Considerations of surveillance, dysplasia, and carcinoma of the colon in the management of ulcerative colitis and Crohn's disease.

Patients with ulcerative colitis are at greater risk of developing carcinoma of the colon than the general population even if the exact risk cannot be determined. Thus, an effort must be made to find the carcinoma at its inception or better still before it occurs. Dysplasia serves as a premalignant marker in some cases, and a surveillance program serves to find either dysplasia or the carcinoma. Until more specific premalignant changes are identified, endoscopic surveillance with multiple biopsies offers the best protection for the patient with longstanding ulcerative colitis against carcinoma. There is now sufficient evidence that this also pertains to Crohn's disease of the colon.