Filed under: Cancer & Chemo
Colon cancer is cancer of the large intestine (colon), the lower part of
your digestive system. Rectal cancer is cancer of the last several
inches of the colon. Together, they're often referred to as colorectal
Most cases of colon cancer begin as small, noncancerous (benign) clumps
of cells called adenomatous polyps. Over time some of these polyps
become colon cancers.
Polyps may be small and produce few, if any, symptoms. For this reason,
doctors recommend regular screening tests to help prevent colon cancer
by identifying polyps before they become colon cancer.
Signs and symptoms of colon cancer include:
* A change in your bowel habits, including diarrhea or constipation
or a change in the consistency of your stool for more than a couple of
* Rectal bleeding or blood in your stool
* Persistent abdominal discomfort, such as cramps, gas or pain
* A feeling that your bowel doesn't empty completely
* Weakness or fatigue
* Unexplained weight loss
Many people with colon cancer experience no symptoms in the early stages
of the disease. When symptoms appear, they'll likely vary, depending on
the cancer's size and location in your large intestine.
When to see a doctor
If you notice any symptoms of colon cancer, such as blood in your stool
or a persistent change in bowel habits, make an appointment with your
Talk to your doctor about when you should begin screening for colon
cancer. Guidelines generally recommend colon cancer screenings begin at
age 50. Your doctor may recommend more frequent or earlier screening if
you have other risk factors, such as a family history of the disease.
It's not clear what causes colon cancer in most cases. Doctors know that
colon cancer occurs when healthy cells in the colon become altered.
Healthy cells grow and divide in an orderly way to keep your body
functioning normally. But sometimes this growth gets out of control —
cells continue dividing even when new cells aren't needed. In the colon
and rectum, this exaggerated growth may cause precancerous cells to form
in the lining of your intestine. Over a long period of time — spanning
up to several years — some of these areas of abnormal cells may become
Precancerous growths in the colon
Colon cancer most often begins as clumps of precancerous cells (polyps)
on the inside lining of the colon. Polyps can appear mushroom-shaped.
Precancerous growths can also be flat or recessed into the wall of the
colon (nonpolypoid lesions). Nonpolypoid lesions are more difficult to
detect, but are less common. Removing polyps and nonpolypoid lesions
before they become cancerous can prevent colon cancer.
Inherited gene mutations that increase the risk of colon cancer
Inherited gene mutations that increase the risk of colon cancer can be
passed through families, but these inherited genes are linked to only a
small percentage of colon cancers. Inherited gene mutations don't make
cancer inevitable, but they can increase an individual's risk of cancer
significantly. Inherited colon cancer syndromes include:
* Familial adenomatous polyposis (FAP). FAP is a rare disorder that
causes you to develop thousands of polyps in the lining of your colon
and rectum. People with untreated FAP have a greatly increased risk of
developing colon cancer before age 40.
* Hereditary nonpolyposis colorectal cancer (HNPCC). HNPCC, also
called Lynch syndrome, increases the risk of colon cancer and other
cancers. People with HNPCC tend to develop colon cancer before age 50.
Both FAP and HNPCC can be detected through genetic testing. If you're
concerned about your family's history of colon cancer, talk to your
doctor about whether your family history suggests you have a risk of
Factors that may increase your risk of colon cancer include:
* Older age. About 90 percent of people diagnosed with colon cancer
are older than 50. Colon cancer can occur in younger people, but it
occurs much less frequently.
* African-American race. African-Americans have a greater risk of colon cancer than do people of other races.
* A personal history of colorectal cancer or polyps. If you've
already had colon cancer or adenomatous polyps, you have a greater risk
of colon cancer in the future.
* Inflammatory intestinal conditions. Long-standing inflammatory
diseases of the colon, such as ulcerative colitis and Crohn's disease,
can increase your risk of colon cancer.
* Inherited syndromes that increase colon cancer risk. Genetic
syndromes passed through generations of your family can increase your
risk of colon cancer. These syndromes include familial adenomatous
polyposis and hereditary nonpolyposis colorectal cancer, which is also
known as Lynch syndrome.
