U.S. Department 


of Health and
 

Human Services 

What I need to know about
 

Colon Polyps Colon Polyps 

National Digestive Diseases 

NATIONAL INSTITUTES OF HEALTH Information Clearinghouse 

 

U.S. Department 


of Health and
 

Human Services
 

What I need to know about 

Colon Polyps 

National Digestive Diseases 

NATIONAL INSTITUTES OF HEALTH Information Clearinghouse 
Contents
 

What are colon polyps? .......................................... 1 


Are colon polyps cancerous?.................................. 2 


Who gets colon polyps? .......................................... 3 


What are the symptoms of colon polyps? ............. 4 


How does the doctor test for colon polyps? ......... 5
 

Who should get tested for colon polyps?.............. 7 


How are colon polyps treated? .............................. 8
 

How can I prevent colon polyps?........................... 9 


Points to Remember ............................................. 10 


Hope through Research ....................................... 11
 

Pronunciation Guide............................................. 12
 

For More Information .......................................... 13
 

Acknowledgments ................................................. 14
 
 

 

 

 

 

 

 

 

 

 

What are colon polyps? 

A colon polyp* is a growth on the surface of the 

colon, also called the large intestine. Sometimes, 

a person can have more than one colon polyp. 

Colon polyps can be raised or flat. 

The large intestine is the long, hollow tube at the 

end of your digestive tract. The large intestine 

absorbs water from stool 

and changes it from a 

liquid to a solid. Stool 

is the waste that passes 

through the rectum and 

anus as a bowel movement. 

Digestive tract with the 

large intestine highlighted. 

*See page 12 for tips on how to say the 

words in bold type. 

1 
 

 

 

 

Are colon polyps cancerous? 

Some colon polyps are benign, which means they 

are not cancer. But some types of polyps may 

already be cancer or can become cancer. Flat 

polyps can be smaller and harder to see and are 

more likely to be cancer than raised polyps. Polyps 

can usually be removed during colonoscopy—the 

test used to check for colon polyps. 

Normal 

intestinal 

fold Normal 

intestinal 

fold 

Polyp 

Colon polyp. 

2 
 

 

 

 

 

Who gets colon polyps? 

Anyone can get colon polyps, but certain people 

are more likely to get them than others. You may 

have a greater chance of getting polyps if 

l	 you’re 50 years of age or older 


l	 you’ve had polyps before
 

l	 someone in your family has had polyps 


l	 someone in your family has had cancer of 


the large intestine, also called colon cancer 

l	 you’ve had uterine or ovarian cancer before 

age 50 

You may also be more likely to get colon 

polyps if you 

l	 eat a lot of fatty foods 

l	 smoke 

l	 drink alcohol 

l	 don’t exercise 

l	 weigh too much 

3 

Find out if someone in your family 

has had polyps. 
 

 

 

 

 

 

 

 

What are the symptoms of 


colon polyps?
 

Most people with colon polyps do not have 


symptoms. Often, people don’t know they have 


one until the doctor finds it during a regular 


checkup or while testing for something else.
 

But some people do have symptoms, such as 

l	 bleeding from the anus. The anus is the opening 

at the end of the digestive tract where stool 

leaves the body. You might notice blood on your 

underwear or on toilet paper after you’ve had a 

bowel movement. 

l	 constipation or diarrhea that lasts more than 

a week. 

l	 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. 

4 
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

How does the doctor test for 


colon polyps?
 

The doctor can use one or more tests to check for 

colon polyps. 

l	 Barium enema. The doctor puts a liquid called 

barium into your rectum before taking x rays 

of your large intestine. Barium makes your 

intestine look white in the pictures. Polyps are 

dark, so they’re easy to see. 

l	 Sigmoidoscopy. With this test, the doctor puts 

a thin, flexible tube into your rectum. The tube 

is called a sigmoidoscope, and it has a light in it. 

