Leiomyosarcoma of the rectum.

Leiomyosarcoma of the rectum is a rare entity. Approximately 150 cases have been described in the literature. Differentiation from its benign counterpart, leiomyoma, and other connective-tissue tumors is often difficult, but it is important because each tumor has an entirely different prognosis. The case of a patient in whom an 11 x 5.5 cm leiomyosarcoma of the rectum was surgically excised by abdominoperineal resection is presented. Literature review shows disagreement over the therapeutic approach, most likely due to the lack of a large series of patients with this disease. At present, a selective treatment approach appears to be the most advocated. Lesions less than 2.5 cm in size and limited to the bowel wall can still be treated by wide local excision. More radical surgical resection is indicated for larger tumors and those extending outside the bowel wall.