were classified as being ordered inrelation to their BC, to another condition or there was no obvious

indication for the test or tests. In FQ3, the women were askedwhether they had been investigated for a possible recurrence or newBC since completion of the previous questionnaire (and if so,whether on the basis of the test results there was any evidence ofrecurrence or a new BC). They were asked if they had surgery relatedto their BC since their previous questionnaire (as the need forsurgery such as a reconstruction could be the basis for imaging).They were also asked whether they had been hospitalized since theprevious questionnaire (and if so was it due to their BC or anothercondition; if due to another condition, what was that condition) andwhether they had experienced a list of specific conditions includinga venous thrombosis or pulmonary embolus, fracture, another canceror other serious medical conditions. We also asked them if they wereparticipating in a trial as this may have prompted the use of imagingmodalities, in which case we classified any tests they had as relatedto their BC.

As the use of aromatase inhibitors (AIs) is associated with mus-culoskeletal pain and could prompt the use of NBS, we have indi-cated numbers of women who reported using an AI among thosewomen who reported having tests other than mammography orbreast US.

The results are reported as frequencies and percentages. Therewas no formal statistical testing performed in relation to the distri-bution of women on AIs and use of NBS in the groups reporting testsother than mammography and breast US.

Results

Of the 1683 women with a first diagnosis of invasive BC whocompleted the EQ, 1444 remained in the study by FQ3 (see Fig. 1).Two hundred and thirty-nine women had been lost to the study bythis stage because: they had died while remaining a part of the study(64); they had actively withdrawn from the study (contacted ourgroup to tell us they no longer wanted to remain in the studyafter which they may also have subsequently died) (54); they hadpassively withdrawn from the study (did not return the next

Fig. 1. Numbers of women completing the enrolment questionnaire andeach of the first three follow-up questionnaires in the BUPA Health Foun-dation Health and Wellbeing after Breast Cancer Study. %s are of the1683 women who completed the EQ. EQ, enrolment questionnaire; FQ,follow-up questionnaire.

130 Bell et al.

© 2012 The AuthorsANZ Journal of Surgery © 2012 Royal Australasian College of Surgeons

questionnaire despite being reminded to do so by both mail andtelephone and then may also have subsequently died) (115); or theywere lost to follow-up (6).

Of the 1444 women who completed FQ3, 1358 had not reportedany active disease (either recurrence or new BC) in any FQ up to andincluding FQ3 (86 women who remained in the study at FQ3 hadreported and been treated for active disease by this time). Of the1358 women free of active disease by FQ3, 673 were stage 1 at thetime of diagnosis and so are included in this analysis.

The characteristics of the complete sample of women recruited tothis study have been published elsewhere,11 however the sample ofwomen in this analysis represent women alive and free of evidenceof active disease nearly four years from the time of diagnosis. The

mean age of this sample at diagnosis was 58.0 (95% CI 40.0 to 75.2)years and 87% were either oestrogen or progesterone receptor posi-tive, or both.

Mammography and breast US as reported in FQ3

Of the 673 women, 603 (89.5%) reported having had a mammogramin the previous 12 months, 325 reported a breast US in the previous12 months (48.3%) and 319 (47.4% of the total and 52.9% of thosehaving a mammogram) reported both examinations (Fig. 2). Themean age of the women who had a breast US was 55.8 (SD 10.4)years was significantly lower than the mean age of women who didnot have a breast US 60.1 (SD 10.6) years (mean difference 4.3 (95%CI 2.7 to 5.9 years)). Only 64 (9.5%) women had not had either oneor other of these examinations in the previous 12 months. Of these64, 18 had a history of bilateral mastectomy.

Other imaging modalities (CXR, NBS, CAT, MRI,PET) as reported in FQ3

Of the 673 women, 480 (71%) reported none of these investigationsin the previous 12 months. Of the remaining 193 women, 129(19.2% of the 673) had only one of the investigations (Table 1). Themost commonly reported single investigation was a CXR, followedby NBS, CAT scan, MRI and then PET scan. Overall, two thirds ofwomen having a single investigation did not report an indication forthe test and this was true for each individual test except for a PETscan (where only five were performed). There was not an over-representation of women on an AI in the group reporting an NBScompared with women reporting one of the other investigations.

Forty-six women reported having two of the investigations(Table 2). The most commonly performed combination of tests wasa CXR/NBS followed by a combination of CAT/MRI and CXR/CAT. Overall, just over half of the women having two tests had anobvious indication for the tests, although this proportion variedwidely depending on the combination of the tests performed.

Sixteen women reported having three of the investigations(Table 3). The most common combination was CXR/CAT/MRI.Two thirds of the women having three tests had an obvious indica-tion for having the tests.