The doctor uses the sigmoidoscope to look at the 

last third of your large intestine. 

l	 Colonoscopy. The doctor will give you medicine 

to sedate you during the colonoscopy. This test 

is like the sigmoidoscopy, but the doctor looks 

at the entire large intestine with a long, flexible 

tube with a camera that shows images on a TV 

screen. The tube has a tool that can remove 

polyps. The doctor usually removes polyps 

during colonoscopy. 

l	 Computerized tomography (CT) scan. With this 

test, also called virtual colonoscopy, the doctor 

puts a thin, flexible tube into your rectum. A 

machine using x rays and computers creates 

pictures of the large intestine that can be seen 

on a screen. 

5 
 

 

 

 

The CT scan takes less time than a colonoscopy 

because polyps are not removed during the test. 

If the CT scan shows polyps, you will need a 

colonoscopy so they can be removed. 

l	 Stool test. The doctor will ask you to bring a 

stool sample in a special cup. The stool is tested 

in the laboratory for signs of cancer, such as 

DNA changes or blood. 

Colonoscopy or sigmoidoscopy testing. 

6 
 

 

 

Who should get tested for 


colon polyps?
 

Talk with your doctor about getting tested for 

colon polyps if you’re 50 years of age or older, 

or earlier if you have symptoms or someone in 

your family has had polyps or colon cancer. 

7 
Polyp 

Intestinal 

folds 

Colonoscope 

 

 

 

 

How are colon polyps treated? 

In most cases, the doctor removes colon polyps 

during sigmoidoscopy or colonoscopy. The polyps 

are then tested for cancer. 

If you’ve had colon polyps, the doctor will want you 

to get tested regularly in the future. 

Polyp removal. 

8 
 

 

 

 

 

 

 

 

 

 

l don’t smoke 

l avoid alcohol 

l exercise most days of the week 

l lose weight if you’re overweight 

Eating more calcium may also lower your risk of 

getting polyps. Some foods that are rich in calcium 

are milk, cheese, yogurt, and broccoli. 

Taking a low dose of aspirin every day might help 

prevent polyps. Talk with your doctor before 

starting any medication. 

How can I prevent colon polyps? 

Doctors don’t know of one sure way to prevent 

colon polyps. But you might be able to lower your 

risk of getting them if you 

l eat more fruits and vegetables and less fatty food 

9 
 

 

 

 

 

 

 

 

 

 

Points to Remember 

l	 A colon polyp is a growth on the surface of the 

colon, also called the large intestine. 

l	 Colon polyps can be raised or flat. 

l	 Some colon polyps are benign, which means they 

are not cancer. 

l	 Some types of polyps may already be cancer or 

can become cancer. Flat polyps can be smaller 

and harder to see and are more likely to be 

cancer than raised polyps. 

l	 Most people with colon polyps do not have 

symptoms. 

l	 Symptoms may include constipation or 

diarrhea for more than a week or blood on your 

underwear, on toilet paper, or in your stool. 

l	 Doctors remove most colon polyps and test them 

for cancer. 

l	 Talk with your doctor about getting tested for 

colon polyps if you’re 50 years of age or older, or 

earlier if you have symptoms or someone in your 

family has had polyps or colon cancer. 

10
 
 

 

 

 

 

 

 

 

 

 

Hope through Research 

The National Institute of Diabetes and Digestive 

and Kidney Diseases’ Division of Digestive 

Diseases and Nutrition supports research into 

digestive conditions, including colon polyps. 

Researchers are studying why some people are 

more likely to get colon polyps than others. 

Researchers are also studying new tests and 

treatments to lower the risk of colon cancer in 

people with colon polyps. 

Participants in clinical trials can play a more 

active role in their own health care, gain access to 

new research treatments before they are widely 

available, and help others by contributing to 

medical research. For information about current 

studies, visit www.ClinicalTrials.gov. 

