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This topic will tell you
about the initial testing, diagnosis, and treatment of colorectal
cancer. If you want to learn about colorectal cancer that has
come back or has spread, see the topic
Colorectal Cancer, Metastatic or Recurrent.
happens when cells that are not normal grow in your
colon or rectum. These cells grow together and form polyps. Over time, some polyps can turn into cancer.
cancer is also called colon cancer or rectal cancer, depending on where the cancer is. It is the third most
common cancer in the United States. And it occurs most often in people older
As with other cancers, treatment for colorectal cancer works best when the cancer is found early. Screening tests can detect or prevent this cancer, but only about half of people older
than 50 are screened. According to the American Cancer Society, if everyone
were tested, tens of thousands of lives could be saved each year.
Most cases begin as
polyps, which are small growths inside the colon or
Colon polyps are very common. Some polyps can turn into cancer. But doctors cannot tell ahead of time which polyps will turn
into cancer. This is why people age 50 and older need regular tests to find out if
they have any polyps and then have them removed. And some people who are
younger than 50 need regular tests if their medical history puts them at
increased risk for colorectal cancer.
Colorectal cancer usually
does not cause symptoms until after it has begun to spread. See your doctor if
you have any of these symptoms:
If your doctor
thinks that you may have this cancer, you will need a test, called a
colonoscopy (say "koh-luh-NAW-skuh-pee"), that lets the doctor see the inside of
your entire colon and rectum. During this test, your doctor will remove polyps
or take tissue samples from any areas that don't look normal. The tissue will
be looked at under a microscope to see if it contains cancer.
Sometimes another test, such as a
sigmoidoscopy (say "sig-moy-DAW-skuh-pee"), is used to diagnose colorectal
Colorectal cancer is usually treated with surgery, chemotherapy, or radiation.
Finding out that you have cancer can change your life. You may feel like your world has turned upside down and you have lost all control. Talking with family, friends, or a counselor can really help. Ask your doctor about support groups. Or call the American Cancer Society (1-800-227-2345) or visit its website at www.cancer.org.
Screening tests can find or prevent many cases of colon and rectal cancer. They
look for a certain disease or condition before any symptoms appear. Experts
recommend routine colon cancer testing for everyone age 50 and older who has a
normal risk for colon cancer. Your doctor may recommend earlier or more frequent testing if you have a higher risk for colorectal cancer. Talk to your doctor about when you should be tested.
These are the most common screening tests:
Learning about colorectal cancer:
Living with colorectal cancer:
Health Tools help you make wise health decisions or take action to improve your health.
The exact cause of
colorectal cancer is not known. Most cases begin as
small growths, or polyps, inside the colon or rectum.
Colon polyps are very common. If they are
found early, usually through routine screening tests, they can be removed
before they turn into cancer.
Colorectal cancer in its early stages usually doesn't
cause any symptoms. Symptoms occur later, when the cancer may be more difficult
to treat. The most common symptoms include:
Colon cancer may not cause symptoms you notice in the early stages. When there are
symptoms, they may depend on where the cancer is in your colon.
Having these symptoms does not mean you have cancer. A
number of other medical problems could cause similar symptoms,
Cancer is the growth of
abnormal cells in the body. These extra cells grow together and form masses,
called tumors. In
colorectal cancer, these growths usually start as
polyps in the
large intestine (colon or rectum).
Colon polyps are quite common. But if they are not detected and removed, the polyps may turn into
Cancers in the colon or rectum usually grow very slowly.
It takes most of them years to become large enough to cause symptoms. If the
cancer is allowed to grow, it eventually will invade and destroy nearby tissues
and then spread farther. Colorectal cancer spreads first to nearby
lymph nodes. From there it may spread to other parts
of the body, usually the liver. It may also spread to the lungs, and less
often, to other organs in the body.
The long-term outcome, or
prognosis, for colorectal cancer depends on how much the cancer has grown and
spread. Experts talk about prognosis in terms of "5-year survival rates." The
5-year survival rate means the percentage of people who are still alive 5 years
or longer after their cancer was discovered. It is important to remember that
these are only averages. Everyone's case is different. And these numbers do not
necessarily show what will happen to you. The estimated 5-year survival rate
for colorectal cancer is:1
These numbers are taken from reports that were done at least 5 years ago, before newer treatments were available. So the actual chances of your survival are likely to be higher than these numbers.
