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What is colorectal cancer?
Colorectal cancer is a term used to refer to cancer that
develops in the colon or the rectum. These cancers are sometimes
referred to separately as colon cancer or rectal cancer, depending on
where they start. Colon cancer and rectal cancer have many features in
common, which is why they are discussed together in this document.
The normal digestive system
The colon and rectum are parts of the digestive system, which
is also called the gastrointestinal (GI) system. The first part of the
digestive system processes food for energy, while the last part (the
colon and rectum) absorbs fluid to form solid waste (fecal matter or
stool) that then leaves the body.
In order to understand colorectal cancer, it helps to have
some basic knowledge about the normal structure and function of the
digestive system (see picture below).
After food is chewed and swallowed, it travels through the
esophagus to the stomach. There it is partly broken down and then sent
to the small intestine, also known as the small bowel. The word "small"
describes the diameter of the small intestine, which is narrower than
that of the large bowel (colon and rectum). Actually the small
intestine is the longest segment of the digestive system -- about 20
feet. The small intestine continues breaking down the food and absorbs
most of the nutrients.
The small bowel joins the colon in the right lower abdomen.
The colon (also called the large bowel or large intestine) is a
muscular tube about 5 feet long. The colon absorbs water and salt from
the food matter and serves as a storage place for waste matter.
The colon has 4 sections:
- The first section is called the ascending colon. It
starts with a small pouch (the cecum) where the small bowel attaches to
the colon and extends upward on the right side of the abdomen. The
cecum is also where the appendix attaches to the colon.
- The second section is called the transverse colon
since it goes across the body from the right to the left side in the
upper abdomen.
- The third section, the descending
colon, continues downward on the left side.
- The fourth and last section is known as the sigmoid colon
because of its "S" or "sigmoid" shape.
The waste matter that is left after going through the colon is
known as feces or stool. It goes into the rectum, the final 6 inches of
the digestive system, where it is stored until it passes out of the
body through the anus.

The wall of the colon and rectum is made up of several layers
of tissue. Colorectal cancer starts in the innermost layer and can grow
through some or all of the other layers. The stage (extent of spread)
of a colorectal cancer depends to a great degree on how deeply it
invades these layers and helps determine treatment options and
prognosis (outlook).
Abnormal growths in the colon or rectum
In most people, colorectal cancers develop slowly over several
years. Before a cancer develops, a growth of tissue or tumor usually
begins as a non-cancerous polyp on the inner lining of the colon or
rectum. A tumor is abnormal tissue and can be benign (not cancer) or
malignant (cancer). A polyp is a benign, non-cancerous tumor. Some
polyps can change into cancer, but not all do. The chance of changing
into a cancer depends upon the kind of polyp:
- Adenomatous
polyps (adenomas) are polyps that have the potential to
change into cancer. Because of this, adenomas are called a
pre-cancerous condition.
- Hyperplastic
polyps and inflammatory polyps, in general, are not
pre-cancerous. But some doctors think that some hyperplastic polyps can
become pre-cancerous or might be a sign of having a greater risk of
developing adenomas and cancer, particularly when these polyps grow in
the ascending colon.
Another kind of pre-cancerous condition is called dysplasia.
Dysplasia is an area in the lining of the colon or rectum where the
cells look abnormal (but not like true cancer cells) when viewed under
a microscope. These cells can change into cancer over time. Dysplasia
is usually seen in people who have had diseases such as ulcerative
colitis or Crohn's disease for many years. Both ulcerative colitis and
Crohn's disease cause chronic inflammation of the colon.
Start and spread of colorectal cancer
If cancer forms within a polyp, it can eventually begin to
grow into the wall of the colon or rectum. When cancer cells are in the
wall, they can then grow into blood vessels or lymph vessels. Lymph
vessels are thin, tiny channels that carry away waste and fluid. They
first drain into nearby lymph nodes, which are bean-shaped structures
that help fight infections. Once cancer cells spread into blood or
lymph vessels, they can travel to distant parts of the body, such as
the liver. This process of spread is called metastasis.
Types of cancer in the colon and rectum
Several types of cancer can start in the colon or rectum.
Adenocarcinomas
More than 95% of colorectal cancers are a type of cancer known
as adenocarcinomas. These cancers start in cells that form glands that
make mucus to lubricate the inside of the colon and rectum. When
doctors speak of colorectal cancer, this is almost always what they are
referring to.
Other, less common types of tumors may also develop in the
colon and rectum. These include:
Carcinoid tumors
These tumors develop from specialized hormone-producing cells
of the intestine. They are discussed in the separate American Cancer
Society document, Gastrointestinal Carcinoid Tumors.
Gastrointestinal stromal tumors (GISTs)
These tumors develop from specialized cells in the wall of the
colon called the "interstitial cells of Cajal." Some are benign
(non-cancerous); others are malignant (cancerous). Although these
tumors can be found anywhere in the digestive tract, they are unusual
in the colon. They are discussed in the separate American Cancer
Society document, Gastrointestinal Stromal Tumors.
Lymphomas
These are cancers of immune system cells that typically
develop in lymph nodes, but they may also start in the colon and rectum
or other organs. Information on lymphomas of the digestive system is
included in the separate American Cancer Society document, Non-Hodgkin Lymphoma.
The remainder of this document focuses only on colorectal
adenocarcinomas.
Importance of colorectal cancer screening
Excluding skin cancers, colorectal cancer is the third most
common cancer diagnosed in both men and women in the United States. The
American Cancer Society's most recent estimates for the number of
colorectal cancer cases in the United States are for 2009:
- 106,100 new cases of colon cancer (52,010 in men and 54,090
in women)
- 40,870 new cases of rectal cancer (23,580 in men and 17,290
in women)
Overall, the lifetime risk for developing colorectal cancer is
about 1 in 19 (5.3%). This risk is slightly higher in men than in
women. A number of other factors (described in the section, "Risk factors for
colorectal cancer") may also affect a person's risk for
developing colorectal cancer.
Colorectal cancer is the third leading cause of cancer-related
deaths in the United States when men and women are considered
separately, and the second leading cause when both sexes are combined.
It is expected to cause about 49,920 deaths (25,240 in men and 24,680
in women) during 2009.
The death rate (the number of deaths per 100,000 people per
year) from colorectal cancer has been dropping for more than 20 years.
There are a number of likely reasons for this. One is that polyps are
being found by screening and removed before they can develop into
cancers. Screening is also allowing more colorectal cancers to be found
earlier, when the disease is easier to cure. In addition, treatment for
colorectal cancer has improved over the last several years. As a
result, there are now more than 1 million survivors of colorectal
cancer in the United States.
Regular colorectal cancer screening or testing is one of the
most powerful weapons for preventing colorectal cancer. Screening is
the process of looking for cancer in people who have no symptoms of the
disease.
From the time the first abnormal cells start to grow into
polyps, it usually takes about 10 to 15 years for them to develop into
colorectal cancer. Regular screening can, in many cases, prevent
colorectal cancer altogether. This is because some polyps, or growths,
can be found and removed before they have the chance to turn into
cancer. Screening can also result in finding colorectal cancer early,
when it is highly curable.
