An Overview of Ulcerative Colitis and Colon Cancer
About 5 percent of people with ulcerative colitis
go on to develop colon cancer
. The risk of cancer increases with the length of time and how much of the colon
is affected by ulcerative colitis (the more colon involved, the greater the risk). For example, if only the rectum is involved (known as ulcerative proctitis) or the lower colon and rectum are involved, the risk of cancer is no higher than normal. However, if the entire colon is involved, the risk of cancer may be as much as 32 times the normal rate.
Ulcerative Colitis and Colon Cancer: Recommendations
Sometimes precancerous changes occur in the cells lining the colon. These changes are called "dysplasia." According to the 2002 updated guidelines for colon cancer screening
, people who have had an inflammatory bowel disease (IBD) like ulcerative colitis throughout their colon for at least 8 years, and those who have had IBD in only the left colon for 12 to 15 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 in its early stages, should it develop. These guidelines were produced by an independent expert panel and endorsed by numerous organizations, including the American Cancer Society, the American College of Gastroenterology, the American Society of Colon and Rectal Surgeons, and the Crohn's & Colitis Foundation of America Inc., among others.