* Family history of colon cancer and colon polyps. You're more
likely to develop colon cancer if you have a parent, sibling or child
with the disease. If more than one family member has colon cancer or
rectal cancer, your risk is even greater. In some cases, this connection
may not be hereditary or genetic. Instead, cancers within the same
family may result from shared exposure to an environmental carcinogen or
from diet or lifestyle factors.
* Low-fiber, high-fat diet. Colon cancer and rectal cancer may be
associated with a diet low in fiber and high in fat and calories.
Research in this area has had mixed results. Some studies have found an
increased risk of colon cancer in people who eat diets high in red meat
and processed meats.
* A sedentary lifestyle. If you're inactive, you're more likely to
develop colon cancer. Getting regular physical activity may reduce your
risk of colon cancer.
* Diabetes. People with diabetes and insulin resistance may have an increased risk of colon cancer.
* Obesity. People who are obese have an increased risk of colon
cancer and an increased risk of dying of colon cancer when compared with
people considered normal weight.
* Smoking. People who smoke cigarettes may have an increased risk of colon cancer.
* Alcohol. Heavy use of alcohol may increase your risk of colon cancer.
* Radiation therapy for cancer. Radiation therapy directed at the
abdomen to treat previous cancers may increase the risk of colon cancer.
Preparing for your appointment
If your doctor suspects you may have colon cancer, you'll likely be
referred to specialists who treat colon cancer. You may meet with a
number of specialists, including:
* Doctors who treat digestive diseases (gastroenterologists)
* Doctors who treat cancer (oncologists)
* Doctors who remove colon cancer using surgery (surgeons)
* Doctors who use radiation to treat cancer (radiation oncologists)
Because appointments can be brief, and because there's often a lot of
ground to cover, it's a good idea to be well prepared for your
appointment. Here's some information to help you get ready for your
appointment, and what to expect from your doctor.
What you can do
* Be aware of any pre-appointment restrictions. At the time you make
the appointment, be sure to ask if there's anything you need to do in
advance, such as restrict your diet.
* Write down any symptoms you're experiencing, including any that
may seem unrelated to the reason for which you scheduled the
* Write down key personal information, including any major stresses or recent life changes.
* Make a list of all medications, as well as any vitamins or supplements, that you're taking.
* Take a family member or friend along, if possible. Sometimes it
can be difficult to absorb all the information provided during an
appointment. Someone who accompanies you may remember something that you
missed or forgot.
* Write down questions to ask your doctor.
Your time with your doctor is limited, so preparing a list of questions
will help you make the most of your time together. List your questions
from most important to least important in case time runs out. For colon
cancer, some basic questions to ask your doctor include:
* Where is my colon cancer located in my colon?
* What is the stage of my colon cancer?
* Can you explain my pathology report to me?
* Can I have a copy of my pathology report?
* Has my colon cancer spread to other parts of my body?
* Will I need more tests?
* What are the treatment options for my colon cancer?
* Will any of the treatments cure my colon cancer?
* What is the chance that my colon cancer will be cured?
* How much does each treatment increase my chances that my colon cancer will be cured?
* What are the potential side effects of each treatment?
* How will each treatment affect my daily life?
* Is there one treatment you feel is best for me?
* What would you recommend to a family member or friend in my same situation?
* How much time can I take to make my decision about treatment?
* Should I seek a second opinion?
* Should I see a specialist? What will that cost, and will my insurance cover seeing a specialist?
* Are there any brochures or other printed material that I can take with me? What Web sites do you recommend?
In addition to the questions that you've prepared to ask your doctor,
don't hesitate to ask questions during your appointment at any time that
you don't understand something.
Tests and diagnosis
Diagnosing colon cancer
If your signs and symptoms indicate that you could have colon cancer,
your doctor may recommend one of more tests and procedures, including:
* Blood tests. Your doctor may order blood tests to better
understand what may be causing your signs and symptoms, but there are no
blood tests that can detect colon cancer. Blood tests may include a
complete blood count and organ-function tests.
