mri to enable local excision

gina.brown@rmh.nhs.uk

Significant Polyp and Early Colorectal Cancer

Imaging for Local Excision

www.slideshare.net/Gina.Brown3

gina.brown@rmh.nhs.uk

Early Rectal CancerGina Brown

Royal Marsden Hospital and Imperial College, London

The Royal Marsden

ERC staging is a problem Data published by the NBOCAP shows 45% of the 9,433 rectal cancers treated by radical resection in the UK annually were either T1 or T2 and 66% were node negative. Despite this 77% those operated on underwent major resection whilst only 11% were locally excised

The Royal Marsden

Assessment of significant polyps

• Tumour boards do not always review significant polyps before definitive treatment is undertaken

• Many eligible patients are not referred/considered for TEM/Local excision procedure

• UK TEM database, 44% of pT1 and 31% of pT2 cancers were incorrectly presumed to be benign preoperatively

• Less than full thickness excision by flexible endoscopic excision or transanal endoscopic surgery – understaging by initial endoscopic assessment

The Royal Marsden

Assessment of ERC• Is it malignant or not?• What is the depth of invasion?• Is there extramural disease?• How should lesion be removed:

EMR/ESD TEM/TAMIS TME APE

The Royal Marsden

Depth of invasion is relevant

Kikuchi R, Dis Colon Rectum. 1995 (12):1286-95

Kikuchi levels classification: distance of SM invasion

nodal metsSM1 superficial 1/3 2%SM2 superficial 2/3 8%SM3 deep 1/3 23%

The Royal Marsden

Konishi, K., Y. Akita, et al. (2003). "Evaluation of endoscopic ultrasonography in colorectal villous lesions." Int J Colorectal Dis

• Large (>/=20 mm wide, >/=5 mm high) or rectal villous lesions were more likely than nonvillous lesions to be misjudged with regard to the differentiation between M/SM-s and non-M/SM-s.

• It is difficult to determine the depth of invasion in villous lesions, especially large or rectal lesions, using only EUS.

• EUS-based evaluation alone cannot determine the appropriate treatment for colorectal villous lesions.

The Royal Marsden

• ERUS in 165 of 494 patients who underwent TEM for rectal cancer.

• It inaccurately staged rectal cancer in 44.8%• No significant difference in the depth of TEM excision

or R1 rate between the patients who underwent ERUS before TEM and those who did not (P= 0.73).

• Colorectal disease 2011, TEMS database

The Royal Marsden

High resolution MRIWithout endorectal coilPixel size 0.6 x 0.6mm

The Royal Marsden

The Royal Marsden

www.slideshare.net/ginabrown_3

• Scan duration = quality• 4-6 NSA/NEX and T2- FSE / TSE• 0.6mm x 0.6mm x 3mm = 1.1mm3 voxel• Adequate coverage – 5cm above top of tumour• Perpendicular to the rectal wall• Low rectal cancer – parallel to anal canal• Ensure discontinuous deposits are covered on high res• Buscopan• Saturation Bands• firm coil placement with secure strapping

The Royal Marsden

The submucosal fold pattern

The Royal Marsden

T staging• Location of tumour – anterior, posterior, r or l lateral• Morphology: annular, semi annular, polypoidal,

ulcerating, mucinous, villous• For annular/ulcerating – location of central invasive

portion vs raised edges• For polypoidal/villous lesions – site of stalk • Invasive margin: nodular infiltrating, broad based

pushing margin

The Royal Marsden

ERC subclassification• T0/early T1sm1 – no evident disruption of the submucosa – entire thickness

of SM appears preserved• T1sm2 – at least 1mm of submucosa is preserved• T1sm3/early T2: full thickness of muscularis propria is preserved but <1mm

submucosa is visible• T2 early >1mm muscularis is preserved• T2/T3a – 0mm of muscularis preserved microscopic invasion beyond

muscularis <1mm – prognosis identical for this subgroup• T3b 1-5mm – good prognosis

