Ulcerative colitis and colon cancer.

Chronic ulcerative colitis is an idiopathic inflammatory disease of the colon associated with an increased incidence of colorectal cancer. Colonoscopy with biopsy for mucosal dysplasia (precancer) can identify individuals with ulcerative colitis who are at increased risk for colorectal cancer. Identification of high-risk individuals can be used to guide clinical decisions regarding the timing and appropriateness of prophylactic colectomy.