Several tests are used to screen for colorectal cancer in
people with an average risk of colorectal cancer. Ask your doctor which
tests are available where you live and which options might be right for
you.
People who have no identified risk factors (other than age)
should begin regular screening at age 50. Those who have a family
history or other risk factors for colorectal polyps or cancer (see
below) should talk with their doctor about starting screening at a
younger age and/or getting screened more frequently.
Risk
factors for colorectal cancer
A risk factor is anything that affects your chance of getting
a disease such as cancer. Different cancers have different risk
factors. For example, exposing skin to strong sunlight is a risk factor
for skin cancer, and smoking is a risk factor for cancers of the lungs,
larynx (voice box), mouth, throat, esophagus, kidneys, bladder, colon,
and several other organs.
But risk factors don't tell us everything. Having a risk
factor, or even several risk factors, does not mean that you will get
the disease. And some people who get the disease may not have any known
risk factors. Even if a person with colorectal cancer has a risk
factor, it is often very hard to know how much that risk factor may
have contributed to the cancer.
Researchers have found several risk factors that may increase
a person's chance of developing colorectal polyps or colorectal cancer.
Risk factors you cannot change
Age
While younger adults can develop colorectal cancer, the
chances of developing colorectal cancer increase markedly after age 50.
More than 90% of people diagnosed with colorectal cancer are older than
50.
Personal history of colorectal polyps or colorectal cancer
If you have a history of adenomatous polyps (adenomas), you
are at increased risk of developing colorectal cancer. This is
especially true if the polyps are large or if there are many of them.
If you have had colorectal cancer, even though it has been
completely removed, you are more likely to develop new cancers in other
areas of the colon and rectum. The chances of this happening are
greater if you had your first colorectal cancer when you were younger.
Personal history of inflammatory bowel
disease
Inflammatory bowel disease (IBD), which includes ulcerative colitis
and Crohn's disease,
is a condition in which the colon is inflamed over a long period of
time. If you have IBD, your risk of developing colorectal cancer is
increased, and you need to be screened for colorectal cancer on a more
frequent basis.
People who have had IBD for many years often develop
dysplasia. Dysplasia is a term used to describe cells in the lining of
the colon or rectum that look abnormal (but not like true cancer cells)
when viewed under a microscope. These cells can change into cancer over
time.
Inflammatory bowel disease is different from irritable bowel syndrome (IBS),
which does not carry an increased risk for colorectal cancer.
Family history of colorectal cancer
Most colorectal cancers occur in people without a family
history of colorectal cancer. Still, as many as 1 in 5 people who
develop colorectal cancer have other family members who have been
affected by this disease.
Those with a history of colorectal cancer or adenomatous
polyps in one or more first-degree relatives (parents, siblings, or
children) are at increased risk. The risk is about doubled in those
with a single affected first-degree relative. It is even higher if the
first-degree relative is younger than 60, or if more than one
first-degree relative is affected.
The reasons for the increased risk are not clear in all cases.
Cancers can "run in the family" because of inherited genes, shared
environmental factors, or some combination of these.
People with a family history of adenomatous polyps or
colorectal cancer should talk with their doctor about the possible need
to begin screening before age 50. If you have had adenomatous polyps or
colorectal cancer, it's important to tell your close relatives so that
they can pass along that information to their doctors and start
screening at the right age.
Inherited syndromes
About 5% of people who develop colorectal cancer have an
inherited genetic susceptibility to the disease. The 2 most common
inherited syndromes linked with colorectal cancers are familial
adenomatous polyposis (FAP) and hereditary non-polyposis colorectal
cancer (HNPCC).
Familial
adenomatous polyposis (FAP): FAP is caused by changes
(mutations) in the APC gene that a person inherits from his or her
parents. About 1% of all colorectal cancers are due to FAP.
People with this disease typically develop hundreds or
thousands of polyps in their colon and rectum, usually in their teens
or early adulthood. Cancer usually develops in 1 or more of these
polyps as early as age 20. By age 40, almost all people with this
disorder will have developed cancer if preventive surgery (removing the
colon) is not done.
FAP is sometimes associated with Gardner syndrome, a condition
that also involves benign (non-cancerous) tumors of the skin, soft
connective tissue, and bones.
Hereditary
non-polyposis colon cancer (HNPCC): HNPCC, also known as
Lynch syndrome, accounts for about 3% to 4% of all colorectal cancers.
HNPCC can be caused by inherited changes in a number of different genes
that normally help repair DNA damage.
This syndrome also develops when people are relatively young.
People with HNPCC have polyps, but they only have a few, not hundreds
as in FAP. The lifetime risk of colorectal cancer in people with this
condition may be as high as 70% to 80%.
Women with this condition also have a very high risk of
developing cancer of the endometrium (lining of the uterus). Other
cancers linked with HNPCC include cancer of the ovary, stomach, small
bowel, pancreas, kidney, ureters (tubes that carry urine from the
kidneys to the bladder), and bile duct.
For more information on HNPCC, see the sections "Do
we know what causes colorectal cancer?" and "Can
colorectal cancer be prevented?" in our larger Colorectal Cancer
document.
Turcot syndrome:
This is a rare inherited condition in which people are at increased
risk of adenomatous polyps and colorectal cancer, as well as brain
tumors. There are actually 2 types of Turcot syndrome:
- One can be caused by gene changes similar to those seen in
FAP, in which cases the brain tumors are medulloblastomas.
- The other can also be caused by gene changes similar to
those seen in HNPCC, in which cases the brain tumors are glioblastomas.
Peutz-Jeghers
syndrome: People with this rare inherited condition tend
to have freckles around the mouth (and sometimes on their hands and
feet) and large polyps in their digestive tracts. They are at a greatly
increased risk for colorectal cancer, as well as several other cancers,
which usually appear at a younger age than usual.
Identifying families with these inherited syndromes is
important because it allows doctors to recommend specific steps, such
as screening and other preventive measures when the family members are
younger.
Because several types of cancer can be linked with these
syndromes, it's important to check your family medical history for
polyps or any type of cancer. If you have had adenomatous polyps or
cancer, it's important to tell your close relatives. People with a
family history of colorectal polyps or cancer should consider genetic
counseling to review their family medical tree and determine whether
genetic testing may be right for them. If needed, this can help them
decide about getting screened and treated at an early age.
Racial and ethnic background
African Americans have the highest colorectal cancer incidence
and mortality rates of all racial groups in the United States. The
reason for this is not yet understood.
Jews of Eastern European descent (Ashkenazi Jews) have one of
the highest colorectal cancer risks of any ethnic group in the world.
Several gene mutations leading to an increased risk of colorectal
cancer have been found in this group. The most common of these DNA
changes, called the I1307K APC mutation, is present in about 6% of
American Jews.
Lifestyle-related factors
Several lifestyle-related factors have been linked to
colorectal cancer. In fact, the links between diet, weight, and
exercise and colorectal cancer risk are some of the strongest for any
type of cancer.
