Topic Overview
What are colon polyps?
Colon polyps are growths in your
large intestine (colon). The cause of most colon polyps is not known, but they
are common in adults.
Most colon polyps are not cancer. But some
growths can turn into
colon cancer. If a colon polyp is the kind that can
turn into cancer, it usually takes many years for that to happen.
People over 50 are more likely than younger people to get colon cancer.
Experts recommend routine colon cancer testing for everyone age 50 and older
who has a normal risk for colon cancer. People with a higher risk, such as
African Americans and people with a strong family history of colon cancer,
may need to be tested sooner. Talk to your doctor about when you should be tested.
Finding and removing colon polyps can prevent colon cancer.
What are the symptoms?
You can have colon polyps
and not know it because they usually don't cause symptoms. They are usually
found during routine screening tests for colon cancer. A screening test looks
for signs of a disease when there are no symptoms.
If polyps get
large, they can cause symptoms. You may have bleeding from your rectum or a
change in your bowel habits. A change in bowel habits includes diarrhea,
constipation, going to the bathroom more often or less often than usual, or a
change in the way your stool looks.
How are colon polyps diagnosed?
Most polyps are
found during tests for colon cancer. Experts recommend routine colon cancer
testing for everyone age 50 and older who has a normal risk for colon cancer.
People with a higher risk, such as African Americans and people with a strong
family history of colon cancer, may need to be tested sooner. The tests for colon
cancer are:
- Stool tests. In a fecal occult blood test
(FOBT), a fecal immunochemical test (FIT), and a stool DNA test (sDNA), stool
samples are checked for signs of cancer.
- Colonoscopy. In this test, the doctor inserts a small
viewing tube all the way into your colon and looks for polyps. The doctor can
also take out any polyps he or she finds.
- Flexible sigmoidoscopy. This test is like a
colonoscopy, except that the viewing tube is shorter so the doctor can only
look at the last part of your colon. Doctors can remove polyps during this
test.
- Computed tomographic colonography (CTC). This test is also
called a virtual colonoscopy. A computer and X-rays make a detailed picture of
the colon to help the doctor look for polyps.
Doctors often recommend colonoscopy because it lets them
look at the whole colon and remove any polyps they find. If polyps are found
during another type of test, you may still need colonoscopy so the doctor can
remove the polyps.
What increases my risk of getting colon polyps?
You are more likely to have colon polyps if:
- You are over 50.
- Colon polyps or colon cancer runs
in your family.
- You inherited a certain gene that causes you to
develop polyps. People with this gene are much more likely than others to get
the kind of polyps that turn into colon cancer.
How are they treated?
Doctors usually remove colon
polyps because some of them can turn into colon cancer. Most polyps are removed
during a colonoscopy. You may need to have surgery if you have a large
polyp.
Once you have had polyps, you have a higher chance of developing new polyps. If you have had polyps removed,
it is important to have follow-up testing to look for more polyps. Talk to your
doctor about how often you need to be tested.
Frequently Asked Questions
Learning about colon polyps: | |
Being diagnosed: | |
Getting treatment: | |
Symptoms
Colon polyps usually do not cause
symptoms unless they are larger than
1 cm (0.4 in.) or they are
cancerous. The most common symptom is rectal bleeding. Sometimes the bleeding
may not be obvious (occult) and may only be discovered after doing a screening
test for blood in the stool called a
fecal occult blood test (FOBT).
Colon
polyps usually do not cause pain or a change in bowel habits unless they are
large and are blocking part of the colon. These symptoms are rare because
polyps usually are discovered and removed before they become large enough to
cause problems.
After cancer develops, additional symptoms may
occur, such as changes in bowel habits and significant weight loss.
Exams and Tests
Unless
colon polyps are large and cause bleeding or pain, the
only way to know if you have polyps is to have one or more tests that explore
the inside surface of your colon.
