Colorectal Cancer

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Colorectal Cancer

Topic Overview

Is this topic for you?

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.

What is colorectal cancer?

Colorectal cancer happens when cells that are not normal grow in your colon or rectum. These cells grow together and form tumours.

This cancer is also called colon cancer or rectal cancer. It is the third most common cancer in Canada and the United States. And it occurs most often in people older than 50.

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 experts, if everyone were tested, the number of deaths from colorectal cancer could be significantly reduced.

What causes colorectal cancer?

Most cases begin as polyps, which are small growths inside the colon or rectum. Colon polyps are very common, and most of them do not turn into cancer. But doctors cannot tell ahead of time which polyps will turn into cancer. This is why people older than 50 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.

What are the symptoms?

Colorectal cancer usually does not cause symptoms until after it has begun to spread. See your doctor if you have any of these symptoms:

  • Pain in your belly
  • Blood in your stool or very dark stools
  • A change in your bowel habits, such as more frequent stools or a feeling that your bowels are not emptying completely

How is colorectal cancer diagnosed?

If your doctor thinks that you may have this cancer, you will need a test, called a colonoscopy, 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, is used to diagnose colorectal cancer.

How is it treated?

Surgery is almost always used to treat colon and rectal cancer. The cancer is more easily removed when it is found early.

If the cancer has spread into the wall of the colon or farther, you may also need radiation or chemotherapy. These treatments have side effects, but most people can manage the side effects with medicines or home care.

When you first find out that you have cancer, you may have many feelings. You may feel scared or angry. Or you may feel very calm. There is no “right” way to react. It is normal to have a wide range of feelings. And it is normal for those feelings to change quickly.

Some people find that it helps to talk about their feelings with family and friends. You may also want to talk with your doctor or with other people who have had cancer. Your local Canadian Cancer Society chapter can help you find a support group.

How can you screen for colorectal cancer?

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. People who have a higher risk, such as people of African descent and people with a strong family history of colon cancer, should be tested sooner. Talk to your doctor about when you should be tested.

These are the most common screening tests:

  • Stool tests that check for signs of cancer:
    • Fecal occult blood test (FOBT)
    • Fecal immunochemical test (FIT)
  • Sigmoidoscopy (say "sig-moy-DAW-skuh-pee"). A doctor puts a flexible viewing tube into your rectum and into the first part of your colon. This lets the doctor see the lower portion of the intestine, which is where most colon cancers grow. Doctors can remove polyps during this test also.
  • Colonoscopy (say "koh-luh-NAW-skuh-pee"). A doctor puts a long, flexible viewing tube into your rectum and colon. The tube is usually linked to a video monitor similar to a TV screen. With this test, the doctor can see the entire large intestine.

The following tests may also be used to screen for colorectal cancer:

  • 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.
  • Barium enema. For this test, a liquid with barium is put into your rectum and colon. The white liquid outlines the inside of the colon so that it can be more clearly seen on an X-ray.

Frequently Asked Questions

Learning about colorectal cancer:

Being diagnosed:

Getting treatment:

Ongoing concerns:

Living with colorectal cancer:

Health Tools Health Tools help you make wise health decisions or take action to improve your health.

Health Tools help you make wise health decisions or take action to improve your health.


Decision Points focus on key medical care decisions that are important to many health problems. Decision Points focus on key medical care decisions that are important to many health problems.
  Colon Cancer: Which Screening Test Should I Have?

Actionsets help people take an active role in managing a health condition. Actionsets are designed to help people take an active role in managing a health condition.
  Bowel Disease: Caring for Your Ostomy
  Cancer: Controlling nausea and vomiting from chemotherapy
  Fitness: Adding More Activity to Your Life

Cause

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. Very few of them turn into cancer. If they are found early, usually through routine screening tests, they can be removed before they turn into cancer.

Symptoms

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:

  • Pain in the belly.
  • Blood in your stool or very dark stools.
  • A change in your bowel habits (such as more frequent stools or a feeling that your bowels are not emptying completely).
  • Constant tiredness (fatigue).
  • In rare cases, unexplained weight loss.

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.

