mri of rectal cancer - puzzlepix · mri of rectal cancer dr damian tolan consultant...

MRI of Rectal CancerDr Damian Tolan

Consultant Gastrointestinal RadiologistLeeds Teaching Hospitals

Hungarian Congress of Radiology June 2016

1. What are we doing this scan for?

2. How to get a good scan

3. What should we say?

How I report MRI of rectal cancer

1. Radiologists are now key members of a BIG multidisciplinary team.

2. There are a lot of people to cater for…

What are we doing this for?

We need to cater for a lot of tastes� Does the patient need an operation?

� What type of operation?

� Do they need Preoperative treatment?

� Radiotherapy

� Chemotherapy

� both?

What are we doing this for?

We are like Chefs

� We must use only the best ingredients

� We should always produce digestible food

� The meal should be the same every time…which ever chef is cooking!

What is our job?

What kind of Chef do you aspire to be…?

Because…

There are Chefs…

A Muppet…

� Variable� Good days and bad

days� Irratic

and there are Chefs…

Ferran Adria… 3 Michelin Stars

� Consistent� High standards� Reproducible work

OR ?

Our aim?

The best ingredients

Budapest Market this morning!

� Good quality MRI is essential to a good report

� The key components…� Phased array body/pelvis coil

� Adequate coverage

� High resolution/small field of view

� Thin slices (3mm)

� Angulation

The best ingredients

Brown Radiology 2003

Orthogonal and perpendicular to the tumour

� Why?

TO ANSWER THE KEY QUESTIONS

� How far has tumour penetrated?

� What is the relationship to the circumferential resection margin?

Angulation

Imaging planes - orientation

• Sagittal allows planning

Angulation - low


• Inclined axial sphincter invasion

Angulation - low

nb. white = mucinous = worse prognosis


• Inclined coronal relationship to levator

Angulation - low

nb. white = mucinous = worse prognosis

Imaging planes – orientation

• Sagittal for planning coronal to assess side wall

Angulation - mid

Imaging planes – orientation

• Sagittal for planning axial – relation to mesorectum

Angulation - upper

Remnant of embrylogical hindgut mesentery

Contains:

� Rectum

� Fat

� Lymph nodes

� Vessels

This is resected complete in a Total MesorectalExcision (TME)

This boundary becomes the Circumferential Resection Margin (CRM)

Mesorectal fascia?

Mesorectal Fascia and CRM

Mesorectalfascia

Total Mesorectal Excision

Nagtegaal et al. JCO 2002Removed intact

TNM stage of the tumour predicts outcome

TNM stratifies benefit from neoadjuvanttherapy

What is the relevance of staging?

T1 - tumour invasion into submucosa

Muscularis propria not invaded

T staging


Muscularis propria not invaded

T staging

Cancer within large pedunculated tubulovillous adenoma


�These patients may be offered local resection

(Transanal Endoscopic MicroSurgery – TEMS)

T staging

Muscularis propria

Focus of invasive cancer in TVA

MucosaSubmucosa

T2 – tumour invasion into muscularis propria

Muscularis invaded (not beyond)

T staging


Muscularis invaded (not beyond)

T staging

Tumour cannot be distinguished from muscularis


�Usually straight to surgery

T staging

Tumour cannot be distinguished from muscularis

T stagingT3- invasion beyond muscularis propria

Mesorectal

fascia invaded by

tumour

Muscularis completely replaced

T3 tumours – ‘the GOOD’T staging

T3b 1-5mm

T3a<1mm

Muscularis propria

MERCURY study group Radiology 2007

T3 tumours – ‘the GOOD’� May go straight to surgery� Short course radiotherapy if other

adverse features � E.g. positive nodes or extramural vascular

invasion

T staging


T3 tumours – ‘the BAD’T staging

T3(any) & threatened CRM

T3c 5-15mm

T3d>15mm

1mm or less

(tumour to mesorectal

fascia)

Mesorectal fascia


Mesorectal Fascia and CRM

Tumour involving or within 1mm of the MRE is a strong predictor for local recurrence

If you see it you MUST say it! Tumour in contact with CRM

12-1 o’clock

T3 tumours – ‘the BAD’� Usually offered

Chemoradiotherapy beforesurgery

T staging


T4 - invasion of adjacent structures

� Peritoneum

� Viscera

� Pelvic sidewall

� Sphincter / pelvic

floor

T staging

T4 - invasion of adjacent structures

� Given neoadjuvantCRT

� Likely positive resection margin unless it is resected

(E.g. an organ or peritoneal resection)

T staging

Nodal disease� Size not a useful discriminator� Shape important -irregular border� Internal architecture -mixed signal

intensity

N stage

Brown et al Radiology 2003

Nodal disease� When either or both are present (even

in small nodes)� Sensitivity 85%� Specificity 97%for malignancy

N stage

Brown et al Radiology 2003

Mesorectal nodes� Relationship to CRM not so important

� Positive nodes within 1mm of CRM not strong predictor of local recurrence (vs. direct tumour spread)

� Main risk is 4 or more nodes (N2)

N stage

Shihab et al Br J Surg 2010

Pelvic side wall nodes� Not in a usual surgical resection� Can be targeted with a ‘boost’ of

radiotherapy � Difficult to identify when

laparoscopic resection (or even open)

� Not an independent prognostic factor (cf primary tumour features)

N stage

MERCURY Study Group Br J Surg 2011

Don’t ‘over call’ nodes� only call those that are definitely

abnormal� +ve nodes at the CRM do not have

the same implication as direct tumour

N stage

Extramural vascular invasion� Present in up to 50% specimens� Poor prognostic factor� Increases risk of distant

metastasis and pelvic side wall nodal disease

V stage

Smith et al AJR 2008

Linear tumour extension along vessels

V stage

Can pick up more subtle invasion with care

V stage

Mucinous differentiation = white tumourconsider adding T1 axial (helps with spotting nodes

Other features

Mucinous differentiation = white tumourconsider adding T1 axial (helps with spotting nodes)

Other features


Reporting Proforma:Should we all be saying the same thing?


Reporting Proforma:Should we all be saying the same thing?WE WILL BE SOON…

� Know how TNM relates to patient care� Prepare well (angulation & resolution)� Don’t leave any ingredients out

(T, N, V, CRM status, M-)� Use the same recipe EVERY TIME

Conclusion

To my all my Colorectal MDT colleaguesColorectal Surgery: Sagar, Jayne, Botterill, Burke, Saunders, Baker, Hance, Maslekar, RiyadClinical Oncology: Sebag-Montefiore, Radhakrishna, Casanova, CooperMedical Oncology: Seymour, Anthoney, Swinson, HookPathology: Scott, Rotimi, West

Especially to my fellow Chefs (Radiologists)!Rachel Hyland, Hannah Lambie, Tom Kaye, Elen Thomson

Finally, thanks…

mri of rectal cancer - puzzlepix · mri of rectal cancer dr damian tolan consultant...

Documents