Colon polyps are growths in the colon or rectum. The cause of most colon polyps is not known.
Most polyps do not cause symptoms. But large polyps are more likely than small polyps to cause symptoms such as rectal bleeding.
Some polyps are attached to the wall of the colon or rectum by a stalk or stem (pedunculated). Some have a broad base with little or no stalk (sessile).