The dramatic presentation of colonic lipomata: report of two cases and review of the literature.

Colonic lipoma with a dramatic presentation requiring urgent operation is a rare occurrence. We report two such cases in conjunction with a review of the literature on colonic lipomata. Clinicopathologic features of two patients who required urgent resection were studied. The preoperative diagnosis of colonic lipoma was suggested on imaging study in one case. A MEDLINE search was conducted with a special goal of revealing cases with a dramatic presentation. One patient presented with rectal bleeding and intussusception related to a partially infarcted 4.5-cm submucosal lipoma of the lower descending colon. The second patient presented with intestinal obstruction related to a near-totally infarcted 6-cm submucosal lipoma at the splenic flexure. In both cases a florid reactive vascular and fibro-/myofibroblastic proliferation and associated hyperplastic mucosal pattern were present at the base and edge of the lipoma. Among 275 previously reported cases of colonic lipoma 28 patients had a dramatic presentation with pain and/or rectal bleeding being the most significant prodromal symptom. In this subset the lipomas tended to be larger, frequently had associated marked necrosis/ulceration, and were less likely to be located in the ascending colon/cecum. Whereas colonic lipomas are relatively common occasional cases present dramatically with massive bleeding, intussusception, or even perforation for which emergency operation is required. Such lipomas usually reveal marked ischemic changes.