Several tests can be used to
detect colon polyps. Two of these exams,
flexible sigmoidoscopy and
colonoscopy, also can be used to collect tissue
samples (called a
biopsy) or to remove colon polyps. All the tests may
be used to screen for colon polyps and colon cancer and as follow-up tests
after colon polyps have been removed. There are two basic types of tests—stool
tests and tests that look inside your body.
Stool tests
- Fecal occult blood test (FOBT). A
fecal occult blood test (FOBT) is done to look for
microscopic amounts of blood in stool. FOBT is a simple, low-cost screening
tool for colon polyps or colon cancer. FOBT has been shown in studies to reduce
the number of deaths from colon cancer. By itself, an FOBT is not evidence of
colon polyps or colon cancer. And a negative FOBT (no blood found) does not
mean that you do not have
polyps or colorectal cancer. If a fecal occult blood test is
positive for blood in the stool, it is important to have a colonoscopy to help
your doctor find the source of the blood and remove polyps if they are
found.
- Fecal immunochemical test (FIT). This
test also looks for blood in the stool, but it is more specific than the FOBT.
There aren't as many restrictions on what you can eat before having this test,
and fewer stool samples are required. If the test is positive for blood in the
stool, you may need to have a colonoscopy.
- Stool DNA test (sDNA). This test checks for changes to the cells in the colon
by looking at DNA in the stool. Certain kinds of changes in cell DNA
happen when you have cancer. Like the other stool tests, if your test is
positive, you may need to have a colonoscopy.
Tests that look inside your body
- Flexible sigmoidoscopy.Flexible sigmoidoscopy allows the doctor to look at
the lower third of the colon. During a sigmoidoscopy exam, samples of any
growths can be collected (biopsied). And precancerous and cancerous polyps can
sometimes be removed.
- Colonoscopy. This
screening method lets a doctor inspect the entire colon for polyps and cancer.
During a
colonoscopy, samples of any growths can be collected
(biopsied). And precancerous and cancerous polyps usually can be
removed.
- Computed tomographic colonography (CTC).
This test is also called
virtual colonoscopy. A computer and X-rays make a
detailed picture of the colon to help the doctor look for polyps. If this test
finds polyps, you may need to have a colonoscopy.
Screening for colon cancer
Screening for colon
cancer with a single test or a combination of tests reduces your chance of
having complications and dying from colon cancer.
Experts recommend routine colon cancer testing for
everyone age 50 and older who has a normal risk for colon cancer. People with a
higher risk, such as African Americans and people with a strong family history
of colon cancer, may need to be tested sooner. Talk to your doctor about when you
should be tested.
If you are older than 50, screening may lower
your risk of dying from colon cancer. Screening options include the following
tests.
- Stool tests, such as:
- A fecal occult blood test (FOBT) every year.
- A
fecal immunochemical test (FIT) every year.
- A stool DNA test
(sDNA) every 5 years.
- Flexible sigmoidoscopy every 5
years.
- Stool test (FOBT or FIT) every year and a flexible
sigmoidoscopy every 5 years.
- Colonoscopy every 10 years.
- Computed tomographic
colonography (CTC), known as virtual colonoscopy, every 5 years.
The method of screening that you have depends on your
personal preferences, your doctor's preferences, and what the clinic or office
you go to is able to do.
People with a
higher risk for colon cancer, such as African
Americans and people with a strong family history of colon cancer, may need to be tested sooner. Talk to your doctor about when you should be tested.
If you have a family history of
familial adenomatous polyposis (FAP), you should start screening tests at age 10 or 12.
If you have a family
history of
hereditary nonpolyposis colon cancer (HNPCC), you
should have a colonoscopy every 1 to 2 years starting at age 20 to 25, or 10
years younger than the age at which the youngest family member who has
colorectal cancer was diagnosed, whichever comes first.
