Adenomatous polyps are a type of abnormal growth in the colon. While most colon polyps do not cause any problems, adenomatous polyps are thought to be the source of most colorectal cancer.

Adenomatous polyps usually grow very slowly, and it may be years before they turn into cancer, if they ever do. They usually are discovered during a routine sigmoidoscopy or colonoscopy and are removed. The discovery of adenomatous polyps in your colon means that you need to be screened for colorectal cancer more often than the average person.