Colon polyps are growths in the colon or rectum. The cause of most colon polyps is not known.

A certain type of polyp called an adenomatous polyp is more likely than other types to develop into cancer over time.

Most polyps do not cause symptoms. But large polyps are more likely than small polyps to cause symptoms such as rectal bleeding or a change in bowel habits.

Colon polyps are diagnosed through screening tests. These tests include stool tests, such as the fecal occult blood test (FOBT), the fecal immunochemical test (FIT), and the stool DNA test (sDNA). They also include tests that look inside the body, such as flexible sigmoidoscopy, colonoscopy, and computed tomographic colonography (also called a virtual colonoscopy). Polyps can be removed or samples of tissue (biopsies) can be taken during flexible sigmoidoscopy and colonoscopy. Early diagnosis of adenomatous polyps may help prevent cancer or identify cancer at a stage when it might be more successfully treated.