Two women reported having four of the investigations (one hadCXR, NBS, CAT and MRI, and the other had NBS, CAT, MRI andPET) and both of them had been investigated for other serious healthconditions.

Fig. 2. Numbers and proportions of women reporting in the thirdfollow-up questionnaire that they had a mammogram (M), breast ultra-sound (US), both or neither in the previous 12 months.

Table 1 Numbers of women reporting having only one of CXR, NBS, CAT, MRI or PET in the previous 12 months showing whether the test was performedfor their BC, other morbidity or there was no apparent indication for the test

CXR NBS CAT MRI PET Total (%)

BC related 2 0 2(AI, n = 1)

4(AI, n = 3)

0 8(6.2)

Other morbidity 19(AI, n = 2)

7(AI, n = 3)

6 1 3(AI, n = 1)

36(27.9)

No apparent indication (%) 37(AI, n = 15)

(63.8)

22(AI, n = 7)

(75.9)

13(AI, n = 2)

(61.9)

11(AI, n = 5)

(68.8)

2(40.0)

85(65.9)

Total (%) 58(44.9)

29(22.5)

21(16.3)

16(12.4)

5(3.9)

129

BC, breast cancer; CAT, computerized axial tomography; CXR, chest X-ray; MRI, magnetic resonance imaging; NBS, nuclear bone scan; PET, positron emissiontomography. (AI) 39 women taking an aromatase inhibitor as reported in the third follow-up questionnaire.

Imaging in breast cancer surveillance 131


There was no obvious association between the use of an AI atFQ3 and the reporting of an NBS in women having more than oneinvestigation.

Discussion

Our study shows that in relation to mammography, nearly 4 yearsfrom diagnosis, Australian practitioners are adhering to guidelinesabout imaging surveillance of BC survivors. Most women are havingannual mammograms; however, more than half of women who hada mammogram also reported having a breast US. The majority ofwomen (71%) did not have any other imaging tests apart from these.

Breast US is not listed in either the ‘recommended’ or the ‘notrecommended’ list of investigations for routine surveillance for BC.1

In our sample, very few women had a breast US without a mammo-gram and so breast US is essentially being used as supplemental tomammography where clinically indicated. The lower mean age ofwomen reporting breast US is consistent with the use of mammog-raphy in younger women who are more likely to have denser breasttissue. Although breast US is generally considered a safe procedureand has been shown to increase the diagnostic yield in a high-riskpopulation, it will also increase substantially the number of womenhaving a biopsy.14 Even though the sensitivity is improved by theaddition of US, despite the extra cancers diagnosed, the extra falsepositive results result in a reduced positive predictive value of thecombination of tests.

Where women did have one or more of tests other than mammo-graphy or breast US, the more tests a woman had, the more likely it

was that there was a specific reason identified for the tests beingordered, either in relation to her BC or to another medical condition.The use of AIs is associated with musculoskeletal pain in up to 40%of users15 and could prompt the use of an NBS to exclude bonymetastases; however, we found no association between the use of anAI and the use of a NBS either alone or in combination with othertests. The frequency of use of isolated CXRs and NBS suggests thatthese tests may be being used for some informal ‘surveillance’ bysome practitioners, although it is also possible that some womenfailed to recall indications for a CXR such as a chest infection.

The strengths of our study include that our cohort of women withBC was recruited through the state cancer registry and we have ahigh rate of retention in our study. This means that our findings canbe generalised to all Victorian women with their first episode ofinvasive BC who remain free of active disease. An additionalstrength of our study is that the data were collected on average nearly4 years from diagnosis and so provide an indication of adherence toguidelines well beyond the initial period of acute BC treatment. ‘Arecent survey of surgeons and radiologists in the UK found thatthe most frequently reported time at which women were dischargedfrom surveillance mammography was 10 years, however wheninitiation, frequency and cessation of mammography were all con-sidered there were over 50 different regimens of surveillance mam-mography followed’.16

A potential weakness of our study is that there may have beenindications for the use of the imaging modalities which were notreported by women in FQ3. We tried to minimize this issue by givingthe women multiple opportunities within FQ3 to record if the inves-

Table 2 Numbers of women having a combination of two of the following tests: CXR, NBS, CAT, MRI or PET, in the previous 12 months including whetherthe tests were performed for their BC, other morbidity or there was no apparent indication for the tests

CXR and NBS CAT and MRI CXR and MRI MRI and PET CXR and CAT NBS and CAT CAT and PET NBS and MRI Total (%)

BC related 1 1(AI, n = 1)

1 1 0 0 0 1 5(10.9)

Othermorbidity

3(AI, n = 1)

5(AI, n = 1)

2 0 7(AI, n = 2)

1 1 0 19(41.3)

No apparentindication

11(AI, n = 2)(73.3%)

3(AI, n = 1)(33.3%)

00%

00%

2(AI, n = 2)(22.2%)

5(AI, n = 1)(83.3%)

1(50%)

00%

22(47.8)

Total (%) 15(32.6)

9(19.6)

3(6.5)

1(2.2)

9(19.6)

6(13.0)

2(4.3)

1(2.2)

46

BC, breast cancer; CAT, computerized axial tomography; CXR, chest X-ray; MRI, magnetic resonance imaging; NBS, nuclear bone scan; PET, positron emissiontomography. (AI) 11 women taking an aromatase inhibitor as reported in the third follow-up questionnaire.

