Benefits of endorectal ultrasound for management of smooth-muscle tumor of the rectum: report of three cases.

Smooth-muscle tumor of the rectum is rare, and the therapeutic strategy is still controversial. Endorectal ultrasound was used to evaluate three patients with smooth-muscle tumor of the rectum. Endorectal ultrasound demonstrated a homogenous hypoechoic tumor without invasion to the perirectal tissue in two patients. The tumor was 5 cm in diameter in one patient and 4 cm in diameter in the other patient, and they were excised locally. Their histologic types were leiomyoma and leiomyosarcoma. The third patient had a recurrent leiomyosarcoma. Proctosigmoidoscopy found a linear lesion with ulcerated mucosa on the rectal wall. Endorectal ultrasound observed a hypoechoic solid tumor of 3.5 cm x 1 cm, which involved the mucosal, submucosal, and muscle layers of the rectal wall. Disruption of the first hypoechoic layer was identified. Abdominoperineal resection was performed. Endorectal ultrasound follow-up revealed no evidence of recurrence in any of these patients. Endorectal ultrasound can help to define the extent of disease and may be a useful adjunct in deciding about the appropriate surgical procedure in these diseases.