Certain types of diets
A diet that is high in red meats (beef, pork, lamb) and
processed meats (hot dogs and some luncheon meats) can increase
colorectal cancer risk. Methods of cooking meats at very high
temperatures (frying, broiling, or grilling) create chemicals that
might increase cancer risk, although it's not clear how much this might
contribute to an increase in colorectal cancer risk. Diets high in
vegetables and fruits have been linked with decreased risk of
colorectal cancer. Whether other dietary components (fiber, certain
types of fats, etc.) affect colorectal cancer risk is not clear.
Physical inactivity
If you are not physically active, you have a greater chance of
developing colorectal cancer. Increasing activity may help reduce your
risk.
Obesity
If you are very overweight, your risk of developing and dying
from colorectal cancer is increased. Although obesity raises the risk
of colon cancer in both men and women, the link seems to be stronger in
men.
Smoking
Long-term smokers are more likely than non-smokers to develop
and die from colorectal cancer. Smoking is a well-known cause of lung
cancer, but some of the cancer-causing substances are swallowed and can
cause digestive system cancers, such as colorectal cancer.
Heavy alcohol use
Colorectal cancer has been linked to the heavy use of alcohol.
At least some of this may be due to the fact that heavy alcohol users
tend to have low levels of folic acid in the body. Still, it would be
wise to limit alcohol use to no more than 2 drinks a day for men and 1
drink a day for women.
Type 2 diabetes
People with type 2 (usually non-insulin dependent) diabetes
have an increased risk of developing colorectal cancer. Both type 2
diabetes and colorectal cancer share some of the same risk factors
(such as excess weight). But even after taking these into account,
people with type 2 diabetes still have an increased risk. They also
tend to have a less favorable prognosis (outlook) after diagnosis.
Factors with uncertain, controversial, or
unproven effects on colorectal cancer
Night shift work
Results of one study suggested working a night shift at least
3 nights a month for at least 15 years may increase the risk of
colorectal cancer in women. The study authors suggested this might be
due to changes in levels of melatonin (a hormone that responds to
changes in light) in the body. More research is needed to confirm or
refute this finding.
Previous treatment for certain cancers
Some studies have found that men who survive testicular cancer
seem to have a higher rate of colorectal cancer and some other cancers.
This might be due to the treatments they have received.
Several studies have suggested that men who received radiation
therapy to treat prostate cancer may have a higher risk of rectal
cancer, because the rectum receives some radiation during treatment.
Most of these studies are based on men treated in the 1980s and 1990s,
and the effect of more modern radiation methods on rectal cancer risk
is not clear. There are many possible side effects of prostate cancer
treatment that men should consider when making treatment decisions.
Some doctors recommend that the risk of rectal cancer be considered as
one of those possible side effects.
The American Cancer Society and several other medical
organizations recommend earlier screening for people with an increased
colorectal cancer risk. These recommendations differ from those for
people at average risk. For more information, speak with your doctor
and refer to the tables below.
Finding colorectal cancer early
While colorectal cancer is often found after symptoms appear,
most people with early colon or rectal cancer have no symptoms of the
disease. Symptoms usually appear only with more advanced disease. This
is why getting the recommended screening tests (as described in the
next section) before any symptoms develop is so important.
If your doctor finds something suspicious during a screening
exam, or if you have any of the symptoms of colorectal cancer described
below, your doctor will probably recommend exams and test to find the
cause.
Signs and symptoms of colorectal cancer
If you have any of the following you should see your doctor:
- a change in bowel habits, such as diarrhea, constipation,
or narrowing of the stool, that lasts for more than a few days
- a feeling that you need to have a bowel movement that is
not relieved by doing so
- rectal bleeding, dark stools, or blood in the stool (often,
though, the stool will look normal)
- cramping or abdominal (stomach area) pain
- weakness and fatigue
Most of these symptoms are more likely to be caused by
conditions other than colorectal cancer, such as infection,
hemorrhoids, or inflammatory bowel disease. Still, if you have any of
these problems, it's important to see your doctor right away so the
cause can be found and treated, if needed.
Colorectal cancer screening tests
Screening is the process of looking for cancer in people who
have no symptoms of the disease. Several different tests can be used to
screen for colorectal cancers. These tests can be divided into 2 broad
groups:
- Tests that
can find both colorectal polyps and cancer: These tests
look at the structure of the colon itself to find any abnormal areas.
This is done either with a scope inserted into the rectum or with
special imaging (x-ray) tests. Polyps found before they become
cancerous can be removed, so these tests may prevent colorectal cancer.
Because of this, these tests are preferred if they are available and
you are willing to have them.
- Tests that
mainly find cancer: These involve testing the stool
(feces) for signs that cancer may be present. These tests are less
invasive and easier to have done, but they are less likely to detect
polyps.
These tests as well as others can also be used when people
have symptoms of colorectal cancer and other digestive diseases.
Tests that can find both colorectal polyps
and cancer
Flexible sigmoidoscopy
During this test, the doctor looks at part of the colon and
rectum with a sigmoidoscope -- a flexible, lighted tube about the
thickness of a finger with a small video camera on the end. It is
inserted through the rectum and into the lower part of the colon.
Images from the scope are viewed on a display monitor.
Using the sigmoidoscope, your doctor can view the inside of
the rectum and part of the colon to detect (and possibly remove) any
abnormality. Because the sigmoidoscope is only 60 centimeters (about 2
feet) long, the doctor is able to see the entire rectum but less than
half of the colon with this procedure.
Before the test:
You will need to have a bowel preparation to clean out your lower
colon. The colon and rectum must be empty and clean so your doctor can
view the lining of the sigmoid colon and rectum. Your doctor will give
you specific instructions to follow. Be sure your doctor is aware of
any medicines you are taking, as you may need to change how you take
them before the test. You may be asked to follow a special diet (such
as drinking only clear liquids) for a day before the exam. You may also
be asked to use enemas or to use strong laxatives to clean out your
colon before the exam.
During the test:
A sigmoidoscopy usually takes 10 to 20 minutes. Most
people do not need to be sedated for this test, but this may be an
option you can discuss with your doctor. Sedation may make the test
less uncomfortable, but it requires some time to recover from it, as
well as having someone with you to take you home after the test.
You will likely be placed on a table on your left side with
your knees positioned near your chest. Your doctor should do a digital
rectal exam (DRE) before inserting the sigmoidoscope. The sigmoidoscope
is lubricated to make it easier to insert into the rectum. The scope
may feel cold. The sigmoidoscope may stretch the wall of the colon,
which may cause bowel spasms or lower abdominal pain. Air will be
placed into the sigmoid colon through the sigmoidoscope so the doctor
can see the colon better. During the procedure, you might feel pressure
and slight cramping in your lower abdomen. To ease discomfort and the
urge to have a bowel movement, it helps to breathe deeply and slowly
through your mouth. You will feel better after the test once the air
leaves your colon.
If a small polyp is found during the test your doctor may
remove it with a small instrument passed through the scope. The polyp
will be sent to a lab to be looked at by a pathologist. If a
pre-cancerous polyp (an adenoma) or colorectal cancer is found during
the test, you will need to have a colonoscopy at a later date to look
for polyps or cancer in the rest of the colon.