The Royal Marsden

Recommended reporting structure for staging early rectal cancer using MRI

• State morphology – flat, polypoidal, mucin containing• Measure diameter and thickness of lesion• If polypoidal –state site and diameter of fibromuscular stalk• If flat – quadrant or clockface location of central depression versus raised rolled edges• Measure extent/diameter of invasive border• Assess degree of preservation of the mucosa, submucosa, muscularis propria layers at

the stalk• Assess lymph nodes for malignant characteristics based on nodal capsule breach or

heterogeneity of signal• Assess height of lesion in relation to anal verge and puborectalis sling• Evaluate extramural veins for discontinuous spread

The Royal Marsden Early stage disease

The Royal Marsden

What is the T stage of this tumour

1. T1 : preservation of >3mm of muscularis and visible submucosal layer

The Royal Marsden

The Royal Marsden

Nodal staging – high resolution MRI must be used

• Criteria for predicting malignancy = mixed signal intensity and/or irregular border (Radiology 2003)

• Size of nodes not a useful predictor (Radiology 2003)

• Accuracy = 85%, sensitivity 83%, specificity 86% (BJS 2003)

The Royal Marsden

Discontinuous vascular invasion

The Royal Marsden

Where are the nodes?

EUS coverage MRI coverage

MRI coverage

EUS

The Royal Marsden

Prediction of node negative status by MRI = 28/31

Pathology stage MRI stage Total

pT0N0 1 (1 - mrT0N0) 1

pT1sm2N0 3 (3 - mrT1sm2-3N0) 3

pT1sm3N0 2 (2 -mrT1sm3N0) 2

pT2N0 13 (9 – mrT1sm3-T2N0; 4 – mr>T2N0) 13

pT3aN0 5 (5 – mrT3a-bN0)1 (1 – mrT3aN0) 6

pT3cN0 2 (2 – mrT3bN+)1 (1 – mrT3bN+) 3

pT3N0 3 (mrT3a-bN0/+) 3

The Royal MarsdenPrediction of node positive status = 10/13

Pathology MRI stage Total

pT1sm3N+ 1 (1 – mrT2N+) 1

pT2N+ 5 (2 – mrT2N+, 1 – mrT3bN+, 2 -mrT2N0) 5

pT3aN+ 1 (1 - mrT2N0) 1

pT3bN+ 3 (3 – mrT3bN+) 3

pT3cN+ 1 (1 – mrT2N+) 1pT3N+ 1 (1- mrT3bN+) 1pT4N+ 1 (mrT3bN+) 1Total 10 13

The Royal Marsden

According to the first scenario where MRI identified a >1mm boundary between the submucosa and muscularis: the sensitivity was 94% (95% Cl: 83%-98%) and accuracy was 89% (95% CI: 79-95%) . For the second scenario with the full thickness plane MRI identified a safe boundary of >1mm muscularis preserved with a sensitivity of 85% (95% CI: 0,61-0,96) and an accuracy of 89%(95% CI: 79-95%).

The Royal Marsden

Size and volume of metastatic disease in early rectal cancer

The Royal Marsden

Post TEMS and local excision for rectal lesions

• No evidence to indicate that lymph nodes rather than EMVI or local recurrence in the mesorectum are the primary cause of relapse following TEM

• Old data from TEM did not document outcomes in relation to MRI rather than clinical surveillance.

• Time to relapse, ideal follow up schedule and MRI appearances of early relapse? Absence of evidence.

• What is the long term prognostic importance of nodal micrometastatic disease versus EMVI – is a node containing a small focus of tumour ever viable in the long term – where is the evidence?

• Should histological evaluation of the resected polyp be used to drive the role of adjuvant chemoradiotherapy and chemotherapy in high risk T1 disease following local excision vs surveillance versus anterior resection?

