Educational Resource | Articles | Los Angeles Gastroenterology Group
Colon Polyp
Colon polyp is a benign growth that arises in the lining of the large intestine. Although it can occur in other part of gastrointestinal tract (GI tract), they occur most commonly 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.
How Common Are Colon Polyps?
Polyps are very common condition among adult population. In fact, older you are, the higher the risk of developing colon polyp. Although the exact cause of colon polyp is not entirely clear, they likely include genetic factors as well as dietary and environmental factors.
What Are Common Risks for Developing Polyps?
The most important risk for developing colonic polyp is age. Older you are, the higher the risk. A family history of colon polyps or colon cancer also increases the risk of colon polyp by up to 2 to 3 fold. In addition, patients with a past history of polyps or colon cancer are at an increased risk of developing newer additional polyps.
Are There Different Types of Polyps?
There are two common types of colon polyps: hyperplastic polyp and adenomatous polyp. The hyperplastic polyp is believed not to increase the risk of colon cancer and, therefore, is not cause for concern. The adenoma, however, is thought to be the precursor for most colon cancer. Although it is very difficult to tell the exact type of polyp during an examination, if a biopsy (or small sampling of tissue) is performed, the exact tissue type: hyperplastic and adenomatous polyp can be assessed. In general, when polyps are found during colonoscopy, most polyps that are detected, therefore, are removed during the procedure. The technique used to removed colon polyp is called polypectomy
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How Are Polyps Found?
Most individuals with colon polyp are not aware that they have colon polyp since they usually do not cause any symptoms. When polyps become large enough, it can bleed or at times cause diarrhea. Since there are limited symptoms associated with colon polyp, the best way to detect this pre-cancerous lesion, colon polyp, is to undergo screening colonoscopy. Although there are other screening methods available including testing stool specimens for traces of blood, performing sigmoidoscopy to look into the lower, distal third of the colon, or using a radiology test such as a barium enema, colonoscopy is preferred by most doctors and patients. There is a newer screening test called CT colonography which evaluates the inside of colon using CT scan. Although it is convenient and does not require sedation, it is in fact associated with an increased radiation exposure which in itself may cause cancer. If we are found to have colonic polyps, it is generally recommend that you still undergo colonoscopy to remove them. Because colonoscopy is the most accurate way to detect polyps, most individuals choose colonoscopy when undergoing screening both to detect and remove any polyp if found during the same procedure.
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 polypectomy. The technique is not associated with any pain or discomfort. After the polyp is removed, it is later examined under a microscope to determine the tissue type (e.g. hyperplastic or adenoma) and to detect any cancer.
What Are the Risks of Polyp Removal?
Polyp removal during colonoscopy is a common, outpatient procedure. Although rare, possible complications, include bleeding from the polypectomy site and perforation (a hole) of the colon. Bleeding from the polypectomy site can be immediate or delayed for several days; persistent bleeding can almost always be stopped by treatment during colonoscopy. Perforations usually require surgery to repair.
How Often Do I Need Colonoscopy if I Have Polyps Removed?
There are various factors that goes into consideration in the decision on how to follow-up after polypectomy. 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.
If the polyps were small and the entire colon was well seen during your colonoscopy, it is generally recommend a repeat colonoscopy in 3-5 years. If your repeat colonoscopy doesn’t show any indication of polyps, you might not need another procedure for an additional 5-10 years.
However, if the polyps were large and flat, it may be necessary to repeat the examination after several months or a year to ensure that all polyps are completely removed.
