Cancer Awareness in Pakistan - Colon and rectal Cancer

What You Need
To Know AboutTM
Cancer
National Cancer Institute
of the
Colon
and
Rectum
U.S. DEPARTMENT OF
HEALTH AND HUMAN SERVICES
National Institutes of Health

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Contents
About This Booklet 1
The Colon and Rectum 2
Understanding Cancer 3
Risk Factors 4
Screening 7
Symptoms 9
Diagnosis 9
Staging 11
Treatment 13
Nutrition and Physical Activity 25
Rehabilitation 26
Follow-up Care 26
Complementary Medicine 27
Sources of Support 28
The Promise of Cancer Research 29
Dictionary 32
National Cancer Institute Information Resources 42
National Cancer Institute Publications 43
U.S. DEPARTMENT OF HEALTH AND
HUMAN SERVICES
National Institutes of Health
National Cancer Institute

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About This Booklet
This National Cancer Institute (NCI) booklet is
about cancer of the colon and rectum. Cancer that
begins in the colon is called colon cancer, and cancer
that begins in the rectum is called rectal cancer. Cancer
that starts in either of these organs may also be called
colorectal cancer.
In the United States, colorectal cancer is the fourth
most common cancer in men, after skin, prostate, and
lung cancer. It is also the fourth most common cancer
in women, after skin, breast, and lung cancer.
You will read about possible risk factors, screening,
symptoms, diagnosis, and treatment. You will also find
lists of questions to ask your doctor. It may help to take
this booklet with you to your next appointment.
Important terms appear in italics. The Dictionary at
the back of this booklet explains these terms. Most
words in the Dictionary have a “sounds-like” spelling
to show how to pronounce them. Also, definitions of
more than 4,000 terms are on the NCI Web site in the
NCI Dictionary of Cancer Terms. You can access it at
http://www.cancer.gov/dictionary.
If you want more information about colorectal can-
cer, please visit our Web site at http://www.cancer.gov/
cancertopics/types/colon-and-rectal. Or, contact our
Cancer Information Service. We can answer your
questions about cancer. We can send you NCI booklets,
fact sheets, and other materials. You can call
1–800–4–CANCER (1–800–422–6237) or instant
message us through the LiveHelp service at
http://www.cancer.gov/help.
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The Colon and Rectum
The colon and rectum are parts of the digestive
system. They form a long, muscular tube called the
large intestine (also called the large bowel). The colon
is the first 4 to 5 feet of the large intestine, and the
rectum is the last several inches.
Partly digested food enters the colon from the small
intestine. The colon removes water and nutrients from
the food and turns the rest into waste (stool). The waste
passes from the colon into the rectum and then out of
the body through the anus.
Stomach
Small
intestine
Colon
Rectum
Lymph
nodes
Anus
This picture shows the colon and rectum.
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Understanding Cancer
Cancer begins in cells, the building blocks that make
up tissues. Tissues make up the organs of the body.
Normally, cells grow and divide to form new cells
as the body needs them. When cells grow old, they die,
and new cells take their place.
Sometimes, this orderly process goes wrong. New
cells form when the body does not need them, and old
cells do not die when they should. These extra cells
can form a mass of tissue called a growth or tumor.
Tumors can be benign or malignant:
• Benign tumors are not cancer:
—Benign tumors are rarely life-threatening.
—Most benign tumors can be removed. They
usually do not grow back.
—Benign tumors do not invade the tissues around
them.
—Cells from benign tumors do not spread to other
parts of the body.
• Malignant tumors are cancer:
—Malignant tumors are generally more serious than
benign tumors. They may be life-threatening.
—Malignant tumors often can be removed. But
sometimes they grow back.
—Malignant tumors can invade and damage nearby
tissues and organs.
—Cancer cells can break away from a malignant
tumor and spread to other parts of the body.
Cancer cells spread by entering the bloodstream
or the lymphatic system. The cancer cells form
new tumors that damage other organs. The spread
of cancer is called metastasis.
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When colorectal cancer spreads outside the colon or
rectum, cancer cells are often found in nearby lymph
nodes. If cancer cells have reached these nodes, they
may also have spread to other lymph nodes or other
organs. Colorectal cancer cells most often spread to the
liver.
When cancer spreads from its original place to
another part of the body, the new tumor has the same
kind of abnormal cells and the same name as the
original tumor. For example, if colorectal cancer
spreads to the liver, the cancer cells in the liver are
actually colorectal cancer cells. The disease is
metastatic colorectal cancer, not liver cancer. For that
reason, it is treated as colorectal cancer, not liver
cancer. Doctors call the new tumor “distant” or
metastatic disease.
Risk Factors
No one knows the exact causes of colorectal cancer.
Doctors often cannot explain why one person develops
this disease and another does not. However, it is clear
that colorectal cancer is not contagious. No one can
catch this disease from another person.
