Inflammatory Bowel Disease and Cancer Risk - Topic Overview
Inflammatory bowel disease (IBD)
increases the risk of colon cancer. The amount of increased risk depends on the
type of inflammatory bowel disease (ulcerative colitis or Crohn's disease of
the colon), how much of the intestine is involved, and how long you have been
ill. The cancer risk usually does not increase until you have
had IBD for 8 years or longer.
Starting 8 years after diagnosis,
most doctors recommend screening for colon cancer every 1 to 3 years. The type
of screening depends on the extent of IBD. For people with ulcerative colitis
that affects only the rectum (proctitis), the increase in cancer risk is
slight. In those cases, some experts feel that screening is not needed. But
sigmoidoscopy sometimes can be used.
Colonoscopy is needed if more of the colon is
involved. The doctor will take small tissue samples (biopsies) in the area
affected by IBD to check for precancerous changes or cancer. If abnormal tissue
is found, surgery may be done, usually to remove the colon (colectomy).
With appropriate screening, some cancers are found early and are
The risk of cancer increases the longer a person
has colitis of the entire colon.