The Royal Marsden

Morphology – flat semi-annularDiameter 16mmThickness of lesion : 7mmClockface location of central depression =4 oclockInvasive edge = 5mm diameterMuscularis fully preservedSubmucosa/muscle interface lost over 3mm distance on single slice at 4 o’clockLymph nodes show smooth nodal capsule and no heterogeneity - benignAssess height of 6.5 cm above anal verge and 12mm above puborectalis slingNo extramural venous invasionT1sm3/ with potential focal early T2 invasion on a single slice section1. APE/ELAPE2. Ultralow TME3. Local excision4. Full thickness TEM5. Preop Rx

The Royal Marsden

Final pathology• CLINICAL SUMMARY

TEMS-anorectal polypoid lesion 

• HISTOLOGY

The referred sections are of colonic mucosa with a tubulovillous adenoma having both highly and low-grade dysplasia, with an area of moderately to poorly differentiated adenocarcinoma with desmoplasia, tumour budding and focal mucinous differentiation. Invasive tumour area measures 13 x 5.5 mm and just involve the innermost fibres of the muscularis propria. There is lymphatic vascular invasion and focal submucosal venous angioinvasion. In therefore constitutes a higher risk lesion, although the nearest deep excisional or marginal clearance is 3.5 mm. Further deeper sections do not reveal any deeper invasion.

• pT2 NX MX LVI+ R0

The Royal Marsden

I/12 after TEM 3/12 after TEM

The Royal Marsden

5 years post Surveillance• She has been extremely well since her last review in the clinic. 

She is able to manage a normal diet and her weight is stable. • She refers to mild incontinence for gas and stool but denies any

blood or mucous in the stool.• On examination today, the abdomen was soft, non tender. 

There was no palpable lymphadenopathy.  On PR examination, the sphincter tone was mild.  There was no palpable mass in the rectum.

• There was no blood or stool on the gloved examination finger.  The CEA on the 11th February was 3 and the CA19-9 was 3.

• The last MRI showed no evidence of recurrent disease.

The Royal Marsden

Local excision scar

The Royal Marsden

Overall 44 patients (68%) underwent radical surgery, in 15 patients out of those 44 MRI had accurately identified T2N0 or less disease.

If the decision had been made to offer local excision on MRI TN staging rather than clinical assessment a significant increase in organ preservation surgery from 32% to 53% would be observed (difference 21%, CI 95%: 4.5% to 37%).

28/34 had 1 or more high risk features22/24 patients with low tumours and high risk features which would have required APER have so far avoided radical surgery and remain disease free at a median follow up 3.2 years. Lesions identified on MRI – roadmap for TEM/TAMIS: LEAssess mesorectum and TEM planesReview histologyCounsel patients: completion TME surgery versus adjuvant CRT and surveillance

The Royal Marsden

Recurrence after TEM

The Royal Marsden

The Royal Marsden

Discontinuous extramural venous spread – a poor prognostic factor

The Royal Marsden

The Royal Marsden

The Royal Marsden

MRI indications in ERC• To assess any polyp >5mm thick • Initial assessment of disease remote from the lumen within entire

mesorectum• Identification of pelvic sidewall disease• Road-mapping for surgical planning – identify site location of stalk

or invasive border and relationship to puborectalis sling, peritoneal reflection, mesorectal or intersphincteric border

• Identification of high risk patients with extramural venous invasion• Ongoing surveillance of high risk cancer patients opting for

conservative approach

The Royal Marsden

Minstrel Trial

The Royal Marsden

MINSTREL trial

The Royal Marsden

MINSTREL trial

The Royal Marsden

MINSTREL eligibility• Radiologists at recruiting sites will be trained and hold delegated responsibility • Eligible patients will be identified on colonoscopy if they are found to have a

20mm to 50mm rectal tumour within 150mm of the anal verge (consent and completion of endoscopy CRF)

• All patients who enter the trial will be sent for an MRI. The MRI will be reported using the novel staging proforma (radiology CRF)

• The patients will proceed to excision or resection of the tumour as per clinician / MDT discussion. (MDT CRF)

• The appropriateness of preoperative stage will be compared against histopathology gold standaed (Pathology CRF)

The Royal Marsden

Primary Endpoint• To determine if there is a difference between the

percentage correct allocation of clinical and MRI assessment of rectal lesions.

