about 5% of people with ulcerative colitis develop colon cancer. the risk of cancer increases with the duration of the disease and how much the colon has been damaged. sometimes precancerous changes occur in the cells lining the colon. these changes are called "dysplasia. " people who have dysplasia are more likely to develop cancer than those who do not. according to the guidelines for colon cancer screening people who have had inflammatory bowel disease in at least one-third of their colon for at least eight years should have a colonoscopy with biopsies every one to two years to check for dysplasia. such screening has not been proven to reduce the risk of colon cancer but it may help identify cancer early.
is colon cancer a concern with ulcerative colitis?