A Case of Rectal Leiomyosarcoma Presenting as a Semipedunculated Polypoid Mass / 대한소화기내시경학회지

ABSTRACT

Rectal leiomyosarcoma is an extremely rare disease. Anal bleeding, rectal pain and a sensation of pressure in the anus are the most common symptoms. It tends to form a polypoid intraluminal mass and commonly originates from the muscularis propria, but may arise from the muscularis mucosa, or in the walls of the blood vessels. Characteristically, leiomyosarcoma has very high mitotic activity and is, on immunohistochemical staining, positive for actin and desmin, but negative for c-kit and S-100. We experienced a case of a rectal leiomyosarcoma in a 54 year-old man who presented with anal bleeding. Colonoscopic examination revealed a 4.5 cm-sized semipedunculated polypoid mass at mid-rectum. We confirmed that it was a leiomyosarcoma histologically by endoscopic resection with mechanical snaring. Low anterior resection followed by radiation therapy was performed. We report here on this case with a review of the relevant literature.