peritoneal spread risk in gastric, pancreatic and colon cancers

Peritoneal spread risk in Gastric , Pancreatic and Colon cancers

www.slideshare.net/GinaBrown3

Understanding patterns of failure

• Improvements in surgical technique• Identification of subgroups benefiting from

preoperative therapy• Refine radiotherapy Rx volumes• Primary endpoint of rectal cancer trials

Predictable patterns of recurrence

• Tumour spillage• CRM involvement• Peritoneal perforation• Distal margin involvement• Residual disease

Space of Retzius

Bladder

mesorectum

rectum

peritoneal

peritoneum

Mesorectal fascia

Post surgical pelvis

Post TME pelvis

Marginal pattern of recurrence

Starling, Scott-Mackie, Brown et al 2005

CRM involvement and later recurrence

Marginal recurrence

Anastomosis

Anastomotic recurrences

Tumour spillage

Perineal recurrence

Perineal

Hydronephrosis = strong likelihood of local recurrence

Brown et al Clinical Radiology 2003

75 patients, new hydronephrosis is a predictor for peritoneal recurrence (90% of patients).

Peritoneal perforation

Distal margin involvement

Nodal recurrence

Nodal recurrence

Krukenberg Tumours

Relapse Pattern No of Patients n=70

(a) Marginal (around the margins of the surgical bed)

43.9%

(b) Lymph node (internal or external iliac groups)

24.3%

(c) Pelvic peritoneal 22.0%

(d) Perineal 14.6%

(e) Anastomotic 12.2%

(f) Krukenberg 2.4%

• MDT 2007-09• 296 sigmoid cancers • 104 for palliative care

• Curable sigmoid cancers: n=192• No FU data at all: n=42• With FU: n=150• FU 36 months (range 1-76, median 38)

• Recurrence: 62/192 (32%) • Local recurrence: 19 (11%)

Recurrence sigmoid cancer

High risk features

• Tumour involving non peritonealised fascial margin

• Tumour penetration of adjacent organs• 4 or more involved nodes• Extramural venous invasion• Depth of extramural spread >5mm

Eur J Surg Oncol. 2005 Oct;31(8):845-53.

Improved survival

Are we able to preoperatively identify poor prognostic features in colon cancer?

Burton 2006 Int. J. Radiation Oncology Biol. Phys

• Primary surgery n=57

• 16 at/above peritoneal reflection

• 19 rectosigmoid• 22 sigmoid

• Neoadj CRTx + surgery n=18

• 9 at/above peritoneal reflection

• 5 rectosigmoid • 4 sigmoid

Burton 2006 Int. J. Radiation Oncology Biol. Phys

MRI predicted prognosis with final histological prognosis in 57 patients undergoing primary surgery

Final histological prognosis

Good Poor TotalMRI Good 31 6 37

PredictedPrognosis Poor 10 11 21

Totals 41 17 5884% (CI =72.6-92.7%) accuracy for MRI prediction of prognosisKappa = 0.63Sensitivity = 90%Specificity = 72%Positive predictive value = 88%Negative predictive value = 76%

Burton 2006 Int. J. Radiation Oncology Biol. Phys

Diagnostic dilemmas – is it recurrent disease or not?

• Mass - ? Significance• Scar vs recurrence• PET-ve• Inflammatory collection vs recurrence

New Mass

Examples of reporting criteria

Importance of baseline review

2004 2000

Peritoneal pelvic recurrence

Scar vs Recurrence

Collection vs Recurrence

PET-ve

Anatomical information – to plan resection/resectability

• Which compartment?• Which sacral level?• Multifocal vs unifocal – High res MRI

essential• Distant metastases, review of both contrast

enhanced MDCT and CT-PET helpful• Trial of chemotherapy/RT prior to radical

surgery – response assessment

Operation likely? – yes/ probably no

• Yes:– Central compartment– Anterior compartment

below peritoneal reflection

– Posterior compartment below S2

– Perineal

• Probably no:– Lateral compartment– Sciatic nerve infiltration

(coronal imaging)– S1/S2 sacral infiltration– Peritoneal perforation

Post TME pelvis

Central compartment

Post Chemo

Lateral compartment

Key messages

• Know patterns of recurrence• Familiarity with post surgical pelvis• FDG PET-CT helpful tool • Growing mass on CT/MRI with elevated CEA =

diagnostic of recurrence

Conclusions

• GI Radiologists now play a key role in the MDT for detecting and selecting patients with recurrent disease for radical treatment– Aggressive imaging based follow up of high risk

patients results in earlier detection increases survival

– Anatomic delineation and characterisation of lesions using both MDCT/MRI with contrast

– Careful use of multimodality imaging in assessing extent of disease (PET/MRI/CT)

Gastric cancer risk factors

• Published evidence – clinico pathological risk features

• Imaging assessment of gastric cancer• Delineation of the primary tumour• Nodal disease versus extranodal disease and

its depiction on CT

Pancreatic cancer

• T4 and transperitoneal seeding– Known Mechanisms of transperitoneal spread in

pancreatic cancer and rates of PC– Lymphatic– Vascular– Implantation and seeding

For the group to develop in future:

• More work in determining imaging features at baseline for peritoneal relapse T category is too broad and crude a tool

• Improve documentation of tumours at baseline and compare against outcomes

• Patterns of spread are key• Proforma reporting and consistent

documentation at diagnosis and at relapse is essential