A colon polyp is a small clump of cells that forms on the lining of the colon. Although most colon polyps are harmless, some become cancerous over time.
Anyone can develop colon polyps. But you're at higher risk if you're 50 or older, are overweight or a smoker, eat a high-fat, low-fiber diet, or have a personal or family history of colon polyps or colon cancer.
Usually colon polyps don't cause symptoms. That's why experts recommend regular screening. Colon polyps that are found in the early stages usually can be removed safely and completely. Screening helps prevent colon cancer, a common disease that's often fatal when it's found in its later stages.
Colon polyps often cause no symptoms. You might not even know you have a polyp until your doctor finds it during an examination of your bowel. Sometimes, however, you may have signs and symptoms such as:
When to see a doctor
You should be screened regularly for polyps if:
The last part of your digestive tract is a long muscular tube called the large intestine. The colon makes up most of the large intestine. The rectum and anus make up the end of the large intestine. The colon's main function is to absorb water, salt and other minerals from colon contents. Your rectum stores waste until it's eliminated from your body as stool.
Why polyps form
Polyps can develop anywhere in your large intestine. They can be small or large and flat (sessile) or mushroom shaped and attached to a stalk (pedunculated). In general, the larger a polyp, the greater the likelihood of cancer.
There are three main types of colon polyps:
Small colon polyps
This image of the inside of the colon shows two small polyps whose diameters are about the size of a pencil eraser (about 6 to 7 millimeters). ...
Large colon polyp
This image of the inside of the colon shows a large polyp. Large polyps are 10 millimeters (mm) or larger in diameter (25 mm equals about 1 inch). ...
This image of the inside of the colon shows colon cancer. ...
A number of factors may contribute to the formation of colon polyps and colon cancer. They include:
Inherited gene mutations
Some colon polyps may become cancerous (malignant). The earlier polyps are removed, the less likely it is that they will become malignant.
Preparing for your appointment
If it's suspected that you have colon polyps, you're likely to start by seeing your family doctor or a general practitioner. However, in some cases when you call to set up an appointment, you may be referred immediately to a gastroenterologist.
Because appointments can be brief, and there's often a lot of ground to cover, it's a good idea to be well prepared. Here's some information to help you get ready, and what to expect from your doctor.
What you can do
Your time with your doctor is limited, so preparing a list of questions ahead of time will help you make the most of your time together. List your questions from most important to least important in case time runs out. For colon polyps, some basic questions to ask your doctor include:
In addition to the questions that you've prepared to ask your doctor, don't hesitate to ask additional questions that may come up during your appointment.
What to expect from your doctor
Tests and diagnosis
Nearly all colon cancers develop from polyps, but the polyps grow slowly, usually over a period of years. Screening tests play a key role in detecting polyps before they become cancerous. These tests can also help find colorectal cancer in its early stages, when you have a good chance of recovery.
Several screening methods exist — each with its own benefits and risks. Be sure to discuss these with your doctor:
Treatments and drugs
Although some types of colon polyps are far more likely to become malignant than are others, a pathologist usually must examine polyp tissue under a microscope to determine whether it's potentially cancerous. For that reason, your doctor is likely to remove all polyps discovered during a bowel examination.
Endoscopic mucosal resection
Colon and rectum removal
You can greatly reduce your risk of colon polyps and colorectal cancer by having regular screenings and by making certain changes in your diet and lifestyle. The following suggestions may help lower your risk of colon polyps and colon cancer:
Last Updated: 2011-07-16
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