What is a colon polyp?
Polyps are benign growths involving the lining of the bowel (noncancerous tumors or neoplasms). They can occur in several locations in the gastrointestinal tract but are most common in the colon. They vary in size from less than a quarter of an inch to several inches in diameter. They look like small bumps growing from the lining of the bowel and protruding into the lumen (bowel cavity). They sometimes grow on a “stalk” and look like mushrooms. Many patients have several polyps scattered in different parts of the colon.

Are polyps dangerous?
There are two common types: hyperplastic polyp and adenoma. The hyperplastic polyp is not at risk for cancer and, therefore, is not as significant. The adenoma, however, is thought to be the precursor (origin) for almost all colon cancers, although most adenomas never become cancers. A biopsy (or small piece of removed tissue) is the only way to differentiate between hyperplastic and adenomatous polyps. Although it’s impossible to tell which adenomatous polyps will become cancers, larger polyps are more likely to become cancers and some of the largest ones (those larger than 1 inch) can already contain small areas of cancer. Because your doctor cannot be certain of the tissue type by the polyp’s appearance, doctors generally recommend removing all but the smallest polyps.

What are the symptoms?
Most polyps cause no symptoms. Larger ones can cause blood in the stools, but even they are usually asymptomatic. Therefore, the best way to detect polyps is by screening individuals with no symptoms.  Several screening techniques are available: testing stool specimens for traces of blood, performing sigmoidoscopy to look into the lower third of the colon, or using a radiology test such as a barium enema. If one of these tests finds or suspects polyps, your doctor will generally recommend colonoscopy (gold standard) to remove them. Because colonoscopy is the most accurate way to detect polyps, many experts now recommend colonoscopy as a screening method so that any polyps found or suspected can be removed during the same procedure.

But some people do have symptoms like these:

  • bleeding from the anus. You might notice blood on your underwear or on toilet paper after you've had a bowel movement.
  • constipation or diarrhea that lasts more than a week.
  • blood in the stool. Blood can make stool look black, or it can show up as red streaks in the stool.

If you have any of these symptoms, see a doctor to find out what the problem is.

Who should get tested for polyps?
Anyone can get polyps, but certain people are more likely than others. You may have a greater chance of getting polyps if:

  • you're over 50. The older you get, the more likely you are to develop polyps.
  • you've had polyps before.
  • someone in your family has had polyps.
  • someone in your family has had cancer of the large intestine.   

How can I prevent polyps?
Doctors don't know of any one sure way to prevent polyps. But you might be able to lower your risk of getting them if you:

  • eat more fruits and vegetables and less fatty food
  • don't smoke
  • avoid alcohol
  • exercise every day
  • lose weight if you're overweight
  • Eating more calcium and folate can also lower your risk of getting polyps. Some foods that are rich in calcium are milk, cheese, and broccoli. Some
  • foods that are rich in folate are chickpeas, kidney beans, and spinach.

Some doctors think that aspirin might help prevent polyps. Studies are under way.

How are polyps removed?
Most polyps found during colonoscopy can be completely removed during the procedure. Various removal techniques are available; most involve severing them with a wire loop and/or burning the polyp base with an electric current. This is called polyp resection. Because the bowel’s lining isn’t sensitive to cutting or burning, polyp resection doesn’t cause discomfort. Resected polyps are then examined under a microscope to determine the tissue type and to detect any cancer.

How often do I need a colonoscopy if I have polyps removed?
Your doctor will decide when your next colonoscopy is necessary. The timing depends on several factors, including the number and size of polyps removed, the polyps’ tissue type and the quality of the colon cleansing for your previous procedure. The quality of cleansing affects your doctor’s ability to see the surface of the colon.

Key Points:

  • A polyp is extra tissue that grows inside the body. Most polyps are not harmful.
  • Symptoms may include constipation or diarrhea for more than a week or blood on your underwear, on toilet paper, or in your stool.
  • Many polyps do not cause symptoms.
  • Doctors remove all polyps and test them for cancer.
  • Talk to your doctor about getting tested for polyps if:
    • you have any symptoms
    • you're 50 years old or older
    • someone in your family has had polyps or colon cancer