  • The cecum and ascending colon, the first and second parts of the colon, are on the right side of your abdomen. Cancer in this area may bleed, causing blood in the stool and symptoms of anemia, including fatigue and weakness. The amount of blood may be small and so well mixed with stool that your stool may look normal. Sometimes cancer in this area does not cause many symptoms.
  • The transverse colon, the third part, goes across your body from right to left. Cancer here may cause abdominal cramps.
  • The descending colon, the fourth part, and the S-shaped sigmoid colon, the fifth part, are on the left side of your abdomen and join the rectum. Cancer here may cause narrower stools and bright red blood in the stool. Sometimes this blood is mistakenly thought to come from hemorrhoids.

Having these symptoms does not mean you have cancer. A number of other medical problems could cause similar symptoms, including:

What Happens

Cancer is the growth of abnormal cells in the body. These extra cells grow together and form masses, called tumours. In colorectal cancer, these growths usually start as polyps in the large intestine (colon or rectum). Colon polyps are quite common and most do not cause problems. But if they are not detected and removed, some of them can turn into cancer.

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

  • 90% or more if cancer is found early and treated before it has spread. This means that 90 or more out of 100 people will still be alive in 5 years if the cancer is found early and treated before it has spread.
  • 68% if the cancer has spread to nearby organs and lymph nodes. This means that 68 out of 100 people will still be alive in 5 years if the cancer has spread to nearby organs and lymph nodes.
  • 11% if the cancer has spread to the liver, lungs, or bones. This means that 11 out of 100 people will still be alive in 5 years if the cancer has spread to the liver, lungs, or other organs in the body.

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.

What Increases Your Risk

Colorectal cancer occurrence rates are highest among people of African descent. Rates are slightly lower among whites and lowest for Asians, Pacific Islanders, First Nations, and Hispanics.1

A risk factor is anything that increases your chance of getting a disease such as cancer. Risk factors for getting colorectal cancer include:

Your age

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 50.

Your family's medical history

You 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 are true:

  • You have at least three relatives who have had colon cancer, and at least one of them is a parent, brother, or sister.
  • Those relatives are spread over two generations in a row (for example, a grandparent and a parent).
  • One of those relatives had cancer before age 50.

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 non-polyposis colon cancer (HNPCC). Many people with these changed genes will develop colorectal cancer if they are not carefully watched. Genetic testing can tell you whether you carry a changed, or mutated, gene that can cause FAP or HNPCC.

Most people who get colorectal cancer do not have a personal or family history of the disease.

Your medical history

Your chances of getting colorectal cancer are higher if you have had:

Lifestyle changes to reduce your risk

When To Call a Doctor

Call your doctor if you have any symptoms of colorectal cancer, such as:

  • A change in bowel habits.
  • Bleeding from your rectum, including bright red or dark blood in your stools or stools that look black.
  • Constant or frequent diarrhea, constipation, or a feeling that your bowel doesn't empty completely.
  • Stools that are narrow (may be as narrow as a pencil).
  • Abdominal (belly) pain or problems with gas or bloating.
  • Unexplained weight loss.
  • Constant tiredness (fatigue).

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.

Watchful Waiting

Watchful waiting refers to a period of time in which your doctor is checking you regularly but not treating you. It is also called observation or surveillance. Watchful waiting is not a reasonable option when you have symptoms of colorectal cancer.

Who To See

Your family doctor or general practitioner can check your symptoms of colorectal cancer. You may be referred to a specialist, such as a gastroenterologist.

If your doctor thinks you may have colorectal cancer, he or she may refer you to see a general surgeon or a colon and rectal surgeon. Colorectal cancer is treated by surgeons, medical oncologists, and radiation oncologists.

To prepare for your appointment, see the topic Making the Most of Your Appointment.