Possible
complications and side effects: This test may be
uncomfortable because of the air put into the colon, but it should not
be painful. Be sure to let your doctor know if you feel pain during the
procedure. You may see a small amount of blood in your first bowel
movement after the test. Significant bleeding and puncture of the colon
are possible complications, but they are very uncommon.
Colonoscopy
For this test, the doctor looks at the entire length of the
colon and rectum with a colonoscope, which is basically a longer
version of a sigmoidoscope. It is inserted through the rectum into the
colon. The colonoscope has a video camera on the end that is connected
to a display monitor so the doctor can see and closely examine the
inside of the colon. Special instruments can be passed through the
colonoscope to remove (biopsy) any suspicious looking areas such as
polyps, if needed.
Colonoscopy may be done in a hospital outpatient department,
in a clinic, or in a doctor's office.
Before the test:
Be sure your doctor is aware of any medicines you are taking, as you
may need to change how you take them before the test. The colon and
rectum must be empty and clean so your doctor can view their inner
linings during the test. You will need to take laxatives (liquids,
pills, or both) the day before the test and possibly an enema that
morning. Your doctor will give you specific instructions. It is
important to read these carefully a few days ahead of time, since you
may need to shop for special supplies and get laxatives from a
pharmacy. If you are not sure about any of the instructions, call the
doctor's office and go over them step by step with the nurse. Many
people consider the bowel preparation to be the most unpleasant part of
the test, as it usually requires you to be in the bathroom quite a bit.
You may be given other instructions as well. For example, your
doctor may instruct that you drink only clear liquids (water, apple or
cranberry juice, and any gelatin except red or purple) for a day or 2
before the exam. Plain tea or coffee with sugar is usually okay, but no
milk or creamer is allowed. Clear broth, ginger ale, and most soft
drinks or sports drinks are usually allowed unless they have red or
purple food colorings, which could be mistaken for blood in the colon.
You will likely also be told not to eat or drink anything
after midnight the night before your test. If you normally take
prescription medicines in the mornings, talk with your doctor or nurse
about how to manage them for the day.
You may need to arrange for someone to drive you home from the
test because the sedative used during the test can affect your ability
to drive. Depending on the medicines used, some doctors require that
someone drive you home.
During the test:
The test itself usually takes about 30 minutes, although it may take
longer if a polyp is found and removed. Before the colonoscopy begins,
you will be given a sedating medicine (usually through your vein) to
make you feel comfortable and sleepy during the procedure. You will
probably be awake, but you may not be aware of what is going on and may
not remember the procedure afterward. Most people will be fully awake
by the time they get home from the test.
During the procedure, you will be placed on your side with
your knees flexed and a drape will cover you. Your blood pressure,
heart rate, and breathing rate will be monitored during and after the
test.
Your doctor should do a digital rectal exam (DRE) before
inserting the colonoscope. The colonoscope is lubricated so it can be
easily inserted into the rectum. Once in the rectum, the colonoscope is
passed all the way to the beginning of the colon, called the cecum. If
you are not sedated, you may feel an urge to have a bowel movement when
the colonoscope is inserted or pushed further up the colon. To ease any
discomfort it may help to breathe deeply and slowly through your mouth.
The colonoscope will deliver air into the colon so that it is easier
for the doctor to see the lining of the colon and use the instruments
to perform the test. Suction will be used to remove any blood or liquid
stools.
The doctor will look at the inner walls of the colon as he or
she slowly withdraws the colonoscope. If a small polyp is found, the
doctor may remove it. Some small polyps may eventually become
cancerous. For this reason, they are usually removed. This is usually
done by passing a wire loop through the colonoscope to cut the polyp
from the wall of the colon with an electrical current. The polyp can
then be sent to a lab to be checked under a microscope to see if it has
any areas that have changed into cancer.
If your doctor sees a larger polyp or tumor or anything else
abnormal, a biopsy may be done. For this procedure, a small piece of
tissue is taken out through the colonoscope. The tissue is looked at
under a microscope to determine if it is a cancer, a benign
(non-cancerous) growth, or a result of inflammation.
Possible side
effects and complications: The bowel preparation before
the test can be unpleasant. The test itself may be uncomfortable, but
the sedative usually prevents this, and most people feel normal once
the effects of the sedative wear off. Some people may have gas pains or
cramping for a while after the test.
In some cases, people may have low blood pressure or changes
in heart rhythms due to the sedation during the test, although these
are rarely serious.
If a polyp is removed or a biopsy is done during the
colonoscopy, you may notice some blood in your stool for a day or 2
after the test. Significant bleeding is slightly more likely with
colonoscopy than with sigmoidoscopy, but it is still uncommon. In rare
cases, continued bleeding might require treatment.
Although colonoscopy is a safe procedure, on rare occasions
the colonoscope can puncture the wall of the colon or rectum. This is
called a perforation. It can be a serious complication and at times
requires surgical repair. Talk to your doctor about the risk of this
complication.
Double-contrast barium enema
The double-contrast barium enema (DCBE) is also called an air-contrast barium enema
or a barium enema with
air contrast. It is basically a type of x-ray test. Barium
sulfate, which is a chalky liquid, and air are used to outline the
inner part of the colon and rectum to look for abnormal areas on
x-rays. If suspicious areas are seen on this test, a colonoscopy will
be needed to explore them further.
Before the test:
As with colonoscopy, it is very important that the colon
and rectum are empty and clean so your doctor can see them during the
test. Your doctor will give you specific instructions on preparing for
the test. Be sure to follow them. For example, you may be asked to
clean your bowel the night before with laxatives and/or take an enema
the morning of the exam. You will likely be asked to follow a clear
liquid diet for a day or 2 before the procedure. You may also be told
to avoid eating or drinking dairy products the day before the test, and
to not eat or drink anything after midnight on the night before the
procedure. Many people consider the bowel preparation to be the most
unpleasant part of the test, as it usually requires you to be in the
bathroom quite a bit.
During the test:
The procedure takes about 30 to 45 minutes, and it does
not require sedation. For this test, you lie on a table on your side in
an x-ray room. A small, flexible tube is inserted into the rectum, and
barium sulfate is pumped in to partially fill and open up the colon.
When the colon is about half-full of barium, you are turned on the
x-ray table so the barium spreads throughout the colon. Then air is
pumped into the colon through the same tube to make it expand. This may
cause some discomfort, and you may feel the urge to have a bowel
movement.
X-ray pictures of the lining of your colon are then taken,
allowing the doctor to identify polyps or cancers. You may be asked to
change positions so that different views of the colon and rectum can be
seen on the x-rays.
If polyps or other suspicious areas are seen on this test, a
colonoscopy will likely be needed to remove them or to explore them
fully.
Possible side
effects and complications: You may have bloating or
cramping after the test, and will likely feel the need to empty your
bowels soon after the test is done. The barium can cause constipation
for a few days, and your stool may appear grey or white until the
barium leaves the body. There is a very small risk that inflating the
colon with air could injure or puncture the colon, but this risk is
thought to be much less than with colonoscopy.