* Using a scope to examine the inside of your colon. Colonoscopy
uses a long, flexible and slender tube attached to a video camera and
monitor to view your entire colon and rectum. If any suspicious areas
are found, your doctor can pass surgical tools through the tube to take
tissue samples (biopsies) for analysis.
* Using dye and X-rays to make a picture of your colon. A barium
enema allows your doctor to evaluate your entire colon with an X-ray.
Barium, a contrast dye, is placed into your bowel in an enema form.
During a double-contrast barium enema, air also is added. The barium
fills and coats the lining of the bowel, creating a clear silhouette of
your rectum, colon and sometimes a small portion of your small
* Using multiple CT images to create a picture of your colon.
Virtual colonoscopy combines multiple computerized tomography (CT)
images to create a detailed picture of the inside of your colon. If
you're unable to undergo colonoscopy, your doctor may recommend virtual
Staging colon cancer
Once you've been diagnosed with colon cancer, your doctor will then
order tests to determine the extent, or stage, of your cancer. Staging
helps determine what treatments are most appropriate for you. Staging
tests may include imaging procedures such as abdominal and chest CT
scans. In many cases, the stage of your cancer may not be determined
until after colon cancer surgery.
The stages of colon cancer are:
* Stage 0. Your cancer is in the earliest stage. It hasn't grown
beyond the inner layer (mucosa) of your colon or rectum. This stage of
cancer may also be called carcinoma in situ.
* Stage I. Your cancer has grown through the mucosa but hasn't spread beyond the colon wall or rectum.
* Stage II. Your cancer has grown into or through the wall of the colon or rectum but hasn't spread to nearby lymph nodes.
* Stage III. Your cancer has invaded nearby lymph nodes but isn't affecting other parts of your body yet.
* Stage IV. Your cancer has spread to distant sites, such as other organs — for instance to your liver or lung.
* Recurrent. This means your cancer has come back after treatment.
It may recur in your colon, rectum or other part of your body.
Treatments and drugs
The type of treatment your doctor recommends will depend largely on the
stage of your cancer. The three primary treatment options are: surgery,
chemotherapy and radiation.
Surgery for early-stage colon cancer
If your cancer is small, localized in a polyp and in a very early stage,
your doctor may be able to remove it completely during a colonoscopy.
If the pathologist determines that the cancer in the polyp doesn't
involve the base — where the polyp is attached to the bowel wall — then
there's a good chance that the cancer has been completely eliminated.
Some larger polyps may be removed using laparoscopic surgery. In this
procedure, your surgeon performs the operation through several small
incisions in your abdominal wall, inserting instruments with attached
cameras that display your colon on a video monitor. He or she may also
take samples from lymph nodes in the area where the cancer is located.
Surgery for invasive colon cancer
If your colon cancer has grown into or through your colon, your surgeon
may recommend a colectomy to remove the part of your colon that contains
the cancer, along with a margin of normal tissue on either side of the
cancer. Nearby lymph nodes are usually also removed and tested for
Your surgeon is often able to reconnect the healthy portions of your
colon or rectum. But when that's not possible, for instance if the
cancer is at the outlet of your rectum, you may need to have a permanent
or temporary colostomy. This involves creating an opening in the wall
of your abdomen from a portion of the remaining bowel for the
elimination of body waste into a special bag. Sometimes the colostomy is
only temporary, allowing your colon or rectum time to heal after
surgery. In some cases, however, the colostomy may be permanent.
Surgery for advanced cancer
If your cancer is very advanced or your overall health very poor, your
surgeon may recommend an operation to relieve a blockage of your colon
or other conditions in order to improve your symptoms. This type of
surgery is referred to as palliative surgery. The goal of palliative
surgery isn't to cure your cancer, but to relieve signs and symptoms,
such as bleeding and pain.
In specific cases where the cancer has spread only to the liver and if
your overall health is otherwise good, your doctor may recommend surgery
to remove the cancerous lesion from your liver. Chemotherapy may be
used before or after this type of surgery. This treatment may improve
Chemotherapy uses drugs to destroy cancer cells. Chemotherapy can be
used to destroy cancer cells after surgery, to control tumor growth or
to relieve symptoms of colon cancer. Your doctor may recommend
chemotherapy if your cancer has spread beyond the wall of the colon or
if your cancer has spread to the lymph nodes. In people with rectal
cancer, chemotherapy is typically used along with radiation therapy.
