For people with ulcerative colitis, there are two factors affecting the risk of developing colon cancer:
- Risk increases after 8 to 10 years of having ulcerative colitis.
- Patients with disease only in the rectum have the lowest risk, and having only part of the colon involved carries an intermediate risk.
For people with any form of IBD:
- The risk of colon cancer for people with IBD increases by .5 to 1.0% yearly 8 to 10 years after diagnosis.
- People with IBD may be as much as five times more likely to develop colon cancer than people who do not have IBD.
- People whose IBD has been quiet have the same risk as those who have more active disease.
