|
Colon
Cancer
Introduction
What is colorectal cancer?
Who is at risk?
What are screening tests, and why are they
so important?
What tests are used to screen people for colorectal
cancer?
Do insurance companies pay for colorectal cancer
screening?
Does colorectal cancer cause symptoms?
How is colorectal cancer diagnosed?
How is colorectal cancer treated?
Do patients with colorectal cancer participate
in clinical trials (research studies)?
Introduction
People assume they have "piles" or hemorrhoids whenever
there is any symptom in the rectal area. This is a misconception.
A study done at the Hemorrhoid Care Medical Clinic in 1988, showed
that approximately 90% of colon and rectal cancer patients initially
thought that they had hemorrhoids, and presented with symptoms
of rectal itching and rectal bleeding. Other warning signs of
colon cancer are:
- Excess
Gas
- Constipation
- Blood
in Stools
- Change
in Bowel Habits
- Persistent
Abdominal Discomfort
- Change
in Shape of Color of Stools
- Sensation
of Incomplete Evacuation
- Feelings
of Tiredness or Exhaustion
Cancer
of the colon and rectum is the second most common cause of cancer
death in the U.S.A. today. 1 out of every 17 Americans will get
colorectal cancer at some point in their life. Early diagnosis
is the key to achieving survival. With better diagnostic modalities
and more aggressive approaches, we can improve the present rate
of survival from 62% to 81%, which means an additional 56,000
patients will live each year.
According
to the American Cancer Society (ACS), 90% of all colorectal cancer
cases and deaths are thought to be preventable, based on existing
approaches to prevention and early detection. Screening tests
that detect occult blood in the stool or identify adenomatous
polyps can prevent the occurrence of colorectal cancers by allowing
the detection and removal of pre-cancerous lesions before they
undergo malignant transformation.
Approximately
the five-year survival rate for colon cancer is 90% when it is
diagnosed at an early, localized stage. However, only 37% of diagnoses
are made in the early stage. As a result, colon cancer is the
second deadliest cancer in the US.
Get
the test. Get the polyp. Get the cure.
Colon
cancer almost always starts with a colon
polyp, developing with no symptoms. Finding and removing polyps
through early detection testing before they become cancerous can
stop colon cancer before it even starts. In fact, if all Americans
50 years of age or older had regular tests, annual deaths from
colon cancer could be cut in half.
The
death rate from colorectal cancer has been going down for the
past 20 years. This may be because there are fewer cases, because
more of the cases are found early, and also because treatments
have improved.
That
is why for most proctologists and gastrointestinal specialists,
the diagnosis and treatment of colorectal cancer is a priority
concern.
Questions
and Answers About Screening,
Early Detection, and Treatment for Colorectal Cancer
top
What
is colorectal cancer?
Cancer that begins in the colon is called colon cancer, and cancer
that begins in the rectum is called rectal cancer. Cancers affecting
either of these organs may also be called colorectal cancer.
The
colon and rectum are parts of the body's digestive system, which
removes nutrients from food and stores waste until it passes out
of the body. Together, the colon and rectum form a long, muscular
tube called the large intestine (also called the large bowel).
The colon is the first 6 feet of the large intestine, and the
rectum is the last 8 to 10 inches.
Colon, rectum, and other parts of digestive system
Colorectal
cancer is a disease in which cells in the colon or rectum become
abnormal and divide without control or order, forming a mass called
a tumor. Tumors can be either benign or malignant.
Benign
tumors are not cancer. They often can be removed and, in most
cases, they do not come back. Cells in benign tumors do not spread
to other parts of the body. Most important, benign tumors are
rarely a threat to life.
Malignant
tumors are cancer. Cells in malignant tumors are abnormal
and divide without control or order. These cancer cells can invade
and destroy the tissue around them. Cancer cells can also break
away from a malignant tumor. They may enter the bloodstream or
lymphatic system (the tissues and organs that produce and store
cells that fight infection and disease). This process, called
metastasis, is how cancer spreads from the original (primary)
tumor to form new (secondary) tumors in other parts of the body.
top
Who
is at risk?
The exact causes of colorectal cancer are not known. However,
studies show that certain factors increase a person's chance of
developing colorectal cancer:
Age.
Colorectal cancer is more likely to occur as people get older.
Most people who develop colorectal cancer are over the age of
50. However, the disease can occur at any age.
Diet.
The development of colorectal cancer seems to be associated
with a diet that is high in fat and calories and low in foods
with fiber , such as whole grains, fruits, and vegetables. Researchers
are exploring how these and other dietary components play a role
in the development of colorectal cancer.
Polyps.
Polyps are benign growths
(not cancer) on the inner wall of the colon or rectum. They are
relatively common in people over age 50. Because most colorectal
cancers develop in polyps, detecting and removing these growths
may be a way to prevent colorectal cancer. Familial polyposis
is a rare, inherited condition in which hundreds of polyps develop
in the colon and rectum. Unless this condition is treated, a person
who has it is extremely likely to develop colorectal cancer.
Personal
history. A person who has already had colorectal cancer may
develop colorectal cancer a second time. Also, research studies
show that women with a history of ovarian, uterine, or breast
cancer have a somewhat increased chance of developing colorectal
cancer.
