The patient had a known history of a caecal tumour, and was awaiting surgery. Intussusception in older patients almost always has a pathological lead point. This patient proceeded to a right hemicolectomy.
MACROSCOPIC DESCRIPTION:A right hemicolectomy with terminal ileum, large bowel, appendix, mesentery and omentum. Within the caecum, immediately adjacent to the appendiceal orifice and 35mm from the ileocaecal valve is an ovoid rubbery brown tumour which invades 5mm deep into muscularis propria and is 2mm from the serosa which is shiny and smooth. The proximal 110mm of large bowel has oedematous mucosa and a wall up to 10mm. The mesentery contains numerous rubbery tan lymph nodes up to 18mm. The omentum is unremarkable.
MICROSCOPIC DESCRIPTION: Sections of bowel show a moderately differentiated adenocarcinoma focally invading through muscularis propria into subserosa. Tumour comprises cribriform glands and nests of atypical columnar cells within fibrotic stroma. There is a prominent peritumoural Crohnoid lymphocytic infiltrate. Stromal clefting around tumour nests is present but lymphovascular and perineural invasion are not seen. Tumour is clear of serosa, margins and appendix. The caecum shows an area of marked submucosal oedema, consistent with an area of intussusception. The omentum is unremarkable. There are twenty four lymph nodes with no evidence of malignancy.
DIAGNOSIS: Moderately differentiated adenocarcinoma, arising within caecum.