Please consult with your doctor but it is my understanding that a cancer diagnosis isn't really a serious danger if you are getting a colonoscopy every year.
Why Entyzio, it is a very expensive drug that can have serious side effects. I am sure your doctor is advising what he thinks is best for your health, but it wouldn't hurt to check out this website to see if he is receiving money from the makers of Entyzio.
https://projects.propublica.org/docdollars/