Prevention of cancer at the urothelial enteric anastomotic site.

An animal model of ureterosigmoidostomy was employed to elucidate the etiology of urinary intestinal anastomotic cancer. One hundred ninety-four rats were divided into five groups: vesicosigmoidostomy rats fed water without drug (controls); those fed ammonium chloride, or sodium bicarbonate, or ascorbic acid; and, finally, vesicosigmoid interposition rats. A significantly decreased incidence of cancer was evident only in the bowel interposition group (p less than 0.001). Ascorbic acid and altered urinary pH were not prophylactic. Possible mechanisms are discussed.