Examinations and Tests

If your doctor thinks you may have colorectal cancer, he or she will ask you questions about your medical history and give you a physical examination. Other tests may include:

  • A colonoscopy, a test in which your doctor uses a lighted scope to view the inside of your entire colon. A colonoscopy may be done to look into symptoms such as unexplained bleeding from the rectum, constant diarrhea or constipation, blood in the stool, or pain in the lower abdomen. A colonoscopy is recommended when another screening test shows you may have colorectal cancer.2
  • A sigmoidoscopy, a test in which your doctor uses a lighted scope to view the lower part of your intestine. A sigmoidoscopy may be done to look into symptoms such as unexplained bleeding from the rectum, constant diarrhea or constipation, blood in the stool, or pain in the lower abdomen. Doctors can also remove polyps during this test.
  • A barium enema, in which a whitish liquid with barium is inserted through your rectum into your intestine. The barium outlines the inside of the colon so that it can be seen on an X-ray.
  • A biopsy, in which a sample of tissue is taken from the inside of your intestine and examined under a microscope. A doctor called a pathologist can look at the tissue sample and see if it contains cancer.
  • A complete blood count, which is a blood test. It is used to look into symptoms such as fatigue, weakness, anemia, bruising, or weight loss.

For people who have an increased risk for colorectal cancer, regular colonoscopy is the recommended screening test because 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:

Early Detection

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. See the What Increases Your Risk section of this topic for more information.

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.

The most common screening methods include:

Other tests, such as computed tomographic colonography (CTC, also known as virtual colonoscopy) and barium enema, may also be used to screen for colorectal cancer.

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 people of African descent 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 counsellor 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.

Click here to view a Decision Point. Colon Cancer: Which Screening Test Should I Have?

Treatment Overview

The first step in treating colorectal cancer is usually an operation to remove the tumour. 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 surgery.

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 should be.

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 radiation therapy, chemotherapy, or both.

Initial treatment

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:

  • Local incision. When the cancer is still just in a polyp, it will be removed during colonoscopy or sigmoidoscopy.
  • Resection. If your cancer is larger, your doctor will remove the cancer and a small amount of healthy tissue. The healthy ends of the colon or rectum are then sewn back together. During this operation, your doctor will also remove some of your lymph nodes for testing.
  • Resection and colostomy. Sometimes it isn't possible to rejoin the ends of the colon or rectum after the cancer is removed. Your doctor will do a colostomy and make an opening on the outside of your abdomen where waste can pass through into a colostomy bag. The colostomy may be temporary until your colon heals. Or it may be permanent if the entire lower colon or rectum was removed.

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 and to have this surgery at a hospital where many of these surgeries are done.3

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).

Chemotherapy uses 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.4

Side effects of treatment

The side effects of treatment for colorectal cancer will depend on the type of treatment you have and your age and overall health. The side effects of surgery, chemotherapy, or radiation may be mild enough that you can do things at home to manage them. See the Home Treatment section of this topic for more information.

Some of the treatment side effects can be avoided. For example, your doctor may prescribe medicines to control nausea and vomiting caused by chemotherapy. Other problems may be more serious, such as pain or tingling in your hands or feet that gets worse (peripheral neuropathy). These problems may be a sign that your medicines need to be changed. Be sure to talk to your doctor about all the side effects that you have.

For more information about specific treatments, see the following topics:

Ongoing treatment

After your treatment, you will need regular checkups by a family doctor, general practitioner, medical oncologist, radiation oncologist, or surgeon, depending on your case. During your follow-up visits you may have one or more of these tests:

  • Physical examinations. How often you have these depends on your general health and the type of colorectal cancer you have. In general, you will see your doctor several times a year for 3 to 5 years and then return to once-a-year checkups.
  • Colonoscopy, to inspect the inner surface of your colon and rectum for new problems
  • Carcinoembryonic antigen (CEA) and other blood tests, to check the success of your treatment and find out whether the cancer has returned
  • CT scan or MRI, to see if the cancer has spread to other organs

Treatment if the condition gets worse

Colorectal cancer comes back after surgery in about half of people who have surgery to remove the cancer.4 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. A cure is less likely, but treatment can help you feel better and live longer. For more information, see the topic Colorectal Cancer, Metastatic and Recurrent.

What To Think About

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.

Prevention

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. People with a higher risk, such as people of African descent and people with a strong family history of colon cancer, should be tested sooner. 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 experts, if everyone were tested, the number of deaths from colorectal cancer could be significantly reduced.

The following guidelines are for people who do not have an increased risk for colorectal cancer.5, 6

Colorectal cancer screening guidelines for people 50 and older at average risk
Test Frequency

Stool test,* such as the fecal occult blood test (FOBT) or fecal immunochemical test (FIT)

Every 1 to 2 years

or

Sigmoidoscopy*

Every 10 years

or

Colonoscopy

Every 10 years

*Some experts recommend combining a stool test with a sigmoidoscopy.