CT colonography (virtual colonoscopy)
This test is an advanced type of computed tomography (CT or
CAT) scan of the colon and rectum. A CT scan is an x-ray test that
produces detailed cross-sectional images of your body. Instead of
taking one picture, like a regular x-ray, a CT scanner takes many
pictures as it rotates around you while you lie on a table. A computer
then combines these pictures into images of slices of the part of your
body being studied. For CT colonography, special computer programs
create both two-dimensional x-ray pictures and a three-dimensional
"fly-through" view of the inside of the colon and rectum, which allows
the doctor to look for polyps or cancer.
This test may be especially useful for some people who can't
have or don't want to have more invasive tests such as colonoscopy. It
can be done fairly quickly and does not require sedation. But even
though this test is not invasive like colonoscopy, it still requires
the same type of bowel preparation and uses a tube placed in the rectum
(similar to the tube used for barium enema) to fill the colon with air.
Another possible drawback is that if polyps or other suspicious areas
are seen on this test, a colonoscopy will still probably be needed to
remove them or to explore them fully.
Before the test:
It is important that the colon and rectum are emptied before this test
to provide the best images. Because of this, the preparation for this
test is similar to that for a double-contrast barium enema or
colonoscopy. You will likely be told to follow a clear liquid diet for
a day or 2 before the test. You will also be given instructions for
taking strong laxatives and/or enemas the night before or morning of
the exam. This will probably require you to be in the bathroom quite a
bit.
During the test:
This test is done in a special room with a CT scanner, and
takes about 10 minutes. You may be asked to drink a contrast solution
before the test to help "tag" any remaining stool in the colon or
rectum, which helps the doctor when looking at the test images. You
will be asked to lie in a thin table that is part of the CT scanner,
and will have a small, flexible tube inserted into your rectum. Air is
pumped through the tube into the colon to expand it to provide better
images. The table then slides into the CT scanner, and you will be
asked to hold your breath while the scan takes place. You will likely
have 2 scans: one while you are lying on your back and one while you
are on your stomach. Each scan typically takes only about 10 to 15
seconds.
Possible side
effects and complications: There are usually very few side
effects after CT colonography. You may feel bloated or have cramps
because of the air in the colon, but this should go away once the air
passes from the body. There is a very small risk that inflating the
colon with air could injure or puncture the colon, but this risk is
thought to be much less than with colonoscopy.
Tests that mainly find colorectal cancer
These tests examine the stool to look for signs of cancer.
Most people find these tests to be easier because they are not invasive
and can often be done at home. But they are not as good at detecting
polyps as the tests described above, and a positive result on one of
these screening tests will likely require a more invasive test such as
colonoscopy.
Fecal occult blood test
The fecal occult blood test (FOBT) is used to find occult
(hidden) blood in feces. The idea behind this test is that blood
vessels at the surface of larger colorectal polyps or cancers are often
fragile and easily damaged by the passage of feces. The damaged vessels
usually release a small amount of blood into the feces, but only rarely
is there enough bleeding to be noticeable in the stool.
The FOBT detects blood in the stool through a chemical
reaction. This test cannot tell whether the blood is from the colon or
from other portions of the digestive tract (such as the stomach). If
this test is positive, a colonoscopy is needed to see if there is a
cancer, polyp, or other cause of bleeding such as ulcers, hemorrhoids,
diverticulosis (tiny pouches that form at weak spots in the colon
wall), or inflammatory bowel disease (colitis).
This screening test is done with a take-home kit that you can
use in the privacy of your own home. An FOBT done during a digital
rectal exam in the doctor's office is not sufficient for screening.
In order to be beneficial the test must be repeated every year.
People having this test will receive a kit with instructions
from their doctor's office or clinic. The kit will explain how to take
a stool or feces sample at home (usually specimens from 3 consecutive
bowel movements that are smeared onto small squares of paper). The kit
should then be returned to the doctor's office or medical lab (usually
within 2 weeks) for testing. See below for more details.
Before the test:
Some foods or drugs can affect the test, so your doctor may suggest
that you try to avoid the following before this test:
- non-steroidal anti-inflammatory drugs (NSAIDs), such as
ibuprofen (Advil), naproxen (Aleve), or aspirin (more than 1 adult
aspirin per day), for 7 days before testing. (They can cause bleeding,
which can lead to a false-positive result.) Acetaminophen (Tylenol) can
be taken as needed.
- vitamin C in excess of 250 mg daily from either supplements
or citrus fruits and juices for 3 days before testing. (This can affect
the chemicals in the test and make it show negative.)
- red meats (beef, lamb, or liver) for 3 days before testing.
(Components of blood in the meat may cause the test to show positive.)
Some people who are given the test never do it or don't give
it to their doctor because they worry that something they ate may
interfere with the test. For this reason, many doctors tell their
patients it isn't essential to follow any restrictions in their diet.
The most important thing is to get the test done. People should try to
avoid taking aspirin or related drugs for minor aches. But if you take
these medicines daily for heart problems or other conditions, don't
stop them for this test without approval from your doctor.
Collecting the
samples: Have all of your supplies ready and in one
place. Supplies will include a test kit, test cards, either a brush or
wooden applicator, and a mailing envelope. The kit will give you
detailed instructions on how to collect the specimen. The instructions
below can be used as a guide, but your kit instructions might be a
little different. Always follow the instructions on your kit.
- You will need to collect a sample from your bowel movement.
You can place a sheet of plastic wrap loosely across the toilet bowl to
catch the stool or you can use a dry container to collect the stool. Do
not let the stool specimen mix with urine. After you obtain a sample,
you can flush the remaining stool down the toilet.
- Use a wooden applicator or a brush to smear a thin film of
the stool sample onto one of the slots in the test card or slide.
- Next, collect a specimen from a different area of the same
stool and smear a thin film of the sample onto the other slot in the
test card or slide.
- Close the slots and put your name and the date on the test
kit. Store the kit overnight in a paper envelope to allow it time to
dry.
- Repeat the test on your next 2 bowel movements if
instructed. Most tests require collecting more than one sample from
different bowel movements. This improves the accuracy of the test
because many cancers don't bleed all of the time, and blood may not be
present in all stool samples.
- Place the test kit in the mailing pouch provided and return
it to your doctor or lab as soon as possible (but within 14 days of
taking the first sample).
If this test finds blood, a colonoscopy will be needed to look
for the source. It is not sufficient to simply repeat the FOBT or
follow up with other types of tests.
Fecal immunochemical test
The fecal immunochemical test (FIT), also called an
immunochemical fecal occult blood test (iFOBT), is a newer kind of test
that also detects occult (hidden) blood in the stool. This test reacts
to part of the human hemoglobin protein, which is found on red blood
cells.
The FIT is done essentially the same way as the FOBT, but some
people may find it easier to use because there are no drug or dietary
restrictions (vitamins or foods do not affect the FIT) and sample
collection may take less effort. This test is also less likely to react
to bleeding from parts of the upper digestive tract, such as the
stomach.
