Colon polyps are growths on the lining of the colon or rectum. The colon and the rectum are parts of the large intestine, which is part of the digestive system.
There are two kinds of polyps: adenomatous and hyperplastic. Adenomatous polyps can become larger over time and may develop into cancer. Hyperplastic polyps do not increase in size and do not become cancerous.
The cause of colon polyps is unknown but it may be partly hereditary. Also, there is a genetic condition called polyposis coli that is characterized by the occurrence of thousands of adenomatous polyps throughout the bowel.
A risk factor is something that increases your chances of getting a disease or condition.
Risk factors for colon polyps include:
- Age: over 50 years
- Family members with colon polyps
- History of colorectal cancer (or cancer of the large intestine)
Often, no symptoms are present and the polyps are only found during an endoscopy or x-ray. If symptoms are present, they can include:
- Rectal bleeding
- Diarrhea, constipation, and/or bloating that lasts over a period of time
- Abdominal pain, rarely
The doctor will ask about your symptoms and medical history and perform a physical exam. Tests may include:
- Digital Rectal Exam – the doctor inserts a gloved finger into the rectum to feel for polyps.
- Stool Test – a sample of your stool is checked for blood.
- Sigmoidoscopy – a thin, lighted, flexible tube is inserted into the rectum to examine the rectal area and the lower colon.
- Barium Enema and X-Ray – a barium fluid is injected into the colon and rectum. Several x-rays are taken; the barium makes your colon show up on x-ray.
- Biopsy – a sample of tissue is removed for testing to determine whether the polyp is adenomatous or hyperplastic, and to check for the presence of cancer cells.
Depending on the size of the polyp, it may be removed. Large polyps are at high risk for becoming cancerous and should be removed. Usually, polyps can be removed by colonoscopy. Before a colonoscopy, you will be given laxatives to clean out your bowel and you may be sedated. Then a thin, lighted, flexible tube is passed through the rectum and into the colon. The polyps can be cut out through the tube using a wire.
If the polyps are very large, you may need to have surgery to have them removed. Your doctor may send the tissue from the removed polyps to be tested for cancerous or pre-cancerous cells.
It’s not clear how polyps can be prevented. However, the following guidelines can help you stay healthy and may help prevent not only polyps but also colon cancer:
- Eat a diet high in fiber with plenty of fruits, vegetables, and whole grains.
- Minimize the amount of animal fat in your diet. This occurs in beef and other meat products as well as full-fat dairy products.
- Exercise regularly.
- Maintain a healthy weight.
- Don't smoke.
- See your doctor for regular screenings after the age of 50.
- More frequent screenings may be warranted if polyps are found
There is some early evidence that non-steroidal antiinflammatory medications like aspirin and the Cox2 inhibitors (Celebrex, Vioxx, Bextra) may slow down the growth of polyps. Ask your doctor if these drugs are appropriate for you.
Please Note: On September 30, 2004, Merck & Co., Inc. announced a voluntary withdrawal of Vioxx(R) (rofecoxib) from the U.S. and worldwide market due to safety concerns. A recent study showed a small but significant increased risk of cardiovascular events (such as heart attack) in patients taking the prescription medication. Vioxx(R) is a so-called "selective" non-steroidal anti-inflammatory drug (NSAID) specially designed to lower the risk of stomach irritation. It is commonly used in the treatment of acute and chronic pain associated with arthritis, menstruation and other conditions. Since Merck's withdrawal of Vioxx(R), evidence has come to light regarding similar dangers posed by the other popular selective NSAID, Celebrex(R) (cefecoxib), which is produced by Pfizer. Many physicians now question the wisdom of prescribing any medications from the COX-2 class.