[Ascending colon cancer with submucosal tumor-like morphology arising near ileal valve lipohyperplasia:a case report].

An 89-year-old man was diagnosed with a submucosal tumor suspected to be a lipoma and was followed up for 6 years. The patient was admitted to the hospital because of increased tumor size and morphological changes despite negative bioptic findings. The lesion was diagnosed as an advanced adenocarcinoma of the ascending colon (cT3N0M0, cStage IIa). Laparoscopic-assisted right hemicolectomy with D3 lymph node dissection was performed. Pathological diagnosis of a surgically resected specimen revealed adenocarcinoma with lipohyperplasia (pT3N2aM0, pStage IIIb). Reports of colon cancer accompanied by colonic lipomas or lipohyperplasia are limited. This case showed an interesting submucosal tumor-like morphology because the cancer developed at the base of the lipohyperplasia and grew and spread below it.