11 
 

Pronunciation Guide 

anus (AY-nuhss) 


barium enema (BA-ree-uhm) (EN-uh-muh)
 

benign (bee-NYN)
 

colonoscopy (KOH-lon-OSS-kuh-pee)
 

computerized tomography scan (kom-PYOO-tureyezd) (toh-MOG-ruh-fee) (skan)
 

DNA (DEE-EN-AY) 


intestine (in-TESS-tin) 


polyp (POL-ip) 


rectum (REK-tuhm) 


sigmoidoscopy (SIG-moy-DOSS-kuh-pee)
 

stool test (stool) (test)
 

virtual (VUR-chuh-wuhl)
 

12
 
For More Information 

American College of Gastroenterology 

P.O. Box 342260
 

Bethesda, MD 20827–2260
 

Phone: 301–263–9000
 

Internet: www.acg.gi.org
 

American Gastroenterological Association 

4930 Del Ray Avenue 

Bethesda, MD 20814 

Phone: 301–654–2055 

Fax: 301–654–5920 

Email: member@gastro.org 

Internet: www.gastro.org 

American Society for Gastrointestinal Endoscopy 

1520 Kensington Road, Suite 202 

Oak Brook, IL 60523 

Phone: 1–866–353–ASGE (2743) or 630–573–0600 

Fax: 630–573–0691 

Email: info@asge.org 

Internet: www.asge.org 

National Cancer Institute 

Cancer Information Service 

6116 Executive Boulevard, Room 3036A 

Bethesda, MD 20892–8322 

Phone: 1–800–4–CANCER (422–6237) 

or 301–496–6631 

Email: cancergovstaff@mail.nih.gov 

Internet: www.nci.nih.gov 

13 
 

 

 

Acknowledgments 

The National Digestive Diseases Information 

Clearinghouse (NDDIC) would like to thank the 

following individuals for assisting with the scientific 

and editorial review of the original version of this 

publication: 

C. Richard Boland, M.D.
 

University of California at San Diego
 

Francis M. Giardiello, M.D.
 

Johns Hopkins Hospital
 

The NDDIC would like to thank Michael B. Wallace, 

M.D., Mayo Clinic, Jacksonville, FL, for his review 

of the 2008 version. 

Thank you also to Anne Barker, R.N., B.S.N., at 

the Health Alliance, Columbia, MD, for facilitating 

field-testing of this publication. 

14
 
 

 

National Digestive Diseases 

Information Clearinghouse 

2 Information Way 

Bethesda, MD 20892–3570 

Phone: 1–800–891–5389 

TTY: 1–866–569–1162 

Fax: 703–738–4929 

Email: nddic@info.niddk.nih.gov 

Internet: www.digestive.niddk.nih.gov 

The National Digestive Diseases Information Clearinghouse 

(NDDIC) is a service of the National Institute of Diabetes and 

Digestive and Kidney Diseases (NIDDK). The NIDDK is part 

of the National Institutes of Health of the U.S. Department 

of Health and Human Services. Established in 1980, the 

Clearinghouse provides information about digestive diseases to 

people with digestive disorders and to their families, health care 

professionals, and the public. The NDDIC answers inquiries, 

develops and distributes publications, and works closely with 

professional and patient organizations and Government 

agencies to coordinate resources about digestive diseases. 

Publications produced by the Clearinghouse are carefully 

reviewed by both NIDDK scientists and outside experts. 

This publication is not copyrighted. The Clearinghouse encourages users 

of this booklet to duplicate and distribute as many copies as desired. 

This booklet is also available at www.digestive.niddk.nih.gov.

This publication may contain information about medications. When prepared, this 

publication included the most current information available. For updates or for 

questions about any medications, contact the U.S. Food and Drug Administration 

toll-free at 1–888–INFO–FDA (463–6332) or visit www.fda.gov. Consult your 

doctor for more information. 
U.S. DEPArTmENT OF HEALTH 

AND HUmAN SErvICES 

National Institutes of Health 

NIH Publication No. 09–4977 

November 2008