The
decisions about when to start and stop screening for colon cancer should be
made with your doctor. These decisions will depend on how old you are, your
family history, any health problems you may have, and the benefits you can
expect from regular screening.
Follow-up testing
If a
biopsy of polyps obtained during screening reveals
only
hyperplastic polyps of any size, routine follow-up
screening is all that is needed. These polyps do not become cancerous.
Most doctors agree that if you have had one or more
adenomatous polyps removed, you probably need regular
follow-up colonoscopy exams every few years. This type of polyp is more likely
to turn into cancer, but that risk is still very low. How often you need a
colonoscopy may depend on the number and size of the polyps, your age, your
health, and other risk factors that you may have for polyps. Talk with your
doctor about the follow-up testing schedule that is right for you.
Treatment Overview
Most
colon polyps do not cause any problems, but a sample
of polyp tissue (called a
biopsy) can be removed during screening if you have a
flexible sigmoidoscopy or
colonoscopy. The tissue is examined to find out if it
is the kind of tissue that could become cancer.
Initial treatment
If
adenomatous polyps are found during an exam with
flexible sigmoidoscopy, a colonoscopy will be done to look for and remove any
polyps in the rest of the colon.
The bigger a
colon polyp is, especially if it is larger than
1 cm (0.4 in.), the more likely
it is that the polyp will be adenomatous or contain cancer cells and need to be
removed.
In some cases, very small polyps [5 mm (0.2 in.) or less] may not be removed.
Some studies have concluded that even if they contain adenomatous tissue, these
polyps take so many years to grow that they pose little risk of cancer, except
in people who have inherited (familial) polyp syndromes.1
Most colon polyps are not likely to develop
into cancer. If only
hyperplastic polyps are found during your flexible
sigmoidoscopy, you likely do not need to have a colonoscopy. These polyps do
not become cancerous. In this case you can continue your regular screenings,
unless you are at an
increased risk for colon cancer because of a family
history of colon cancer or an inherited polyp syndrome.
Risks of removing polyps during colonoscopy
Complications from colonoscopy are rare. There is a slight risk
of:
- Puncturing the colon (less than 1 in 1,000)
or causing severe bleeding by damaging the wall of the colon (less than 3 in
1,000).
- Bleeding caused by removing a
polyp.
- Complications from sedatives given during the
procedure.
Ongoing treatment
Regular screenings for
colon polyps are the best way to prevent polyps from
developing into colon cancer.
Most colon polyps can be identified and removed during a
colonoscopy.
If you have had one or more adenomatous polyps
removed, you probably need regular follow-up colonoscopy exams every 3 to 5
years. Talk with your doctor about the follow-up schedule that he or she thinks
is best for you.
Treatment if the condition gets worse
Surgery is
sometimes needed for large
colon polyps that have a broad area of attachment
(sessile polyps) to the colon wall. These large polyps sometimes cannot be
removed safely during a colonoscopy and may be more likely to develop into
cancer.
If cancer is found when the colon polyps are examined, you
will begin treatment for
colorectal cancer. For more information, see the topic
Colorectal Cancer.
Home Treatment
No home treatment is done for
colon polyps. See the Treatment Overview section of
this topic for more information.
But you can take action that may
prevent colon polyps from developing:
- Maintain a healthy body weight.
- Quit
smoking.
- Use alcohol in moderation. Moderate alcohol use usually is
defined as 1
alcoholic beverage a day for women and 2 for
men.
Experts are not yet certain that these approaches prevent
colon polyps or
colorectal cancer.
These self-care
methods should not be a substitute for regular colorectal screening, especially
if you are older than 50 or are at
increased risk for colon polyps or colon cancer. While
these approaches may decrease your risk for colon polyps, they will not prevent
you from ever having colon polyps.
Other Places To Get Help
Organizations
| American Cancer Society (ACS) |
| Phone: | 1-800-ACS-2345 (1-800-227-2345) |
| TDD: | 1-866-228-4327 toll-free |
| Web Address: | www.cancer.org |
| |
The American Cancer Society (ACS) conducts educational
programs and offers many services to people with cancer and to their families.