A risk factor for colorectal cancer is something that increases your chance of getting this cancer. Having one or more of these risk factors can make it more likely that you will get colorectal cancer. But it doesn't mean that you will definitely get it. And many people who get colorectal cancer don't have any of these risk factors.
Everyone who is older than 50 has a risk
of getting colorectal cancer. And the older you are, the greater the risk. Most
cases of colorectal cancer are diagnosed in people older than 50. Most people
who get colorectal cancer have no other risk factors besides being older than
African Americans are at greater risk of getting colorectal cancer (and dying from it) than non-Hispanic whites. And non-Hispanic white people have a higher risk than other major racial or ethnic groups, such as Hispanics, Asians, and Pacific Islanders.2
Ashkenazi Jews (Jewish people whose ancestors came from Eastern Europe) who have inherited certain genes are also at a higher risk for getting colorectal cancer.3
are more likely to get colorectal cancer if one of your parents, brothers,
sisters, or children has had the disease. This is considered a strong family history. Your risk depends on how old your
family member was when he or she was diagnosed and on how many members of your
family have had the disease.
You have a very strong family history if all of the following
If you have a very strong family history of colorectal and related cancers, you may want to have genetic testing. Related cancers include ovarian cancer, stomach cancer, liver cancer, or cancer of the small bowel, among others. Genetic testing is done with a blood test that looks for changed genes (mutations).
The most common gene changes occur in two conditions:
familial adenomatous polyposis (FAP) and
Lynch syndrome, also called hereditary nonpolyposis colon cancer (HNPCC). Many
people with these changed genes will develop colorectal cancer if they are not
Genetic testing can tell you whether you carry a
changed, or mutated, gene that can cause FAP or HNPCC.
chances of getting colorectal cancer are higher if you have had:
Call your doctor if you have any
colorectal cancer, such as:
Because colorectal cancer often does not cause any
symptoms, talk with your doctor about
screening tests. Screening helps doctors find a
certain disease or condition before any symptoms appear. Some screening tests
for colorectal cancer can find and remove small precancerous growths in the
colon and rectum called
adenomatous polyps. If these are found and removed
early, they cannot turn into cancer.
Health professionals who can evaluate your symptoms of
colorectal cancer include:
If your doctor thinks you may have colorectal cancer, he
or she may advise you to see a
general surgeon or a
colorectal surgeon. Colorectal cancer is treated
medical oncologists, and
To prepare for your appointment, see the topic Making the Most of Your Appointment.
If your doctor thinks you may have
colorectal cancer, he or she will ask you questions
medical history and give you a physical exam. Other
tests may include:
For people who have an increased risk for colorectal
colonoscopy is the recommended screening test. It allows your doctor to remove polyps (polypectomy) and take tissue samples at
the same time.
When you are diagnosed with colorectal cancer,
your doctor may order other tests to find out whether the cancer has spread.
These tests include:
Colorectal cancer has a much better chance of being successfully treated when it is found early. Most people who get colorectal cancer
are older than 50 and have no other risk factors besides their age.
Routine screening can reduce deaths from colorectal cancer. Some screening tests find and remove polyps before they can turn into cancer. Other screening tests look for early signs of cancer, because that is when treatment works better. Screening methods include:
Stool tests look for signs of cancer. If used as recommended, these tests may find cancer early, when treatment works better. Sigmoidoscopy and colonoscopy are tests that find and remove polyps to stop them from turning into cancer. Virtual colonoscopy finds polyps. With stool tests and virtual colonoscopy, if there are abnormal findings, you will need to have a colonoscopy to remove any polyps.
Talk to your doctor about which test is right for you.
People with a higher risk for colorectal cancer, such as African Americans and
people with a strong family history of colon cancer, may need to begin routine
testing before age 50 and have it more often.
If you have a very
strong family history of colon cancer, you may want to talk to your doctor or a
genetic counselor about having a blood test to look
for changed genes.
Genetic testing can tell you whether you carry a
changed, or mutated, gene that can cause colon cancer. Having certain genes
greatly increases your risk of colon cancer. But most cases of colon cancer are
not caused by changed genes.