• Trial to open in 2015: 55 patients needed to show a 30% improvement compared with conventional assessment in staging for correct excision plane using MRI reporting system

The Royal MarsdenRecommendations: staging accuracy is dependent on technique

Low ResolutionField of view 22 x24cmVoxel size: 1.6mm3

The Royal MarsdenMERCURY protocol scan – same patient 1 week later

High ResolutionField of view 16 x 16cmVoxel size: 1.1mm3

The Royal Marsden

75 yr old male• PS1• Colonoscopic detected polyp

The Royal Marsden

Treatment plan: scenario 1• EUS reports: at least T1

Options:• TME• Repeat biopsy• Preoperative RT/CRT• TEM

The Royal Marsden

The Royal Marsden

The Royal Marsden

MRI Report

The Royal Marsden

Histopathology report

The Royal Marsden

MDT discussion of Imaging and pathology

The Royal Marsden

The Royal Marsden

Patient decision

The Royal Marsden

The Royal Marsden

Conclusions• Early stage tumours can be usefully evaluated using high

resolution MRI and high frequency ultrasound for superficial lesions

Technique important Options to consider especially for low lying early stage tumours:

results from current trials awaited Follow up if less radical therapy is given: MRI surveillance is

important to enable early detection of salvageable regrowth/recurrence

RECTAL MRI INTENSIVE TWO DAY WORKSHOP

WITH HANDS ON WORKSTATION PRACTICE FOR RADIOLOGISTS, SURGEONS AND ONCOLOGISTS

Euston House

24 Eversholt Street London NW1 1AD

Aims: This course enable will equip you to ensure high quality MRI in your institution and to be able to evaluate baseline and post treatment MRI assessment of rectal cancer and pelvic anatomy with confidence for your daily practice.

Day One Will provide you with essential knowledge for MDT working and MRI assessment in different clinical scenarios with details revision of anatomy and interpretation criteria as a preparation for Day Two.

Day Two Will give you hands on workstation practice for assessing rectal cancer cases and pelvic anatomy and how this is applied to treatment planning. For teams participating in MINSTREL, TRIGGER AND STARTREC trials, you will be certified as having sufficient training to take delegated responsibility for trial participation.

PROFESSOR GINA BROWN

Registration Form Name: Position: Institution:

The information above will appear on your badge for the course email: Tel:

Address:

I wish to register for (please tick as appropriate):

Course Code M00117 30th 31st January 2017 Full 2 day course, 30th 31st January £550 early bird

Booking after 29th December: £650 Day One only, 30th January £300 Day Two only, 31st January £350

Course Code M0317 30th 31st March 2017

Full 2 day course, 30th 31st March £550 early bird Booking after 28th February: £650

Day One only, 30th March £300 Day Two only, 31st March £350

Course Code M0617 8th 9th June 2017

Full 2 day course, 8th 9th June £550 early bird Booking after 7th May: £650

Day One only, 8th June £300 Day Two only, 9th June £350

Course Code M0917 28th 29th September 2017

Full 2 day course, 28th 29th September £550 early bird Booking after 27th August: £650

Day One only, 28th September £300 Day Two only, 29th September £350

Please return registration form to Gina.Brown@rmh.nhs.uk or Fax: + 44 (0) 20 8915 6721 You will receive confirmation of your registration within 2 working days together with an invoice and instructions for payment. Without written confirmation your booking is not valid, without payment your place is not guaranteed.

Please contact +44 (0) 20 8661 3964 if you have any queries

REVISE TIPS AND TRICKS FOR:

Pelvic applied anatomy assessment skills

MDT based working

MRI rectal cancer interpretation skills

Case discussions and controversies

Rectal cancer scanning standards

Hands on workstation cases with live feedback and

course booklet

Registration

Two day workshop combined cost (early bird)) £550 Day One only MDT working and revising the MRI interpretation £300

Day Two only Workstation practice, self-testing with answer booklet and notes £350 Price includes lunch and refreshments for each delegate on both days. Capacity is limited so to guarantee your place, please complete the registration section of this flyer and return as soon as possible

11 CPD points applied for