Staff at the toll-free numbers have information about services and activities
in local areas and can provide referrals to local ACS divisions. |
|
| American College of
Gastroenterology |
| Phone: | (301) 263-9000 |
| Web Address: | http://patients.gi.org |
| |
The American College of Gastroenterology is an
organization of digestive disease specialists. The website contains
information about common gastrointestinal problems. |
|
| American Society of Colon and Rectal
Surgeons |
| 85 West Algonquin Road |
| Suite 550 |
| Arlington Heights, IL 60005 |
| Phone: | (847) 290-9184 |
| Fax: | (847) 290-9203 |
| Email: | ascrs@fascrs.org |
| Web Address: | www.fascrs.org |
| |
The American Society of Colon and Rectal Surgeons is the leading
professional society representing more than 1,000 board-certified colon and
rectal surgeons and other surgeons dedicated to treating people with diseases
and disorders affecting the colon, rectum, and anus. |
|
| National Digestive Diseases Information Clearinghouse |
| 2 Information Way |
| Bethesda, MD 20892-3570 |
| Phone: | 1-800-891-5389 |
| Fax: | (703) 738-4929 |
| TDD: | 1-866-569-1162
toll-free |
| Email: | nddic@info.niddk.nih.gov |
| Web Address: | www.digestive.niddk.nih.gov |
| |
This clearinghouse is a service of the U.S. National
Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), part of the
U.S. National Institutes of Health. The clearinghouse answers questions;
develops, reviews, and sends out publications; and coordinates information
resources about digestive diseases. Publications produced by the clearinghouse
are reviewed carefully for scientific accuracy, content, and readability.
|
|
References
Citations
- Itzkowitz SH, Potack J (2010). Colonic polyps and polyposis syndromes. In M Feldman et al., eds., Sleisenger and Fordtran's Gastrointestinal and Liver Disease, 9th ed., vol. 2, pp. 2155—2189. Philadelphia: Saunders.
Other Works Consulted
- Bresalier RS (2010). Colorectal cancer. In M Feldman et al., eds. Sleisenger and Fordtran’s Gastrointestinal and Liver Disease, 9th ed., vol. 2, pp. 2191–2238. Philadelphia: Saunders.
- Iqbal CW, et al. (2008). Surgical management and
outcomes of 165 colonoscopic perforations from a single institution.
Archives of Surgery, 143(7): 701–707.
- Kastrinos F, Syngal S (2009). Colorectal cancer screening. In NJ Greenberger et al., eds., Current Diagnosis and Treatment: Gastroenterology, Hepatology, and Endoscopy, pp. 256–268. New York: McGraw-Hill.
- Lanza E, et al. (2007). The Polyp Prevention Trial—Continued follow-up study: No effect of a low-fat, high-fiber, high-fruit, and -vegetable diet on adenoma recurrence eight years after randomization. Cancer Epidemiology, Biomarkers, and Prevention, 16(9): 1745–1752.
- Levin B, et al. (2008). Screening and surveillance for
the early detection of colorectal cancer and adenomatous polyps, 2008: A joint
guideline from the American Cancer Society, the U.S. Multi-Society Task Force
on Colorectal Cancer, and the American College of Radiology. CA: A Cancer Journal for Clinicians, 58(3):
130–160.
- Rex DK, et al. (2009). American College of
Gastroenterology guidelines for colorectal cancer screening 2008.
American Journal of Gastroenterology, 104(3):
739–750.
Credits
| By | Healthwise Staff |
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| Primary Medical Reviewer | E. Gregory Thompson, MD - Internal Medicine |
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| Specialist Medical Reviewer | Jerome B. Simon, MD, FRCPC, FACP - Gastroenterology |
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| Last Revised | April 27, 2011 |
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