Myosarcomas of the small and large intestine: a clinicopathologic study.

A retrospective study was made of 38 myosarcomas of the small and large intestines (34 leiomyosarcomas and 4 malignant leiomyoblastomas). Endoenteric, small, and noninvasive tumors were successfully treated by simple wedge excision, cautery snare removal, or segmental bowel resection with a high 5-yr cure rate of 86% (12/14). Exo-enteric tumors often invaded adjacent structures or perforated into the peritoneal cavity. Extensive resection procedures, including pancreaticoduodenectomy, abdominoperineal resection, and pelvic exenteration salvaged only 13% (2/16) of these patients. Three clinicopathologic factors adversely affected prognosis: i) tumor size greater than 5 cm in diameter, ii) extra-intestinal invasion or free perforation, and iii) high histopathologic grade of malignancy. The presence of none, one, two, or three of these adverse factors gave decreasing 5-yr survival rates of 100, 44, 31, and 0%, respectively. These observations suggest use of a multimodal treatment program that may minimize treatment failure from local as well as distant disease.