Radiation therapy uses powerful energy sources, such as X-rays, to kill
any cancer cells that might remain after surgery, to shrink large tumors
before an operation so that they can be removed more easily, or to
relieve symptoms of colon cancer and rectal cancer.
Radiation therapy is rarely used in early-stage colon cancer, but is a
routine part of treating rectal cancer, especially if the cancer has
penetrated through the wall of the rectum or traveled to nearby lymph
nodes. Radiation therapy, usually combined with chemotherapy, may be
used after surgery to reduce the risk that the cancer may recur in the
area of the rectum where it began.
Targeted drug therapy
Drugs that target specific defects that allow cancer cells to
proliferate are available to people with advanced colon cancer,
including bevacizumab (Avastin), cetuximab (Erbitux) and panitumumab
(Vectibix). Targeted drugs can be given along with chemotherapy or
alone. Targeted drugs are typically reserved for people with advanced
Some people are helped by targeted drugs, while others are not.
Researchers are working to determine who is most likely to benefit from
targeted drugs. Until then, doctors carefully weigh the limited benefit
of targeted drugs against the risk of side effects and the expensive
cost when deciding whether to use these treatments.
No complementary or alternative treatments have been found to cure colon cancer.
Alternative treatments may help you cope with a diagnosis of colon
cancer. Nearly all people with cancer experience some distress. Common
signs and symptoms of distress after your diagnosis might include
sadness, anger, difficulty concentrating, difficulty sleeping and loss
of appetite. Alternative treatments may help redirect your thoughts away
from your fears, at least temporarily, to give you some relief.
Alternative treatments that may help relieve distress include:
* Art therapy
* Dance or movement therapy
* Music therapy
* Relaxation exercises
Your doctor can refer you to professionals who can help you learn about
and try these alternative treatments. Tell your doctor if you're
Coping and support
A diagnosis of cancer can be extremely challenging. Even when a full
recovery is likely, you may worry about a recurrence of the disease. But
no matter what your concerns or prognosis, you're not alone. Here are
some strategies and resources that may make dealing with cancer easier:
* Know what to expect. Find out everything you need to know about
your cancer in order to make treatment decisions. Ask your doctor to
tell you the type and stage of your cancer, as well as your treatment
options and their side effects. The more you know, the more confident
you'll be when it comes to making decisions about your own care. Look
for information in your local library and on reliable Web sites on the
Internet. The National Cancer Institute (NCI) answers questions from the
public. You can reach the NCI at 800-4-CANCER (800-422-6237). Or
contact the American Cancer Society (ACS) at 800-227-2345.
* Maintain a strong support system. Friends and family can be your
best allies as you face your cancer diagnosis. They often want to help,
so take them up on offers to make meals or provide transportation to and
from appointments. Sometimes the concern and understanding of a formal
support group or other cancer survivors can offer unique emotional
support. You may also find you develop deep and lasting bonds with
people who are going through the same things you are. There are also
support groups for the families of cancer survivors.
* Set reasonable goals. Having goals helps you feel in control and
can give you a sense of purpose. But don't choose goals you can't
possibly reach. You may not be able to work a 40-hour week, for example,
but you may be able to work at least half time. In fact, many people
find that continuing to work can be helpful.
* Take time for yourself. Eating well, relaxing and getting enough
rest can help combat the stress and fatigue of cancer. Also, plan ahead
for the downtimes when you may need to rest more or limit what you do.
