A colorectal polyp is a growth on the lining of the colon or rectum.
Intestinal polyps; Polyps - colorectal; Adenomatous polyps; Hyperplastic polyps; Villous adenomas
Polyps of the colon and rectum are usually benign. This means they are not cancerous and do not spread. You may have one or many polyps. They become more common with age.
Common polyp types include:
- Adenomatous polyps - which may develop into colon cancer over time.
- Hyperplastic polyp - which usually do not develop into colon cancer.
Polyps bigger than 1 centimeter have a higher cancer risk than polyps under 1 centimeter. Risk factors include:
- Family history of colon cancer or polyps
- A type of polyp called villous adenoma
Polyps may also be linked to some inherited disorders, including:
- Familial adenomatous polyposis
- Gardner syndrome
- Juvenile polyposis
- Lynch syndrome (HNPCC)
- Peutz-Jeghers syndrome
Polyps usually do not have symptoms. When present, symptoms may include:
- Blood in the stools
- Diarrhea (rare)
- Fatigue caused by losing blood over time
Exams and Tests
The health care provider will perform a physical exam. A large polyp may be felt during a rectal exam.
Most polyps are found with the following tests:
Colorectal polyps should be removed because some can develop into cancer. In most cases, the polyps may be removed during a colonoscopy.
For people with adenomatous polyps, new polyps can appear in the future. Follow-up colonoscopy is usually recommended 1 to 10 years later, depending on the:
- Person's age and general health
- Number of polyps
- Size and nature of the polyps
In rare cases, when polyps are very likely to turn into cancer, the doctor will recommend a colectomy. This is surgery to remove part of the colon that has the polyps.
Outlook is excellent if the polyps are removed. Polyps that are not removed can develop into cancer over time.
When to Contact a Medical Professional
Call your health care provider if you have:
- Blood in a bowel movement
- Change in bowel habits
To reduce your risk of developing polyps:
- Eat foods low in fat and eat more fruits, vegetables, and fiber.
- Do not smoke or drink alcohol in excess.
- Maintain a normal body weight.
- Get regular exercise.
Colonoscopy prevents colon cancer by removing polyps before they become cancer. People age 50 or older should consider having a colonoscopy or other screening test. This may reduce the chance of developing colon cancer, or at least help catch it in its most treatable stage. Those with a family history of colon cancer or colon polyps may need to be screened at an earlier age.
Taking aspirin or similar medicines may help reduce the risk of new polyps. Be aware that these medicines can have serious side effects if taken for a long time. Side effects include bleeding in the stomach or colon and heart disease. Talk with your doctor before taking these medicines.
Itzkowitz SH, Potack J. Colonic polyps and polyposis syndromes. In: Feldman M, Friedman LS, Brandt LJ, eds. Sleisenger and Fordtran's Gastrointestinal and Liver Disease Pathophysiology/Diagnosis/Management. 9th ed. Philadelphia, Pa: Elsevier Saunders; 2010:chap 122.
National Comprehensive Cancer Network. NCCN Clinical Practice Guidelines in Oncology (NCCN Guidelines): Colorectal cancer screening. Version 2.2013. Available at http://www.nccn.org/professionals/physician_gls/pdf/colorectal_screening.pdf Accessed October 24, 2013.
Reviewed By: George F. Longstreth, MD, Department of Gastroenterology, Kaiser Permanente Medical Care Program, San Diego, California. Also reviewed by David Zieve, MD, MHA, Bethanne Black, and the A.D.A.M. Editorial team.