Prolapsing mucosal fold: largest reported, presenting with major haemorrhage.

Prolapsing mucosal folds are uncommon benign colonic lesions that when inflamed may macroscopically resemble, and be confused with, an adenomatous or hyperplastic polyp. They are usually small and rarely cause symptoms. We report the case of a 55-year-old female admitted to hospital following six episodes of significant rectal bleeding. A colonoscopy revealed a 45 × 12 × 5 mm3 pedunculated polyp in the sigmoid colon. There was no evidence of haemorrhoids, colitis or diverticulosis. The polyp was resected by electrosurgical snare at 40 cm and a resolution clip was used to prevent postoperative bleeding. Histology of the polyp demonstrated a polypoid prolapsed mucosal fold with a core of fibrovascular submucosal tissue and normal overlying mucosa. In an extensive review of available literature, no polyp of this size has been reported.