As with the FOBT, the FIT may not detect a tumor that is not
bleeding, so multiple stool samples should be tested. And if the
results are positive for hidden blood, a colonoscopy is required to
investigate further. In order to be beneficial the test must be
repeated every year.
Collecting the
samples: Have all of your supplies ready and in one
place. Supplies will include a test kit, test cards, long brushes,
waste bags, and a mailing envelope. The kit will give you detailed
instructions on how to collect the specimen. The instructions below can
be used as a guide, but the instructions on your kit might be a little
different. Always follow the instructions on your kit.
- Flush the toilet before your bowel movement. After you go,
place used toilet paper in the waste bag from the kit, not in the
toilet.
- Brush the surface of the stool with one of the brushes,
then dip the brush in the toilet water. Dab the end of the brush onto
one of the slots in the test card or slide.
- Close the slot and put your name and the date on the test
kit.
- Repeat the test on your next bowel movement if instructed.
Most tests require collecting more than one sample from different bowel
movements. This improves the accuracy of the test because many cancers
don't bleed all of the time, and blood may not be present in all stool
samples.
- Place the test kit in the mailing envelope provided and
return it to your doctor or lab as soon as possible (but within 14 days
of taking the first sample).
Stool DNA tests
Instead of looking for blood in the stool, these tests look
for certain abnormal sections of DNA (genetic material) from cancer or
polyp cells. Colorectal cancer cells often contain DNA mutations
(changes) in certain genes. Cells from colorectal cancers or polyps
with these mutations are often shed into the stool, where tests may be
able to detect them.
This is a newer type of test, and the best length of time to
go between tests is not yet clear. This test is also much more
expensive than other forms of stool testing.
This test is not invasive and doesn't require any special
preparation. But as with other stool tests, if the results are
positive, a colonoscopy is required to investigate further.
People having this test will receive a kit with detailed
instructions from their doctor's office or clinic on how to collect the
specimen. Always follow the instructions on your kit.
This test requires an entire stool sample. It is obtained
using a special container, which is placed in a bracket that stretches
across the seat of the toilet. You have your bowel movement while
sitting on the toilet, making sure it goes into the container. You then
place the container and an ice pack in a shipping box and close and
label the box. The specimen must be shipped to the lab within 24 hours
of having the bowel movement.
What are some of the pros and cons of these
screening tests?
|
Test
|
Pros
|
Cons
|
|
Flexible Sigmoidoscopy
|
Fairly quick and safe
Usually doesn't require full bowel preparation
Sedation usually not used
Does not require a specialist
Done every 5 years
|
Views only about a third of the colon
Can miss small polyps
Can't remove all polyps
May be some discomfort
Done in a doctor’s office, clinic, or
hospital
Very small risk of bleeding, infection, or bowel tear
Colonoscopy will be needed if abnormal
|
|
Colonoscopy
|
Can usually view entire colon
Can biopsy and remove polyps
Done every 10 years
Can diagnose other diseases
|
Can miss small polyps
Full bowel preparation needed
More expensive on a one-time basis than other forms of
testing
Sedation of some kind is usually needed
Will need someone to drive you home
You may miss a day of work
Small risk of bleeding, bowel tears, or infection
|
|
Double Contrast Barium Enema (DCBE)
|
Can usually view entire colon
Relatively safe
Done every 5 years
No sedation needed
|
Can miss small polyps
Full bowel preparation needed
Some false positive test results
Cannot remove polyps during testing
Colonoscopy will be needed if abnormal
|
|
CT Colonography (Virtual Colonoscopy)
|
Fairly quick and safe
Can usually view entire colon
Done every 5 years
No sedation needed
|
Can miss small polyps
Full bowel preparation needed
Some false positive test results
Cannot remove polyps during testing
Colonoscopy will be needed if abnormal
Still fairly new - may be insurance issues
|
|
Fecal Occult Blood Test (FOBT)
|
No direct risk to the colon
No bowel preparation
Sampling done at home
Inexpensive
|
May miss many polyps and some cancers
May produce false-positive test results
May have pre-test dietary limitations
Should be done annually
Colonoscopy will be needed if abnormal
|
|
Fecal Immunochemical Test (FIT)
|
No direct risk to the colon
No bowel preparation
No pre-test dietary restrictions
Sampling done at home
Fairly inexpensive
|
May miss many polyps and some cancers
May produce false-positive test results
Should be done annually
Colonoscopy will be needed if abnormal
|
|
Stool DNA Test
|
No direct risk to the colon
No bowel preparation
No pre-test dietary restrictions
Sampling done at home
|
May miss many polyps and some cancers
May produce false-positive test results
More expensive than other stool tests
Still a fairly new test
Not clear how often it should be done
Colonoscopy will be needed if abnormal
|
American Cancer Society recommendations for
colorectal cancer early detection
People at average risk
The American Cancer Society believes that preventing
colorectal cancer (and not just finding it early) should be a major
reason for getting tested. Finding and removing polyps keeps some
people from getting colorectal cancer. Tests that have the best chance
of finding both polyps and cancer are preferred if these tests are
available to you and you are willing to have them.
Beginning at age 50, both men and women at average risk for
developing colorectal cancer should use one of the screening tests
below:
Tests that find polyps and cancer
- flexible sigmoidoscopy every 5 years*
- colonoscopy every 10 years
- double-contrast barium enema every 5 years*
- CT colonography (virtual colonoscopy) every 5 years*
Tests that mainly find cancer
- fecal occult blood test (FOBT) every year*,**
- fecal immunochemical test (FIT) every year*,**
- stool DNA test (sDNA), interval uncertain*
*Colonoscopy
should be done if test results are positive.
**For FOBT or FIT used
as a screening test, the take-home multiple sample method should be
used. A FOBT or FIT done during a digital rectal exam in the doctor's
office is not adequate for screening.
In a digital
rectal examination (DRE), a doctor examines your rectum
with a lubricated, gloved finger. Although a DRE is often included as
part of a routine physical exam, it is not recommended as a stand-alone
test for colorectal cancer. This simple test, which is not usually
painful, can detect masses in the anal canal or lower rectum. By
itself, however, it is not a very sensitive test for detecting
colorectal cancer due to its limited reach.
Doctors often find a small amount of stool when doing a DRE.
However, simply checking stool obtained in this fashion for evidence of
bleeding with a FOBT or FIT is not an acceptable method of screening
for colorectal cancer. Research has shown that this type of stool
examination will miss more than 90% of colon abnormalities, including
most cancers.
People at increased or high risk
If you are at an increased or high risk of colorectal cancer,
you should begin colorectal cancer screening before age 50 and/or be
screened more often. The following conditions place you at higher than
average risk:
- a personal history of colorectal cancer or adenomatous
polyps
- a personal history of inflammatory bowel disease
(ulcerative colitis or Crohns disease)
- a strong family history of colorectal cancer or polyps (see
"Risk factors for colorectal cancer")
- a known family history of hereditary colorectal cancer
syndromes such as familial adenomatous polyposis (FAP) or hereditary
non-polyposis colon cancer (HNPCC)
The table below suggests screening guidelines for those with increased or high risk
of colorectal cancer based on specific risk factors. Some people may
have more than one risk factor. Refer to the table below and discuss
these recommendations with your doctor. Based on your situation and any
risk factors you may have, your doctor can suggest the best screening
option for you, as well as any changes in the schedule based on your
individual risk.
