Overview

What is colon cancer?

Colon cancer happens when cells that are not normal grow in your colon. These cells often form in polyps, which are small growths in the colon. Not all colon polyps turn into cancer. But most colon cancer starts in a polyp.

Colon cancer occurs most often in people older than 50.

Who should be screened for it?

Your risk for colorectal cancer gets higher as you get older. If you are not at high risk, experts recommend regular screening for adults ages 50 to 74.^{footnote 1} Talk with your doctor about your risk and when to start and stop screening.

How often you need screening depends on the type of test you get:

Stool tests.

Every year for FIT.

Tests that look inside the colon.

Every 10 years for sigmoidoscopy.

Every 10 years for colonoscopy.

Experts agree that people at higher risk may need to be tested sooner and more often. This includes people who have a strong family history of colon cancer. Talk to your doctor about which test is best for you and when to be tested.