Posted 5/8/2017 1:00 PM (GMT 0)
No, not all pancolitis patients get cancer. The statistics you are looking for can be found here: http://www.crohns.org.uk/ulcerative_colitis/cancer-and-ulcerative-colitis
One thing you need to remember is that those with IBD generally get screened for cancer FAR more often than the average person without IBD, which means that if cancer ever occurs, it is likely to be caught very early when it is still curable. Colorectal cancer is *generally* a slower-growing cancer. This means it would be extremely unlikely to have a clear colonoscopy and then find Stage 3 or 4 cancer at your next colonoscopy 2 years later, for example.
Often late-stage colorectal cancer is caused by late or too infrequent screening (i.e. someone gets cancer when they are 40 but don't find it until they are 50 because colonoscopy is not performed on the average person until age 50, and colorectal cancer often does not cause any symptoms until the late stages).
The best thing you can do to prevent cancer is make sure your inflammation is under control by finding medications that are effective for you and taking them faithfully, and getting screening colonoscopies beginning 8 years after diagnosis.