Other tests that may be used to screen for colorectal cancer include:

Some people may need to begin routine testing earlier than age 50 and have it done more often. You may need earlier or more frequent testing if you have a higher risk for colon cancer.

Virtual colonoscopy (also called computed tomographic colonography, or CTC) uses X-rays and a computer to take pictures of the inside of your large intestine. It may be used as a screening test for people who do not have an increased risk for colon cancer or for people who cannot have a colonoscopy.

Click here to view a Decision Point. Colon Cancer: Which Screening Test Should I Have?

Here are other things you can do to help prevent colorectal cancer:

  • Watch your weight. Being very overweight may increase your risk. And carrying extra fat around the waist seems to be more of a risk than carrying extra fat in the hips or thighs.
  • Eat well. Healthy eating includes a variety of foods. Eat more whole grains, fruits, vegetables, poultry, and fish. And eat less red meat, refined grains, and sweets.
  • Limit drinking. Drink less than 2 alcohol drinks a day. People who drink 2 or more alcohol drinks a day have a slightly higher risk for colorectal cancer.1
  • Get active. Keep up a physically active lifestyle. Being fit leads to an improved sense of well-being, improved appearance, and increased stamina and strength.
  • Quit smoking. If you smoke cigarettes, quit smoking to reduce your risk.

What to think about

If you have a very strong family history of colon cancer, you may want to talk to your doctor or a genetic counsellor 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 have at least three relatives who have had colon cancer, and at least one of them is a parent, brother, or sister.
  • Those relatives are spread over two generations in a row (for example, a parent and a grandparent).
  • One of those relatives had cancer before age 50.

Home Treatment

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 symptoms.

  • Home treatment for nausea or vomiting includes watching for and treating early signs of dehydration, such as a dry mouth, sticky saliva, having smaller than usual amounts of urine, or having urine that is dark yellow. Your doctor may also prescribe medicines to help control nausea and vomiting. For more information on how to deal with these side effects, see:
    Click here to view an Actionset. Cancer: Controlling Nausea and Vomiting From Chemotherapy.
  • Home treatment for diarrhea includes resting your stomach by not eating for several hours or until you feel better and watching for signs of dehydration. Check with your doctor before using any drugs for your diarrhea.
  • Home treatment for constipation includes gentle exercise, drinking plenty of fluids, and eating lots of fruits, vegetables, and foods that contain fibre. Check with your doctor before using a laxative.
  • Home treatment for fatigue includes getting extra rest while you are having chemotherapy or radiation therapy. Let your symptoms be your guide. You may be able to stick to your usual routine and just get some extra sleep. Fatigue is often worse at the end of treatment or just after treatment is completed.
  • Home treatment for sleep problems includes going to bed at the same time every night, exercising during the day, and avoiding caffeine late in the day.
  • Home treatment for pain can range from hot packs or cold packs to relaxation or aromatherapy and can improve your physical and mental well-being. Not all forms of cancer and cancer treatment cause pain. Talk to your doctor before using any home treatment for pain.
  • Home treatment for mouth sores can reduce your discomfort:
    • Drink cold liquids, such as water or iced tea, or eat flavoured ice treats or frozen juices.
    • Eat foods that are easy to swallow, such as gelatin, ice cream, or custard.
    • Drink from a straw.
    • Rinse your mouth several times a day with a warm saltwater rinse. Mix 1 tsp (5 g) of salt with 1 cup (0.2 L) of warm water.

Managing stress

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.

Consider meeting with a counsellor 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 about your worries with your partner and discussing your feelings with a doctor.

For more information about learning how to live with cancer, read "Taking Time: Support for People With Cancer" from the U.S. National Cancer Institute. This booklet is available online at www.cancer.gov/cancertopics/takingtime.

Medications

Chemotherapy is the use of drugs to control the cancer's growth or relieve symptoms. Often the drugs are given through a needle in your vein, and your blood vessels carry the drugs through your body. Sometimes the drugs are available as pills you can swallow. Sometimes they are given through a shot, or injection.

