This information was developed by the Publications Committee of the American Society for Gastrointestinal Endoscopy (ASGE). For more information about ASGE, visit www.asge.org.

Understanding Colon Polyps and Their Treatment

What is a colon polyp?

Polyps are benign growths (noncancer- Many experts ous tumors or neoplasms) involving recommend the lining of the bowel. They can occur POLYP colonoscopy as a in several locations in the gastrointes- screening method for colon cancer. tinal tract but are most common in the Colonoscopy may colon. They vary in size from less than detect polyps. a quarter of an inch to several inches in One advantage diameter. They look like small bumps of colonoscopy growing from the lining of the bowel over other screen- ing techniques is and protruding into the lumen (bow- that any polyps el cavity). They sometimes grow on a found or suspected “stalk” and look like mushrooms. Some can be removed polyps can also be flat. Many patients during the same have several polyps scattered in differ- procedure as the screening. ent parts of the colon. Some polyps can contain small areas of cancer, although the vast majority of polyps do not. formation. There may be a genetic risk run in families and increase the risk of How common are colon to develop polyps as well. polyps occurring at younger ages. polyps? What causes them? Polyps are very common in adults, who What are known risks for Are there different types of have an increased chance of acquiring developing polyps? polyps? them, especially as we get older. While The biggest risk factor for developing There are two common types: hyper- quite rare in 20-year-olds, it’s estimated polyps is being older than 50. A family plastic polyp and adenoma. The hy- that the average 60-year-old without history of colon polyps or colon cancer perplastic polyp is typically not at risk special risk factors for polyps has a 25 increases the risk of polyps. Also, pa- for cancer. The adenoma, however, is percent chance of having a polyp. We tients with a personal history of polyps thought to be the precursor (origin) don’t know what causes polyps. Some or colon cancer are at risk of developing for almost all colon cancers, although experts believe a high-fat, low-fiber new polyps. In addition, there are some most adenomas never become cancers. diet can be a predisposition to polyp rare polyp or cancer syndromes that Histology (examination of tissue under a microscope) is the best way to differ- Colonoscopy, the most accurate way to detect polyps among entiate between hyperplastic and ade- the available techniques, is almost always done on an nomatous polyps. Although it’s impos- outpatient basis and typically takes less than 45 minutes. sible 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 usually be certain of the tissue type by the polyp’s appearance, doc- tors generally recommend removing all polyps found during a colonoscopy.

1 f.y.i. TRANSVERSE COLON Most polyps cause no symptoms. Therefore, the best way to detect polyps is by screening individuals with no symptoms.

SIGMOID How are polyps found? ASCENDING COLON COLON Most polyps cause no symptoms. Larg- er ones can cause blood in the stool, DESCENDING but even they are usually asymptom- COLON atic. Therefore, the best way to detect CECUM polyps is by screening individuals with no symptoms. Several other screening techniques are available: testing stool specimens for traces of blood, perform- RECTUM ing sigmoidoscopy to look into the lower third of the colon or using a ra- diology test such as a barium enema or ANUS CT colonography. If one of these tests APPENDIX finds or suspects polyps, your doctor will generally recommend colonoscopy In a colonoscopy, the physician passes the endoscope to remove them. Because colonoscopy is through your rectum and into the colon to examine the the most accurate way to detect polyps, tissue of the colon wall for abnormalities such as polyps. many experts now recommend colonos- copy as a screening method so that any techniques are available; most involve How often do I need colonos- polyps found or suspected can be re- removing them with a wire loop, bi- copy if I have polyps removed? moved during the same procedure. opsy forceps and/or burning the Your doctor will decide when your next polyp base with an electric current. How are polyps removed? colonoscopy is necessary. The timing This is called polyp resection. Because depends on several factors, includ- Most polyps found during colonos- the bowel’s lining isn’t sensitive to ing the number and size of polyps copy can be completely removed dur- cutting or burning, polyp resection removed, the polyps’ tissue type and ing the procedure. Various removal doesn’t cause discomfort. Resected the quality of the colon cleansing for polyps are then examined under a your previous procedure. The quality microscope by a pathologist to deter- of cleansing affects your doctor’s ability mine the tissue type and to detect any to see the surface of the colon. If the cancer. If a large or unusual looking polyps were small and the entire colon polyp is removed or left for possible was well seen during your colonoscopy, surgical management, the endosco- doctors generally recommend a repeat pist may mark the site by injecting colonoscopy in three to five years. If small amounts of sterile India ink or your repeat colonoscopy doesn’t show carbon black into the bowel wall. This any indication of polyps, you might not is called endoscopic tattooing. need another procedure for an addi- tional five years. However, if the polyps What are the risks of polyp were large and flat, your doctor might removal? recommend an interval of only months Polyp removal (or polypectomy) during before a repeat colonoscopy to assure colonoscopy is a routine outpatient pro- complete polyp removal. Your doctor cedure. Possible complications, which will discuss those options with you. An endoscope is a medical device are uncommon, include bleeding from used by expert physicians to look inside the digestive tract the polypectomy site and perforation (a for abnormalities such as polyps. hole or tear) of the colon. Bleeding from The expert physician controls the the polypectomy site can be immediate movement of the flexible tube or delayed for several days; persistent using the endoscope handle. asge.org bleeding can almost always be stopped screen4coloncancer.org by treatment during another colonos- copy. Perforations rarely occur and may require surgery to repair. 2 Notes or questions:

This information is intended only to provide general guidance. It does not provide definitive medical advice. It is important that you consult your doc- tor about your specific condition.

Since its founding in 1941, the American Society for Gastrointestinal Endoscopy (ASGE) has been dedicated to advancing patient care and diges- tive health by promoting excellence in gastrointestinal endoscopy. ASGE, with more than 11,000 members worldwide, promotes the highest standards for endoscopic training and practice, fosters endoscopic research, and is the foremost resource for en- doscopic education. This information is the opinion of and provided by the American Society for Gastrointestinal Endoscopy.

Copyright © 2010. American Society for Gastrointestinal Endoscopy. All rights reserved. This information may not be reproduced without express written permission by ASGE. For permission requests, please contact the ASGE Communications Department at 630-673-0600.

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