The first step in treating
colorectal cancer is usually an operation to remove
the tumor. Sometimes a simple operation can be done during a colonoscopy or
sigmoidoscopy to remove small polyps and a small amount of tissue surrounding
them. But in most cases a major operation, in which the cancer and part of the
colon or rectum around it are removed, is needed. If cancer has spread to
another part of your body, such as the liver, you may need more far-reaching
After the cancer has been examined under a microscope, it
will be staged. Staging is a way for your doctor to tell how far, if at all,
your cancer has spread. It also helps your doctor decide what your treatment
There are several different types of
staging systems, so it's important to ask your doctor
to explain carefully what stage your cancer is in and what that means.
Cancers that have not spread beyond the colon or rectum may
require only surgery. If the cancer has spread, you may need
chemotherapy, or both.
You and your doctor will work
together to decide what your treatment should be. You will consider your own
preferences and your general health, but the
stage of your cancer is the most important tool for
choosing your treatment.
Surgery is almost
always used to remove
colorectal cancer. Your doctor may use one of the following types of surgery:
Sometimes it is possible to have laparoscopic surgery to remove the cancer. This is surgery where very small incisions are made in the belly. A tiny camera and special instruments are used to remove the cancer. For the best results, it is important to have an experienced surgeon.5
Even after removing all the cancer that can be found with surgery, your doctor may say you need other treatment. This may be chemotherapy, radiation, or both (chemoradiation).
medicines—given either as pills or through a needle—to destroy cancer cells
throughout the body. Several medicines are often used together. Research studies continue to look for the best combinations of medicines. Your doctor will recommend treatment based on the type and stage of cancer that you have.
Radiation therapy, which uses X-rays to destroy cancer cells,
is standard treatment for some types of cancer in the rectum. Radiation therapy
is often combined with surgery or chemotherapy. Radiation may be given from a machine outside the body that targets the cancer (external radiation). Or it may be given inside the body, with radiation sealed in seeds or wires (internal radiation).
Compared to surgery alone,
radiation therapy given before surgery for rectal cancer may reduce the risk
that the cancer will return and may help you live longer.6
Surgery, chemotherapy, or radiation can have serious side effects. But your medical team will help you manage the side effects of your treatment. This may include medicines for pain following surgery or medicines to control nausea and vomiting if you have chemotherapy.
Talk with your doctor and medical team about your side effects. Some side effects, such as pain or tingling in your hands or feet that gets worse (peripheral neuropathy), may be a sign that your medicines need to be changed.
For tips on how to manage side effects at home, see the Home Treatment section of this topic.
Additional information about colon and rectal cancer is provided by the National Cancer Institute at www.cancer.gov/cancertopics/types/colon-and-rectal.
After your treatment, you will
need regular checkups by a
radiation oncologist, or
surgeon, depending on your case. During your follow-up
visits you may have one or more of these tests:
Colorectal cancer comes back after surgery in about half of people who have surgery
to remove the cancer.6 The cancer may be more likely
to come back after surgery if it was not discovered in an early stage. Cancer that has spread or comes back is harder to treat, but sometimes treatments are successful. For more information, see
Colorectal Cancer, Metastatic and Recurrent.
After you have had colorectal
cancer, your chances of having it again go up. It's important to continue to
see your doctor and be tested regularly to help find any returning cancer or
new polyps early.
Clinical trials are designed to find
better ways to treat people with cancer and are based on the most current
information. Some people who meet the criteria for participation choose to
enroll in such clinical trials.
Some tests can prevent
colorectal cancer. Screening tests look for a certain
disease or condition before any symptoms appear. Experts recommend routine
colon cancer testing for everyone age 50 and older who has a normal risk for
colon cancer. Your doctor may recommend earlier or more frequent testing if you have a higher risk for colon cancer. Talk to
your doctor about when you should be tested.
Fewer than half of
people who are older than 50 are screened for colorectal cancer. According to
the American Cancer Society, if everyone were tested, tens of thousands of
lives could be saved each year.
The following guidelines are for
people who do not have an increased risk for colorectal
test,* such as the
fecal occult blood test (FOBT), fecal
immunochemical test (FIT), or stool DNA test (sDNA)
Every year for the FOBT and FIT
Every 5 years for sDNA
Computed tomographic colonography (CTC), also called a virtual colonoscopy
combining a stool test with a sigmoidoscopy.
