Surveillance colonoscopy and biopsy in patients with ureterosigmoidostomy.

Colonoscopy with biopsy was included in the surveillance of 19 patients with ureterosigmoidostomy, because of the high incidence of colonic carcinoma reported in such cases. The patients were examined 1-6 times, at intervals of 1-2 years, 4-36 years after the urinary diversion. Random biopsies from the distal colon and rectum showed only discrete changes, and no dysplasia. Polyps with dysplastic changes were found close to ureteral anastomoses in three patients. For routine check-up of the rectosigmoid region and the ureteral implantation sites, examination with a flexible sigmoidoscope seems to be adequate and preferable, giving easy access to the risk zone for the development of cancer. Caution should be exercised, however, when performing biopsy close to the ureteral orifices.