Ulcerative colitis, particularly when there is total colonic involvement, is a premalignant lesion of the colon. We review the available methods for the early detection and prevention of colonic carcinoma in patients with ulcerative colitis. These methods include detection of precancer (carcinoma in du) in rectal and colonic biopsies, with and without immunoperoxidase staining for carcinoembryonic antigen; detection of penirtently elevated serum carcinoembryonic antigen; roentgenologic detection; colonoscopic detection; ?to- logic detection; and simple recommendation of total colectomy in all patients with continuously active, extensive colitis after 10 years of disease. Currently, of these methods available, only detection of precancer (carcinoma in sihr) in rectal and colonic biopsies holds promise for the early detection of colonic carcinoma, and there are many pitfalls with this method. Precancer, when analyzed in total colectomies, is absent in 12% of patients with carcinoma complicating ulcerative colitis and is found in the rectum in only 66% of these patients. Thirteen percent of patients with severe ulcerative colitis requiring colectomy have precancer in the absence of cancer. Precancer, when analyzed in rectal biopsies of patients with ulcerative colitis, is found in 5.7% of the patients. Thirty-two percent (17/53) of those patients with precancer in rectal biopsy were found to have colonic carcinoma, while two-thirds of these patients did not have colonic cancer. The role of colonoscopy at regular intervals with the collection of multiple biopsies throughout the colon is currently being evaluated in hopes that this method will more accurately and consistently permit early detection of precancer and cancer in patients with ulcerative colitis of 10 or more years' duration.
Cancer 40:2542-2548, 1977.
T IS NOW WELL ESTABLISHED THAT THE PREVA-I lence of colonic carcinoma in patients with ulcerative colitis is approximately 3-5%. 'A'*'* B~l'~"*''~ss When compared with the incidence of cancer of the colon and rectum in the general population, the risk of cancer in patients with ulcerative colitis is more than twenty times greater. Truelove has distinguished four factors that may be recognized early in the course of ulcerative colitis and that are associated with a high risk of subsequent develop-