Several drugs are used to treat colorectal cancer. There are also several drugs available for treating side effects.

Medication Choices

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.

Treating the side effects

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 may include:

  • Serotonin antagonists, such as ondansetron (Zofran), granisetron (Kytril), or dolasetron (Anzemet). These drugs more effectively prevent nausea and vomiting caused by chemotherapy when they are combined with corticosteroids, such as dexamethasone.
  • Aprepitant (Emend), which is used in combination with ondansetron and dexamethasone as part of a 3-day program.
  • Antiemetics, such as promethazine and prochlorperazine.
  • Metoclopramide.

There also are things you can do at home to manage side effects. See the Home Treatment section for more information.

What To Think About

Chemotherapy and 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

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. For more information, see the Home Treatment section of this topic.

Surgery Choices

  • Local excision. When colorectal cancer is discovered in its very early stages, it can be removed during a sigmoidoscopy or colonoscopy. The surgeon cuts out not just the polyp, but also a small amount of tissue around it. The surgeon does not need to cut into the abdomen.
  • Bowel resection. This operation involves cutting out the cancer as well as the sections of the colon or rectum that are next to it. Then the two healthy ends of the colon or rectum are sewn back together. The surgery can be done in two ways:
    • Open resection. The surgeon makes a long incision in the abdomen, completes the bowel resection, and closes the incision.
    • Laparoscopic surgery. This is done with several small incisions in the belly for a tiny camera and special instruments. But laparoscopic surgery cannot always be done, such as when the cancer has spread to areas outside the colon.

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.

What To Think About

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 colostomy.

For more information, see:

Click here to view an Actionset. Bowel Disease: Caring for Your Ostomy.

Other Treatment

Radiation therapy uses X-rays to destroy colorectal cancer cells and shrink tumours. 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 chemotherapy.

Other Treatment Choices

Radiation may be given:

  • Externally, using a machine outside the body that points a beam of radiation at the tumour.
  • Internally, by placing tiny radioactive "seeds" next to or into the cancer.

Compared to surgery alone, radiation given before surgery may reduce the risk that rectal cancer will return and may help you live longer.4

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.

What To Think About

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.

Other Places To Get Help

Organizations

Canadian Cancer Society
10 Alcorn Avenue
Suite 200
Toronto, ON  M4V 3B1
Phone: (416) 961-7223
Fax: (416) 961-4189
Email: ccs@cancer.ca
Web Address: http://cancer.ca
 

The Canadian Cancer Society (CCS) is a national, community-based organization that provides information about cancer prevention, care, and treatment. The CCS also provides funding for cancer research.


Canadian Digestive Health Foundation
Web Address: www.cdhf.ca
 

The Canadian Digestive Health Foundation provides educational information about digestive diseases and supports research into their causes and treatment.


Cancer.Net
Phone: 1-888-651-3038
(571) 483-1300
Fax: (571) 366-9537
Email: contactus@cancer.net
Web Address: www.cancer.net
 

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.


Colorectal Cancer Association of Canada
Web Address: www.colorectal-cancer.ca
 

The Colorectal Cancer Association of Canada (CCAC) provides resources and support to people with colorectal cancer, their families, and caregivers. The CCAC also educates the general public about colorectal cancer.


U.S. National Cancer Institute (NCI)
6116 Executive Boulevard
Suite 300
Bethesda, MD  20892-8322
Phone: 1-800-4-CANCER (1-800-422-6237)
Web Address: www.cancer.gov (or https://cissecure.nci.nih.gov/livehelp/welcome.asp# for live help online)
 

The U.S. 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.


United Ostomy Association of Canada
P.O. Box 825-50 Charles Street East
Toronto, ON  M4Y 2N7
Phone: (416) 595-5452
1-888-969-9698
Fax: (416) 595-9924
Email: info@ostomycanada.ca
Web Address: www.ostomycanada.ca

