Colorectal cancer in inflammatory bowel disease.

Patients with long-standing inflammatory bowel disease have an increased risk of developing colorectal cancer (CRC). CRC risk increases with longer duration of colitis, greater anatomic extent of colitis, the presence of primary sclerosing cholangitis, family history of CRC and severity of inflammation of the colon. Chemoprevention includes aminosalicylates, ursodeoxycholic acid, and possibly folic acid. To reduce CRC mortality in IBD, colonoscopic surveillance remains the major way to detect early mucosal dysplasia. When dysplasia is confirmed, proctocolectomy is considered for these patients. Ulcerative colitis patients with total proctocolectomy and ileal pouch anal-anastomosis have a rather low risk of dysplasia in the ileal pouch, but the anal transition zone should be monitored periodically. New endoscopic and molecular screening approaches may further refine our current surveillance guidelines and our understanding of the natural history of dysplasia.