American Cancer Society Guidelines on Screening and
Surveillance for the Early Detection of Colorectal Adenomas and Cancer
in People at Increased Risk or at High Risk
| Risk Category |
Age to Begin |
Recommended Test(s) |
Comment |
| INCREASED
RISK -- Patients With a History of Polyps on Prior Colonoscopy |
| People with small rectal hyperplastic polyps |
Same as those with average risk
|
Colonoscopy, or other screening options at
regular intervals as for those at average risk |
Those with hyperplastic polyposis syndrome are at
increased risk for adenomatous polyps and cancer and should have more
intensive follow-up.
|
| People with 1 or 2 small (less than 1 cm) tubular
adenomas with low-grade dysplasia |
5 to 10 years after the polyps are removed |
Colonoscopy |
Time between tests should be based on other
factors such as prior colonoscopy findings, family history, and patient
and doctor preferences. |
| People with 3 to 10 adenomas, or a large (1 cm +)
adenoma, or any adenomas with high-grade dysplasia or villous features |
3 years after the polyps are removed |
Colonoscopy |
Adenomas must have been completely removed. If
colonoscopy is normal or shows only 1 or 2 small tubular adenomas with
low-grade dysplasia, future colonoscopies can be done every 5 years. |
| People with more than 10 adenomas on a single exam |
Within 3 years after the polyps are removed |
Colonoscopy |
Doctor should consider possibility of genetic
syndrome (such as FAP or HNPCC). |
| People with sessile adenomas that are removed in
pieces |
2 to 6 months after adenoma removal |
Colonoscopy |
If entire adenoma has been removed, further
testing should be based on doctor’s judgment |
| INCREASED
RISK – Patients With Colorectal Cancer |
| People diagnosed with colon or rectal cancer |
At time of colorectal surgery, or can be 3 to 6
months later if person doesn't have cancer spread that can't be removed |
Colonoscopy to view entire colon and remove all
polyps |
If the tumor presses on the colon/rectum and
prevents colonoscopy, CT colonoscopy (with IV contrast) or DCBE may be
done to look at the rest of the colon. |
| People who have had colon or rectal cancer
removed by surgery |
Within 1 year after cancer resection (or 1 year
after colonoscopy to make sure the rest of the colon/rectum was clear) |
Colonoscopy |
If normal, repeat exam in 3 years. If normal
then, repeat exam every 5 years. Time between tests may be shorter if
polyps are found or there is reason to suspect HNPCC. After low
anterior resection for rectal cancer, exams of the rectum may be done
every 3 to 6 months for the first 2 to 3 years to look for signs of
recurrence. |
| INCREASED
RISK – Patients With a Family History |
| Colorectal cancer or adenomatous polyps in any
first-degree relative before age 60, or in 2 or more first-degree
relatives at any age (if not a hereditary syndrome). |
Age 40, or 10 years before the youngest case in
the immediate family, whichever is earlier |
Colonoscopy |
Every 5 years. |
| Colorectal cancer or adenomatous polyps in any
first-degree relative aged 60 or older, or in at least 2 second-degree
relatives at any age |
Age 40 |
Same options as for those at average risk. |
Same intervals as for those at average risk. |
| HIGH
RISK |
| Familial adenomatous polyposis (FAP) diagnosed by
genetic testing, or suspected FAP without genetic testing |
Age 10 to 12 |
Yearly flexible sigmoidoscopy to look for signs
of FAP; counseling to consider genetic testing if it hasn't been done |
If genetic test is positive, removal of colon
(colectomy) should be considered. |
| Hereditary non-polyposis colon cancer (HNPCC), or
an increased risk of HNPCC based on family history without genetic
testing |
Age 20 to 25 years, or 10 years before the
youngest case in the immediate family |
Colonoscopy every 1 to 2 years; counseling to
consider genetic testing if it hasn't been done |
Genetic testing should be offered to first-degree
relatives of people found to have HNPCC mutations by genetic tests. It
should also be offered if 1 of the first 3 of the modified Bethesda
criteria is met.1 |
Inflammatory bowel disease
-Chronic ulcerative colitis
-Crohn's disease |
Cancer risk begins to be significant 8 years
after the onset of pancolitis (involvement of entire large intestine),
or 12 to 15 years after the onset of left-sided colitis |
Colonoscopy every 1 to 2 years with biopsies for
dysplasia |
These people are best referred to a center with
experience in the surveillance and management of inflammatory bowel
disease. |
1The Bethesda criteria can be found
in the "Can
colorectal
cancer be
prevented?" section of our larger Colorectal
Cancer document.
Colorectal cancer screening: State and
federal coverage laws
The benefits of early detection colorectal
cancer screening
Screening can find non-cancerous colorectal polyps and remove
them before they become cancerous. If colorectal cancer does occur,
early detection and treatment dramatically increase chances of
survival.
The relative 5-year survival rate for colorectal cancer, when
diagnosed at an early stage before it has spread is about 90%. But only
about 4 out of 10 colorectal cancers are found at that early stage.
Once the cancer has spread to nearby organs or lymph nodes, the 5-year relative survival
rate goes down, and if cancer has spread to distant organs (like the
liver or lung) the rate is about 11%.
(A standard 5-year survival rate refers to the percentage of
patients who live at least 5 years after their cancer is diagnosed; it
includes people with colorectal cancer who may die of other causes,
such as heart disease. Five-year relative survival rates are adjusted
for patients dying of other diseases, so they reflect the chances of
not dying specifically from colorectal cancer.)
Not only does colorectal cancer screening save lives, but it
also is cost effective. Studies have shown that the cost-effectiveness
of colorectal screening is consistent with many other kinds of
preventive services and is lower than some common interventions. It is
much less expensive to remove a polyp during screening than to try to
treat advanced colorectal cancer. With sharp cost increases possible as
new treatments become standards of care, screening is likely to become
even more cost effective.
What is needed to increase the use of
colorectal cancer screening?
Several colorectal cancer screening tests are available but
only about half of people aged 50 and older have them. Some factors
affecting their use could include lack of public and health
professional awareness of screening tools, financial barriers, and
inadequate health insurance coverage and/or benefits.
The American Cancer Society believes that all people should
benefit from cancer screenings, without regard to health insurance
coverage. Limitations on covered benefits should not block your ability
to benefit from early detection of cancer. To that end, the Society
supports policies that give all people access to and coverage of early
detection screening for cancer. Such policies should be age and risk
appropriate and based on current scientific evidence as outlined in the
American Cancer Society's early detection guidelines.
State activity
A number of states, as well as the District of Columbia, have
passed laws requiring insurance coverage for a full range of colorectal
cancer screening tests. A few other states require coverage of only
certain tests or have agreements among insurers (instead of laws) to
provide coverage for a full range of tests. Still others require that
insurance for testing be offered or available through Medicare
Supplemental Insurance (Medigap) policies or have no laws regarding
coverage.