Family
history. Close relatives (parents, siblings, or children)
of a person who has had colorectal cancer are somewhat more likely
to develop this type of cancer themselves, especially if the relative
developed the cancer at a young age. If many family members have
had colorectal cancer, the chances increase even more.
Ulcerative
colitis. Ulcerative
colitis is a condition in which the lining of the colon becomes
inflamed. People who have ulcerative colitis are more likely to
develop colorectal cancer.
top
What are screening tests, and why are they so important?
Screening tests are examinations that check for health problems
before they cause symptoms. Screening tests are important because
finding health problems at an early stage often means that treatment
will be more successful.
Colorectal
cancer screening tests are used to detect cancer, polyps that
may eventually become cancerous, or other abnormal conditions.
Most
people who undergo colorectal screening do not have any colorectal
abnormality. For those who do, diagnosis and treatment can occur
promptly.
top
What
tests are used to screen people for colorectal cancer?
People who have any risk factors for colorectal cancer should
ask their doctor when to begin screening for colorectal cancer,
what tests to have, and how often to schedule appointments. Doctors
may suggest one or more of the tests listed below as a part of
regular checkups.
A
fecal occult blood test (FOBT) is a test for hidden blood in the
stool. This test has been proven to reduce the death rate
of colorectal cancer.
A
sigmoidoscopy is an examination of the rectum and lower
colon with a lighted instrument.
A
colonoscopy
is an examination of the rectum and entire colon with a lighted
instrument.
A
double contrast barium enema is a series of x-rays of the
colon and rectum. The x-rays are taken after the patient is given
an enema with a white, chalky solution that contains barium to
outline the colon and rectum on the x-rays.
A digital rectal exam (DRE) is a test in which the doctor
inserts a lubricated, gloved finger into the rectum to feel for
abnormal areas.
top
Do
insurance companies pay for colorectal cancer screening?
People should check with their health insurance provider to determine
their colorectal cancer screening benefits. People who are age
50 or older and are covered by Medicare are eligible for colorectal
cancer screening benefits. Additional information is available
on the Medicare Web site at http://www.medicare.gov/health/overview.asp
on the Internet.
top
Does
colorectal cancer cause symptoms?
Common symptoms of colorectal cancer include the following:
- Change
in bowel habits
- Diarrhea,
constipation, or feeling that the bowel does not empty completely
- Blood
in the stool (either bright red or very dark in color)
- Stools
that are narrower than usual
- General
abdominal discomfort (frequent gas pains, bloating, fullness,
and/or cramps)
- Weight
loss with no known reason
- Constant
tiredness
- Vomiting
These
symptoms can be caused by cancer or by a number of other conditions.
It is important to check with a doctor.
top
How
is colorectal cancer diagnosed?
To find the cause of symptoms, the doctor evaluates one's personal
and family medical history. The doctor also performs a physical
exam and may order one or more diagnostic tests. These may include
a blood test called a CEA assay to measure a protein called carcinoembryonic
antigen that is sometimes higher in patients with colorectal cancer.
The doctor may also order x-rays of the gastrointestinal tract
, sigmoidoscopy , or colonoscopy. If abnormal tissue is found
during these tests, a biopsy (the removal of tissue for examination
under a microscope by a pathologist) is performed to determine
if a person has cancer.
If the diagnosis is cancer, the doctor will want to learn the
stage (or extent) of disease. Staging is a careful attempt to
find out whether the cancer has spread and, if so, to what parts
of the body. Knowing the stage of the disease helps the doctor
plan treatment. Additional tests may be performed to help determine
the stage.
top
How
is colorectal cancer treated?
Treatment for colorectal cancer depends on a number of factors,
including the general health of the patient and the size, location,
and extent of the tumor. Many different treatments and combinations
of treatments are used to treat colorectal cancer.
Surgery
to remove the cancer is the most common treatment for colorectal
cancer. The type of surgery that a doctor performs depends mainly
on where the cancer is found.
Chemotherapy
is the use of anticancer drugs to kill cancer cells. The anticancer
drugs circulate in the bloodstream and affect cancer cells throughout
the body.
Radiation
therapy, also called radiotherapy, involves the use of high-energy
x-rays to kill cancer cells. Radiation therapy affects the cancer
cells only in the treated area.
Biological
therapy, also called immunotherapy, uses the body's immune
system, either directly or indirectly, to fight cancer. The immune
system recognizes cancer cells in the body and works to eliminate
them. Biological therapies are designed to repair, stimulate,
or enhance the immune system's natural anticancer function.
top
Do
patients with colorectal cancer participate in clinical trials
(research studies)?
Yes, patients with all stages of colorectal cancer can take part
in clinical trials (research studies). Clinical trials to evaluate
new ways to treat cancer are an appropriate treatment option for
many patients with this disease. Through research, doctors learn
new ways to treat cancer that may be more effective than the standard
therapy. Research has led to significant advances in the treatment
of colorectal cancer. Information about ongoing clinical trials
is available from the Cancer Information Service (see below),
or from the National Cancer Institute's cancerTrials Web site
at http://cancertrials.nci.nih.gov on the Internet.
Cancer
Information Service
Toll-free: 1-800-4-CANCER (1-800-422-6237)
TTY (for deaf and hard of hearing callers): 1-800-332-8615
top
|