For more information, see:
Here are other things you can do to help prevent colorectal
If you have a
very strong family history of colon cancer, you may want to talk to your doctor or a
genetic counselor about having a blood test to look for changed genes.
Genetic testing can tell you whether you carry a
changed, or mutated, gene that can cause colon cancer. Having certain genes
greatly increases your risk of colon cancer.
You have a very strong
family history if each of the following is true:
You can do things at home to help manage
the side effects of
colorectal cancer or its treatment. Be sure to follow
your doctor's advice on any drugs you are taking. Healthy habits such as eating
a balanced diet and getting enough sleep and exercise may help control your
Learning that you have colorectal cancer and being treated for it can be
very stressful. There are steps you can take to reduce your stress. You may want to talk with family or friends. Some people find that spending time alone is what they need.
meeting with a counselor or joining a support group of others who have
colorectal cancer. Your doctor may also be able to help you find other sources
of support and information. Learning relaxation techniques, such as yoga or
visualization exercises, may also help you reduce your stress.
Your feelings about your body may change after treatment.
Dealing with your body image may involve talking
openly with your partner about your worries and discussing your feelings with a
Having cancer can change your life in many ways. For help with managing these changes, see the topic Getting Support When You Have Cancer.
For more information about learning how to live with cancer, read "Taking Time: Support for People With Cancer" from the National Cancer Institute. This booklet is available online at www.cancer.gov/cancertopics/takingtime.
Chemotherapy is the use of medicines to control
the cancer's growth or relieve symptoms. Often the medicines are given through a
needle in your vein, and your blood vessels carry the medicines through your body.
Sometimes the medicines are available as pills you can swallow. Sometimes they are
given as a shot, or injection.
Several medicines are used to
colorectal cancer. There are also several medicines
available for treating side effects.
A combination of drugs often works better than a single
drug in treating colorectal cancer. The most commonly used drugs are:
Hair loss, a side effect common with some types of
chemotherapy, is usually not a side effect of these drugs.
Your doctor may
prescribe medicines that can help relieve side effects of chemotherapy. These
side effects can include mouth sores, diarrhea, nausea, and vomiting. Your
doctor may prescribe
medicines to control nausea and vomiting. These drugs
There also are things you can do at home to manage side
effects. See Home Treatment for more information.
radiation may be combined to treat some types of
colorectal cancer. Radiation or chemotherapy given before or after surgery can
destroy microscopic areas of cancer to increase the chances of a cure.
Surgery to remove cancer is almost always the
main treatment for
colorectal cancer. The type of surgery depends on the
size and location of your cancer.
Side effects are common after
surgery. You may be able to reduce the severity of your side effects at home.
See Home Treatment for more information.
Your doctor may suggest radiation therapy or chemotherapy if he or she thinks the cancer may come back (recur). If the cancer has spread to nearby lymph nodes, you may need chemotherapy after your surgery. Or if your surgery shows that the cancer has spread outside your colon or rectum, you may need radiation therapy.
Polypectomy or local excision is
used when the cancer has been caught in its early stages. Bowel resection is
used when the cancer is larger. Sometimes after this major operation, the two
ends of the colon or rectum cannot be sewn back together. When this happens, a
colostomy is performed. Most people do not need a
Radiation therapy uses X-rays to destroy
colorectal cancer cells and shrink tumors. It is often
used to treat rectal cancer, usually combined with surgery. It is used less
often to treat colon cancer. It may also be combined with
Radiation may be given:
Compared to surgery alone, radiation given before surgery
may reduce the risk that rectal cancer will return and may help you live
People sometimes use complementary therapies along with medical treatment to help relieve symptoms and side effects of cancer treatments. Some of the complementary therapies that may be helpful include:
Mind-body treatments like the ones listed above may help you feel better. They can make it easier to cope with cancer treatments. They also may reduce chronic low back pain, joint pain, headaches, and pain from treatments.
Before you try a complementary therapy, talk to your doctor about the possible value and potential side effects. Let your doctor know if you are already using any such therapies. Complementary therapies are not meant to take the place of standard medical treatment, but they may improve your quality of life and help you deal with the stress and side effects of cancer treatment.
