Ulcerative colitis, autoimmune epiphenomena, and colonic cancer

Abstract

The risk of developing a carcinoma of the colon is clearly increased in patients with ulcerative colitis. The basis for this relationship, however, is unknown, since the pathogenesis of both the predisposing colitis and the complicating carcinoma remain undefined. Most recent studies have attempted to implicate some type of immune response in the etiology of ulcerative colitis. Humoral antibodies to a colonic epithelial cell antigen have been demonstrated but are of doubtful significance. Perhaps of greater potential importance is the presence of circulating lymphocytes that are cytotoxic for colonic epithelial cells. These immune phenomena per se, however, probably bear no direct relationship to neoplasia since: 1) they occur in granulomatous colitis where the incidence of carcinoma is far less; 2) cell mediated immunity (immunologic surveillance) is intact in ulcerative colitis but depressed in granulomatous colitis; and 3) similar immune phenomena are not present in patients with colon cancer without inflammatory bowel disease. Copyright © 1974 American Cancer Society