Table 3 Numbers of women reporting having a combination of three of the following tests: CXR, NBS, CAT, MRI or PET, in the previous 12 months,including whether the tests were performed for their BC, other morbidity or there was no apparent indication for the tests

CXR, NBS, CAT CXR, CAT, MRI CXR, NBS, MRI NBS, CAT, MRI Total (%)

BC related 1 2(AI, n = 1)

3(18.8)

Other morbidity 2 5(AI, n = 3)

1† 8(50.0)

No apparent indication 3†(AI, n = 1)(60.0%)

1†(14.3%)

00%

1(AI, n = 1)(100%)

5(31.2)

Total (%) 5(31.3)

7(43.7)

3(18.7)

1(6.3)

16

†Women under 50 years of age at diagnosis. BC, breast cancer; CAT, computerized axial tomography; CXR, chest X-ray; MRI magnetic resonance imaging; NBS,nuclear bone scan. (AI) 6 women taking an aromatase inhibitor as reported in the third follow-up questionnaire.

132 Bell et al.


tigation was for reasons related to their BC, investigation of a rangeof other specified medical conditions as well as conditions not spe-cifically listed. Ideally, one would review medical records to estab-lish the indications for the tests performed; however, as this is acommunity-based study with participants living throughout the stateof Victoria, reviewing all the medical records was not feasible.

The national expenditure on cancer care in the United States in2006 was $104 billion, with the largest single expenditure being onBC.17 Costs are increasing because the costs of new treatments areincreasing and the proportion of people receiving treatment is alsoincreasing.18 Another contributor to cost is the surveillance of thehealth of people living with a cancer diagnosis. The marginal cost ofchoosing an intensive rather than a minimal surveillance regimen forwomen with stage I or II BC in the United States was estimated to be$1 billion in the year 2000.19 Publication of formal guidelines hasbeen shown to be followed by reduced costs of surveillance.20

Moving away from scheduled to targeted investigation may not onlyreduce costs but also reduce patient anxiety.21

Our data would suggest that in general, Australian health-careproviders are practising in line with guidelines. The use of breast USas an ancillary investigation to mammography in this setting isunderstandable; however, given the observed prevalence of the com-bined use of mammography and breast US in this group, practition-ers need to be aware of the impact of introducing breast US tostandard mammography on the false positive rate. Practitionerscould use the guidelines for the individual education of BC survivorsabout the use of imaging in their health surveillance. BC advocacygroups could also play a role in this educative process.

Acknowledgements

The authors wish to thank the study participants and the members ofour Study Advisory Group: Dr Jacquie Chirgwin, A/Professor JohnCollins, Professor Graham Giles, Mr Peter Gregory, Mr StewartHart, Miss Suzanne Neil and Mrs Avis McPhee. The authors alsowish to thank members of the research team of the Health andWellbeing after Breast Cancer study, without whose hard work thislarge cohort study would not be possible (Penny Robinson, Maria LaChina, Dr Mary Panjari and Jo Bradbury). Finally, we thank MsHelen Farrugia, Director of Information Systems, and ProfessorGraham Giles, Director, of the Victorian Cancer Registry, for theirongoing support of this study.

Funding sources

This work was supported by the BUPA Health Foundation (previ-ously the Medical Benefits Fund of Australia Limited Foundation)(to SRD and RJB), the National Health and Medical ResearchCouncil of Australia (Grants no. 219279 to SRD and RJB, 490938 toSRD), Novartis Oncology Australia (SRD), the L.E.W. Carty Trust,the Jack and Robert Smorgon Families Foundation, Connie andCraig Kimberley and Roy Morgan Research (all to SRD and RJB).This Research Project was also supported by the Victorian Govern-ment through a Victorian Cancer Agency Public Health ResearchFellowship (to RJB).

References1. Khatcheressian JL, Wolff AC, Smith TJ et al. American Society of

Clinical Oncology 2006 update of the breast cancer follow-up and man-agement guidelines in the adjuvant setting. J. Clin. Oncol. 2006; 24:5091–7.

