Granular cell myoblastoma of the sigmoid colon.

A granular cell myoblastoma of the upper sigmoid colon is reported in a 53-year-old male. The tumor was detected during investigation of abdominal pain and was removed by colonoscopic polypectomy. Colonoscopy provides a new method of treatment for these unusual colonic lesions and avoids the need for surgery. To our knowledge the tumor has not been reported previously in the sigmoid colon.