Rectal adenocarcinoma with peritoneal and omental metastases

Case contributed by Vikas Shah
Diagnosis certain

Presentation

Rectal bleeding and weight loss. History of ulcerative colitis, no previous colonic surgery. Malignant looking rectal mass identified and biopsied at endoscopy. Staging MRI requested.

Patient Data

Age: 65 years
Gender: Male

There is extensive rectal and peritoneal malignancy with multiple adverse features.

The lowest portion of the circumferential tumor is 5 cm from the anal verge, and extends over a length of approximately 12 cm, from the lower rectum up to the sigmoid.

There is unequivocal infiltration through the muscularis propria. Anteriorly, the tumor infiltrates the anterior mesorectal fascia. The tumor has penetrated into the peritoneal reflection with gross peritoneal thickening noted.

There are multiple heterogenous mesorectal nodes and nodes along the draining vascular pedicle. There is evidence of EMVI.

Radiological staging is T4, N2, M1, EMVI positive, CRM involved

 

There is free fluid in the upper abdomen. No suspicious parenchymal liver lesion on these sequences, but there is evidence of subcapsular metastatic disease and extensive peritoneal and omental nodularity.

Case Discussion

Recent publications have underlined the importance of extramural vascular invasion (EMVI) as a predictor for metastatic disease, and this feature should be searched for carefully on MRI to aid in risk stratification.

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