2. National Health and Medical Research Council. Clinical PracticeGuidelines for the Management of Early Breast Cancer – SecondEdition. 2001. [Cited 27 Aug 2012.] Available from URL: http://www.nhmrc.gov.au/guidelines/publications/cp74

3. Grunfeld E, Noorani H, McGahan L et al. Surveillance mammographyafter treatment of primary breast cancer: a systematic review. Breast2002; 11: 228–35.

4. The GIVIO Investigators. Impact of follow-up testing on survival andhealth-related quality of life in breast cancer patients. A multicenterrandomized controlled trial. The GIVIO Investigators. JAMA 1994; 271:1587–92.

5. Kokko R, Hakama M, Holli K. Role of chest X-ray in diagnosis of thefirst breast cancer relapse: a randomized trial. Breast Cancer Res. Treat.2003; 81: 33–9.

6. Mehta VK, Goffinet DR. Unsuspected abnormalities noted on CTtreatment-planning scans obtained for breast and chest wall irradiation.Int. J. Radiat. Oncol. Biol. Phys. 2001; 49: 723–5.

7. Drotman MB, Machnicki SC, Schwartz LH, Winston CB, Yoo HH,Panicek DM. Breast cancer: assessing the use of routine pelvicCT in patient evaluation. AJR Am. J. Roentgenol. 2001; 176: 1433–6.

8. Tomin R, Donegan WL. Screening for recurrent breast cancer – itseffectiveness and prognostic value. J. Clin. Oncol. 1987; 5: 62–7.

9. Gorechlad JW, McCabe EB, Higgins JH et al. Screening for recurrencesin patients treated with breast-conserving surgery: is there a role forMRI? Ann. Surg. Oncol. 2008; 15: 1703–9.

10. Isasi CR, Moadel RM, Blaufox MD. A meta-analysis of FDG-PET forthe evaluation of breast cancer recurrence and metastases. Breast CancerRes. Treat. 2005; 90: 105–12.

11. Lijovic M, Davis SR, Fradkin P et al. Use of a cancer registry is pref-erable to a direct-to-community approach for recruitment to a cohortstudy of wellbeing in women newly diagnosed with invasive breastcancer. BMC Cancer 2008; 8: 126.

12. Lijovic M, Davis SR, Fradkin P et al. The relationship between knowl-edge of family history and cancer characteristics at diagnosis in womennewly-diagnosed with invasive breast cancer. Fam. Cancer 2009; 8:299–305.

13. Sobin LH, Wittekind C (eds). Classification of Malignant Tumours, 6thedn. New York: Wiley-Liss, 2002.

14. Berg WA, Blume JD, Cormack JB et al. Combined screening with ultra-sound and mammography vs mammography alone in women at elevatedrisk of breast cancer. JAMA 2008; 299: 2151–63.

15. Dent SF, Gaspo R, Kissner M, Pritchard KI. Aromatase inhibitortherapy: toxicities and management strategies in the treatment of post-menopausal women with hormone-sensitive early breast cancer. BreastCancer Res. Treat. 2011; 126: 295–310.

16. Robertson C, Arcot Ragupathy SK, Boachie C et al. The clinical effec-tiveness and cost-effectiveness of different surveillance mammographyregimens after the treatment for primary breast cancer: systematicreviews registry database analyses and economic evaluation. HealthTechnol. Assess. 2011; 15: v–vi, 1–322.

17. National Cancer Institute, US National Institutes of Health. CancerTrends Progress Report – 2009/2010 update. 2010. [Cited 27 Aug 2012.]Available from URL: http://progressreport.cancer.gov/doc_detail.asp?pid=1&did=2009&chid=95&coid=926&mid=

Imaging in breast cancer surveillance 133


18. Warren JL, Yabroff KR, Meekins A, Topor M, Lamont EB, Brown ML.Evaluation of trends in the cost of initial cancer treatment. J. Natl.Cancer Inst. 2008; 100: 888–97.

19. Schapira DV, Urban N. A minimalist policy for breast cancer surveil-lance. JAMA 1991; 265: 380–2.

20. Mille D, Roy T, Carrere MO et al. Economic impact of harmonizingmedical practices: compliance with clinical practice guidelines in thefollow-up of breast cancer in a French Comprehensive Cancer Center. J.Clin. Oncol. 2000; 18: 1718–24.

21. Smith TJ, Hillner BE. Bending the cost curve in cancer care. N. Engl. J.Med. 2011; 364: 2060–5.

Supporting Information

Additional Supporting Information may be found in the onlineversion of this article:

Appendix SI. Health and Wellbeing after Breast Cancer Study:third follow-up questionnaire.

134 Bell et al.


use of imaging in surveillance of women with early stage breast cancer

Documents