Get screened for colon cancer
Regular colon cancer screening should begin at age 50 for people at
average risk of colon cancer. The American College of Gastroenterology
recommends African-Americans, who have an increased risk of colon
cancer, begin screening at age 45. Several screening options exist —
each with its own benefits and drawbacks. Talk about your options with
your doctor, and together you can decide which tests are appropriate for
Guidelines issued by the American Cancer Society, the U.S. Multi-Society
Task Force on Colorectal Cancer and the American College of Radiology
include several options for colon cancer screening:
* Annual fecal occult blood testing
* Flexible sigmoidoscopy every five years
* Double-contrast barium enema every five years
* Colonoscopy every 10 years
* Virtual colonoscopy (CT colonography) every five years
* Stool DNA testing — new screening approach; test is available, but
not certified by the Food and Drug Administration; research under way
to increase accuracy and determine how often test should be done
More frequent or earlier screening may be recommended if you're at
increased risk of colon cancer. Discuss the benefits and risks of each
screening option with your doctor. You may decide one or more tests are
appropriate for you. One factor to consider is whether your health
insurance covers colon cancer screening.
Medicare covers colon cancer screening procedures. If you're older than
50 and have Medicare benefits, Medicare will cover annual fecal occult
blood tests and sigmoidoscopy every four years. If you're at high risk
of colorectal cancer, you'll be covered for colonoscopy every two years,
or every 10 years if you're of average risk. Double-contrast barium
enema — which is sometimes supplemented with flexible sigmoidoscopy —
can be used as an alternative, if your doctor thinks it's a better
choice for you.
Make lifestyle changes to reduce your risk
You can take steps to reduce your risk of colon cancer by making changes in your everyday life. Take steps to:
* Eat a variety of fruits, vegetables and whole grains. Fruits,
vegetables and whole grains contain vitamins, minerals, fiber and
antioxidants, which may play a role in cancer prevention. Choose a
variety of fruits and vegetables so that you get an array of vitamins
* Drink alcohol in moderation, if at all. If you choose to drink
alcohol, limit the amount of alcohol you drink to no more than one drink
a day for women and two for men.
* Stop smoking. Talk to your doctor about ways to quit that may work for you.
* Exercise most days of the week. Try to get at least 30 minutes of
exercise on most days. If you've been inactive, start slowly and build
up gradually to 30 minutes. Also, talk to your doctor before starting
any exercise program.
* Maintain a healthy weight. If you have a healthy weight, work to
maintain your weight by combining a healthy diet with daily exercise. If
you need to lose weight, ask your doctor about healthy ways to achieve
your goal. Aim to lose weight slowly by increasing the amount of
exercise you get and reducing the number of calories you eat.
Colon cancer prevention for people with a high risk
Some treatments, including medications and surgery, have been found to
reduce the risk of precancerous polyps or colon cancer. However, not
enough evidence exists to recommend these medications to people who have
an average risk of colon cancer. If you have an increased risk of colon
cancer, you might discuss the benefits and risks of these preventive
treatments with your doctor:
* Aspirin. Some evidence links a reduced risk of polyps and colon
cancer to regular aspirin use. However, studies of low-dose aspirin or
short-term use of aspirin haven't found this to be true. It's likely
that you may be able to reduce your risk of colon cancer by taking large
doses of aspirin over a long period of time. But using aspirin in this
way is likely to cause side effects, such as gastrointestinal bleeding
* Nonsteroidal anti-inflammatory drugs (NSAIDs) other than aspirin.
This class of pain-relief medications includes drugs such as ibuprofen
(Advil, Motrin, others) and naproxen (Aleve, others). Some studies have
found NSAIDs may reduce the risk of precancerous polyps and colon
cancer. But side effects include ulcers and gastrointestinal bleeding.
Some NSAIDs have been linked to an increased risk of heart problems.
* Celecoxib (Celebrex). Celecoxib and other drugs known as COX-2
inhibitors work similarly to NSAIDs to provide pain relief. Some
evidence suggests COX-2 drugs can reduce the risk of precancerous polyps
in people who've been diagnosed with these polyps in the past. But
COX-2 drugs carry a risk of heart problems, including heart attack. Two
COX-2 inhibitor drugs were removed from the market because of these
* Surgery to prevent cancer. In cases of rare, inherited syndromes
such as familial adenomatous polyposis, or inflammatory bowel disease
such as ulcerative colitis, your doctor may recommend removal of your
entire colon and rectum in order to prevent cancer from occurring in the