Cancer surveillance after ureterosigmoidostomy: colonic microscopic changes.

Ureterosigmoidostomy (U-S) is a procedure for diversion of the urinary stream. U-S is associated with a manyfold-increased risk for subsequent development of colonic carcinoma close to the sites of ureteral entry into the sigmoid colon. A surveillance program for colonic carcinomas in U-S patients includes colonoscopic examination of the colon to at least 60 cm and random biopsies of the sigmoid colon distal to the ureteral orifices. In eight patients, a change from sulphomucin to a variable admixture with sialomucin was found in the histologically unremarkable colonic mucosae. When the urinary stream was shunted away from the U-S site in two patients, the mucosal mucin was composed of sulphomucin which is present in normal sigmoid colons. The effect of urine admixed with feces in the sigmoid colon is nonspecific as judged by alterations of the mucosal mucin composition. The U-S patient deserves periodic examinations to detect colonic carcinoma but the histological examination of colonoscopically unremarkable mucosae is not currently contributory toward this surveillance effort.