Superior mesenteric vein tumour thrombus in a patient with caecal adenocarcinoma: a rare and important finding.

Venous tumour thrombosis refers to the invasion of tumour into the venous system. Extramural venous invasion is routinely searched for and reported in rectal carcinoma due to its prognostic significance and influence on staging, prognosis and treatment approach. We describe a case of extramural venous invasion occurring as superior mesenteric vein tumour thrombus in the setting of a caecal carcinoma.