Carcinoma of colon after ureterocolic anastomosis: implantation on calyceal mucosa.

Two cases are reported of the development of mucoid adenocarcinoma of the colon in young patients, nineteen and thirty-four years after ureterocolic anastomosis for benign conditions. One patient showed implantation of the colonic neoplasm on the mucosa of an upper calyx in the obstructed kidney. Patients who have undergone ureterocolic anastomosis have a greatly increased risk of the development of large-bowel neoplasms. When suspected, radiologic examination of the colon using a water-soluble contrast material, together with rectosigmoidoscopy or colonoscopy, is essential. Because of the serious nature of this complication, it is suggested that the recent trend to return to the use of large bowel in urinary diversion may be hazardous, especially in the young patient with a benign disease.