References

Citations

  1. American Cancer Society (2008). Colorectal Cancer Facts and Figures 2008–2010. Atlanta: American Cancer Society. Available online: http://www.cancer.org/docroot/STT/content/STT_1x_Colorectal_Cancer_Facts__Figures_2008-2010.asp.
  2. Winawer S, et al. (2003). Colorectal cancer screening and surveillance: Clinical guidelines and rationale—Update based on new evidence. Gastroenterology, 124(2): 544–560.
  3. National Comprehensive Cancer Network (2010). Colon cancer. NCCN Clinical Practice Guidelines in Oncology, version 2. Available online: http://www.nccn.org/professionals/physician_gls/f_guidelines.asp#site.
  4. Lewis C (2007). Colorectal cancer screening, search date November 2006. Online version of BMJ Clinical Evidence: http://www.clinicalevidence.com.
  5. Leddin D, et al. (2010). Canadian Association of Gastroenterology position statement on screening individuals at average risk for developing colorectal cancer: 2010. Canadian Journal of Gastroenterology, 24(12): 705–714.
  6. Leddin D, et al. (2004). Canadian Association of Gastroenterology and the Canadian Digestive Health Foundation: Guidelines on colon cancer screening. Canadian Journal of Gastroenterology, 18(2): 93–99.

Other Works Consulted

  • American Cancer Society (2008). Cancer Facts and Figures 2008. Atlanta: American Cancer Society. Available online: http://www.cancer.org/docroot/STT/content/STT_1x_Cancer_Facts_and_Figures_2008.asp.
  • American Cancer Society (2009). Cancer Facts and Figures 2009. Atlanta: American Cancer Society. Available online: http://www.cancer.org/acs/groups/content/@nho/documents/document/500809webpdf.pdf.
  • Basch EM, et al. (2008). Complementary, alternative, and integrative therapies. In VT DeVita Jr et al., eds., DeVita, Hellman, and Rosenberg’s Cancer: Principles and Practice of Oncology, 8th ed., vol. 2, pp. 2950–2963. Philadelphia: Lippincott Williams and Wilkins.
  • Blanchard EM, Hesketh PJ (2008). Nausea and vomiting section of Management of adverse effects of treatment. In VT DeVita Jr et al., eds., DeVita, Hellman, and Rosenberg’s Cancer: Principles and Practice of Oncology, 8th ed., vol. 2, pp. 2639–2646. Philadelphia: Lippincott Williams and Wilkins.
  • Canadian Cancer Society (2010). Colorectal cancer stats. Available online: http://www.cancer.ca/Canada-wide/About%20cancer/Cancer%20statistics/Stats%20at%20a%20glance/Colorectal%20cancer.aspx?sc_lang=en.
  • Canadian Cancer Society (2010). Colorectal cancer: Screening for colorectal cancer. Available online: http://www.cancer.ca/Canada-wide/Prevention/Getting%20checked/Colorectal%20cancer%20NEW.aspx?sc_lang=en.
  • Canadian Cancer Society and National Cancer Institute of Canada (2010). Canadian Cancer Statistics 2010. Toronto: Canadian Cancer Society. Available online: http://www.cancer.ca/canada-wide/about%20cancer/cancer%20statistics/canadian%20cancer%20statistics.aspx.
  • Cherry NI (2008). Diarrhea and constipation. In VT DeVita Jr et al., eds., DeVita, Hellman, and Rosenberg’s Cancer: Principles and Practice of Oncology, 8th ed., vol. 2, pp. 2646–2655. Philadelphia: Lippincott Williams and Wilkins.
  • Leddin D, et al. (2004). Canadian Association of Gastroenterology and the Canadian Digestive Health Foundation: Guidelines on colon cancer screening. Canadian Journal of Gastroenterology, 18(2): 93–99.
  • National Cancer Institute (2010). Genetics of Colorectal Cancer PDQ—Health Professional Version. Available online: http://www.cancer.gov/cancertopics/pdq/genetics/colorectal/healthprofessional.
  • National Comprehensive Cancer Network (2010). Rectal cancer. NCCN Clinical Practice Guidelines in Oncology, version 2. Available online: http://www.nccn.org/professionals/physician_gls/f_guidelines.asp#site.

Credits

By Healthwise Staff
Primary Medical Reviewer Kathleen Romito, MD - Family Medicine
Primary Medical Reviewer Andrew Swan, MD, CCFP, FCFP - Family Medicine
Specialist Medical Reviewer Arvydas D. Vanagunas, MD - Gastroenterology
Last Revised December 30, 2010

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