States that have screening laws that ensure coverage for a
full range of tests*:
- Alaska
- Arkansas
- California
- Colorado
- Connecticut
- Delaware
- Georgia
- Illinois
- Indiana
- Kentucky
- Louisiana
- Maine
- Maryland
- Missouri
- Nebraska
- Nevada
- New Jersey
- New Mexico
- North Carolina
- Oregon
- Pennsylvania
- Rhode Island
- Texas
- Virginia
- Washington
- Washington, D.C.
- West Virginia
States that have screening laws that require insurers to cover
some but not all tests, or where insurers have voluntarily agreed to
cover a full range of tests*:
- Minnesota
- New York
- Vermont
- Wyoming
*Laws on coverage may vary slightly from state to state, so
check with your insurer or your state government to see what is
covered.
In all other states, either there are no laws requiring
insurance coverage, or there are laws that require insurers to offer
(not necessarily provide) coverage.
Medicare coverage
Medicare covers an initial preventive physical exam for all
new Medicare beneficiaries that must occur within one year of enrolling
in Medicare. The "Welcome to Medicare" physical includes referrals for
preventive services already covered under Medicare, including colon
cancer screening tests.
What colorectal cancer screening tests does
Medicare cover?
- fecal occult blood test (FOBT) or fecal immunochemical test
(FIT) yearly for all Medicare beneficiaries 50 years and older
- every 4 years for those at high risk
- every 4 years for those 50 years and older who are at
average risk, but not within 10 years of a previous colonoscopy
- every 2 years for those at high risk (regardless of age)
- every 10 years for those age 50 and older who are at
average risk
- double-contrast barium enema (DCBE) as an alternative if a
doctor determines that its screening value is equal to or better than
flexible sigmoidoscopy or colonoscopy:
- once every 2 years for those at high risk
- once every 4 years for those 50 years and older who are at
average risk
At this time, Medicare does not cover the cost of virtual
colonoscopy or stool DNA tests.
What would a Medicare beneficiary expect to
pay for a colorectal cancer screening test?
- FOBT/FIT: People
age 50 years or older with Medicare pay no coinsurance and no Part B
deductible.
- flexible
sigmoidoscopy: Beneficiary pays coinsurance or copayment.
No Part B deductible unless the test results in the biopsy or removal
of a growth. If the test is done in an outpatient hospital department
or ambulatory surgical center, the beneficiary pays 25% of the Medicare
approved amount.
- colonoscopy: Beneficiary
pays coinsurance or copayment. No Part B deductible unless the test
results in the biopsy or removal of a growth. If the test is done in an
outpatient hospital department or ambulatory surgical center, the
beneficiary pays 25% of the Medicare approved amount.
- DCBE:
Beneficiary pays coinsurance or copayment. No Part B deductible unless
the test results in the biopsy or removal of a growth. If the test is
done in an outpatient hospital department or ambulatory surgical
center, the beneficiary pays 25% of the Medicare approved amount.
Medicaid
States are authorized to cover colorectal screening under
their Medicaid programs. Unlike Medicare, however, there is no federal
assurance that all state Medicaid programs must cover colorectal cancer
screening in people without symptoms. Medicaid coverage for colorectal
cancer screening varies by state. Some states cover fecal occult blood
testing (FOBT), others cover colorectal cancer screening if a doctor
determines the test to be medically necessary, and in some states,
coverage varies according to which Medicaid managed care plan a person
is enrolled.
Additional resources
More information from your American Cancer
Society
The following related information may also be helpful to you.
These materials may be viewed on our Web site or ordered from our
toll-free number, 1-800-227-2345.
The following books are available from the American Cancer
Society. Call us at 1-800-ACS-2345 to ask about costs or to place your
order.
National organizations and Web sites*
In addition to the American Cancer Society, other sources of
patient information and support include:
American College
of Gastroenterology
Web site: www.acg.gi.org
American
Gastroenterological Association
Web site: www.gastro.org
American Society
of Colon and Rectal Surgeons
Web site: www.fascrs.org
C3: Colorectal
Cancer Coalition
Toll-free number: 1-877-4CRC-111 (1-877-427-2111)
Web site: www.fightcolorectalcancer.org
Centers for
Medicare & Medicaid Services
Web site: www.cms.hhs.gov
Colon Cancer
Alliance
Toll-free number: 1-877-422-2030
Web site: www.ccalliance.org
National Cancer
Institute
Toll-free number: 1-800-422-6237 (1-800-4-CANCER); TYY: 1-800-332-8615
Web site: www.cancer.gov
National
Colorectal Cancer Research Alliance
Web site: www.eif.nccra.org
*Inclusion on
this list does not imply endorsement by the
American Cancer Society.
No matter who you are, we can help. Contact us anytime, day or
night, for information and support. Call us at 1-800-ACS-2345 or
visit
www.cancer.org.
References
American Cancer Society. Cancer
Facts & Figures 2009.
Atlanta, Ga: American Cancer Society; 2009.
American Cancer Society. Cancer
Prevention & Early
Detection Facts & Figures 2009. Atlanta, Ga:
American Cancer
Society; 2009.
American Cancer Society. Colorectal
Cancer Facts &
Figures 2008-2010. Atlanta, Ga: American Cancer Society;
2008.
American Cancer Society. Detailed Guide: Colon and Rectum
Cancer. 2009. Accessed at
www.cancer.org/docroot/CRI/CRI_2_3x.asp?dt=10.
Centers for Medicare and Medicaid Services. Colon Cancer
Screening. 2008. Accessed at www.cms.hhs.gov/ColorectalCancerScreening
on May 8, 2009.
Frazier AL, Colditz GA, Fuchs CS, and Kuntz KM.
Cost-effectiveness of screening for colorectal cancer in the general
population. JAMA.
2000;284:1954-1961.
Hendriks YM, deJong AE, Morreau H, et al. Diagnostic approach
and management of Lynch syndrome (hereditary nonpolyposis colorectal
carcinoma): A guide for clinicians.
CA Cancer J Clin. 2006;56:213-225.
Levin B, Lieberman DA, McFarland, et al. Screening and
surveillance for the early detection of colorectal cancer and
adenomatous polyps, 2008: a joint guideline from the American Cancer
Society, the US Multi-Society Task Force on Colorectal Cancer, and the
American College of Radiology.
CA Cancer J Clin. 2008;58:130-160.
Rex DK, Kaho CJ, Levin B, et al. Guidelines for colonoscopy
surveillance after cancer resection: a consensus update by the American
Cancer Society and US Multi-Society Task Force on Colorectal Cancer. CA
Cancer J Clin. 2006;56:160-167.
Schrag D. The price tag on progress--chemotherapy for
colorectal cancer. N
Engl J Med. 2004;351:317-319.
Winawer, SJ, Zauber AG, Fletcher RH, et al. Guidelines for
colonoscopy surveillance after polypectomy: a consensus update by the
US Multi-Society Task Force on Colorectal Cancer and the American
Cancer Society. CA
Cancer J Clin. 2006;56:143-159.
Last Medical Review: 05/18/2009
Last Revised: 05/18/2009
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