Also called bowel polyps or colorectal polyps, these are growths that project out from the lining of the colon or rectum. In most cases, the cause is unknown.
Polyps usually produce no symptoms and are discovered only during medical investigations for other reasons, such as during screening for colon cancer. If symptoms do occur, they may include diarrhea or constipation, blood in the feces, or bleeding from the rectum.
Polyps themselves are not cancerous, but some may develop into cancer, so if they are discovered, they need to be removed, usually by minimally invasive surgery.
Rarely, it may be necessary to remove part of the colon. Multiple polyps may occasionally be due to a rare inherited condition called familial adenomatous polyposis, in which hundreds of polyps grow in the lining of the colon and there is a high risk of colon cancer. For this reason, people with familial adenomatous polyposis may be advised to have the colon completely removed.