You may be interested in taking part in research studies called clinical trials. Clinical trials are based on the most up-to-date information and are designed to find better ways to treat people who have cancer. People who do not want standard treatments or are not cured by standard treatments may want to take part in clinical trials. These are ongoing in most parts of the United States and in some other countries around the world for all stages of colorectal cancer.
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 number have information about services and activities
in local areas and can provide referrals to local ACS divisions.
The American College of Gastroenterology is an organization of digestive disease specialists. The website contains information about common gastrointestinal problems.
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.
Cancer.Net is the information website of the American
Society of Clinical Oncology (ASCO) for people living with cancer and for those
who care for them. ASCO is the world's leading professional organization
representing physicians of all oncology subspecialties. Cancer.Net provides
current oncologist-approved information on living with cancer.
The National Cancer Institute (NCI) is a U.S. government
agency that provides up-to-date information about the prevention, detection,
and treatment of cancer. NCI also offers supportive care to people who have cancer
and to their families. NCI information is also available to doctors, nurses,
and other health professionals. NCI provides the latest information about
clinical trials. The Cancer Information Service, a service of NCI, has trained
staff members available to answer questions and send free publications.
Spanish-speaking staff members are also available.
The U.S. National Institutes of Health (NIH) conducts
and supports medical research to improve people's health and save lives. NIH
provides access to health and wellness information, free newsletters, current
research, health databases, fact sheets, and many other resources.
American Cancer Society (2012). Cancer Facts and Figures 2012. Atlanta: American Cancer Society. Available online: http://www.cancer.org/Research/CancerFactsFigures/CancerFactsFigures/cancer-facts-figures-2012.
American Cancer Society (2011). Colorectal Cancer Facts and Figures 2011–2013. Atlanta: American Cancer Society. Available online: http://www.cancer.org/Research/CancerFactsFigures/ColorectalCancerFactsFigures/colorectal-cancer-facts-figures-2011-2013-page.
Libutti SK, et al. (2011). Cancer of the colon. In VT DeVita Jr. et al., eds., DeVita, Hellman and Rosenberg's Cancer: Principles and Practice of Oncology, 9th ed., pp. 1084–1126. Philadelphia: Lippincott Williams and Wilkins.
Winawer S, et al. (2003).
Colorectal cancer screening and surveillance: Clinical guidelines and
rationale—Update based on new evidence. Gastroenterology, 124(2): 544–560.
National Comprehensive Cancer Network (2012). Colon cancer. NCCN Clinical Practice Guidelines in Oncology, version 3. Available online: http://www.nccn.org/professionals/physician_gls/f_guidelines.asp#site.
Lewis C (2007). Colorectal cancer screening, search
date November 2006. Online version of BMJ Clinical Evidence:
Other Works Consulted
Cherny NJ (2011). Diarrhea and constipation. In VT DeVita Jr. et al., eds., DeVita, Hellman and Rosenberg's Cancer: Principles and Practice of Oncology, 9th ed., pp. 2329–2336. Philadelphia: Lippincott Williams and Wilkins.
National Cancer Institute (2010). Colon Cancer PDQ: Treatment—Health Professional Version. Available online: http://www.cancer.gov/cancertopics/pdq/treatment/colon/HealthProfessional.
National Cancer Institute (2011). Colon Cancer PDQ: Treatment—Patient Version. Available online: http://www.cancer.gov/cancertopics/pdq/treatment/colon/Patient.
National Cancer Institute (2011). Rectal Cancer PDQ: Treatment—Health Professional Version. Available online: http://www.cancer.gov/cancertopics/pdq/treatment/rectal/HealthProfessional/allpages.
National Cancer Institute (2012). Genetics of Colorectal Cancer PDQ—Health Professional Version. Available online: http://www.cancer.gov/cancertopics/pdq/genetics/colorectal/healthprofessional/allpages.
National Cancer Institute (2012). Rectal Cancer Treatment (PDQ)—Patient Version. Available online: http://www.cancer.gov/cancertopics/pdq/treatment/rectal/Patient.
National Comprehensive Cancer Network (2012). Rectal cancer. NCCN Clinical Practice Guidelines in Oncology, version 3. Available online: http://www.nccn.org/professionals/physician_gls/f_guidelines.asp#site.
October 22, 2012
E. Gregory Thompson, MD - Internal Medicine & Kenneth Bark, MD - Surgery, Colon and Rectal
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