Research has shown that people with certain risk
factors are more likely than others to develop
colorectal cancer. A risk factor is something that may
increase the chance of developing a disease.
Studies have found the following risk factors for
colorectal cancer:
• Age over 50: Colorectal cancer is more likely to
occur as people get older. More than 90 percent of
people with this disease are diagnosed after age 50.
The average age at diagnosis is 72.
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• Colorectal polyps: Polyps are growths on the inner
wall of the colon or rectum. They are common in
people over age 50. Most polyps are benign (not
cancer), but some polyps (adenomas) can become
cancer. Finding and removing polyps may reduce
the risk of colorectal cancer.
• Family history of colorectal cancer: Close
relatives (parents, brothers, sisters, or children) of a
person with a history of colorectal cancer are
somewhat more likely to develop this disease
themselves, especially if the relative had the cancer
at a young age. If many close relatives have a
history of colorectal cancer, the risk is even greater.
• Genetic alterations: Changes in certain genes
increase the risk of colorectal cancer.
—Hereditary nonpolyposis colon cancer (HNPCC)
is the most common type of inherited (genetic)
colorectal cancer. It accounts for about 2 percent
of all colorectal cancer cases. It is caused by
changes in an HNPCC gene. Most people with an
altered HNPCC gene develop colon cancer, and
the average age at diagnosis of colon cancer is 44.
—Familial adenomatous polyposis (FAP) is a rare,
inherited condition in which hundreds of polyps
form in the colon and rectum. It is caused by a
change in a specific gene called APC. Unless
FAP is treated, it usually leads to colorectal
cancer by age 40. FAP accounts for less than 1
percent of all colorectal cancer cases.
Family members of people who have HNPCC or
FAP can have genetic testing to check for specific
genetic changes. For those who have changes in
their genes, health care providers may suggest ways
to try to reduce the risk of colorectal cancer, or to
improve the detection of this disease. For adults
with FAP, the doctor may recommend an operation
to remove all or part of the colon and rectum.
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• Personal history of cancer: A person who has
already had colorectal cancer may develop
colorectal cancer a second time. Also, women with a
history of cancer of the ovary, uterus
(endometrium), or breast are at a somewhat higher
risk of developing colorectal cancer.
• Ulcerative colitis or Crohn’s disease: A person who
has had a condition that causes inflammation of the
colon (such as ulcerative colitis or Crohn’s disease)
for many years is at increased risk of developing
colorectal cancer.
• Diet: Studies suggest that diets high in fat
(especially animal fat) and low in calcium, folate,
and fiber may increase the risk of colorectal cancer.
Also, some studies suggest that people who eat a
diet very low in fruits and vegetables may have a
higher risk of colorectal cancer. However, results
from diet studies do not always agree, and more
research is needed to better understand how diet
affects the risk of colorectal cancer.
• Cigarette smoking: A person who smokes
cigarettes may be at increased risk of developing
polyps and colorectal cancer.
Because people who have colorectal cancer may
develop colorectal cancer a second time, it is important
to have checkups. If you have colorectal cancer, you
also may be concerned that your family members may
develop the disease. People who think they may be at
risk should talk to their doctor. The doctor may be able
to suggest ways to reduce the risk and can plan an
appropriate schedule for checkups. See the “Screening”
section on page 7 to learn more about tests that can
find polyps or colorectal cancer.
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Screening
Screening tests help your doctor find polyps or
cancer before you have symptoms. Finding and
removing polyps may prevent colorectal cancer. Also,
treatment for colorectal cancer is more likely to be
effective when the disease is found early.
To find polyps or early colorectal cancer:
• People in their 50s and older should be screened.
• People who are at higher-than-average risk of
colorectal cancer should talk with their doctor about
whether to have screening tests before age 50, what
tests to have, the benefits and risks of each test, and
how often to schedule appointments.
The following screening tests can be used to detect
polyps, cancer, or other abnormal areas. Your doctor
can explain more about each test:
• Fecal occult blood test (FOBT): Sometimes cancers
or polyps bleed, and the FOBT can detect tiny
amounts of blood in your stool. If this test detects
blood, other tests are needed to find the source of
the blood. Benign conditions (such as hemorrhoids)
also can cause blood in your stool.
• Sigmoidoscopy: Your doctor checks inside your
rectum and the lower part of the colon with a lighted
tube called a sigmoidoscope. If polyps are found,
your doctor removes them. The procedure to remove
polyps is called a polypectomy.
• Colonoscopy: Your doctor examines inside the
rectum and entire colon using a long, lighted tube
called a colonoscope. Your doctor removes polyps
that may be found.
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