- Introduction
- The Stomach
- What Is Cancer?
- Causes of Stomach Cancer
- Recognizing Symptoms
- Diagnosing
- Staging
- Orthodox Treatment
- Side Effects of Treatment
Introduction
Each year, about 24,000 people in the United States learn
that they have cancer of the stomach. This booklet will give
you important information about the symptoms, diagnosis, and
treatment of stomach cancer. It also has information to help
you deal with this disease if it affects you or someone you
know.
The Stomach
The stomach is part of the digestive system. It is located
in the upper abdomen, under the ribs. The upper part of the
stomach connects to the esophagus, and the lower part leads
into the small intestine.
When food enters the stomach, muscles in the stomach wall
create a rippling motion that mixes and mashes the food. At
the same time, juices made by glands in the lining of the
stomach help digest the food. After about 3 hours, the food
becomes a liquid and moves into the small intestine, where
digestion continues.
What Is Cancer?
Cancer is a group of more than 100 different diseases. They
affect the body's basic unit, the cell. Cancer occurs when
cells become abnormal and divide without control or order.
Like all other organs of the body, the stomach is made up
of many types of cells. Normally, cells divide to produce
more cells only when the body needs them. This orderly process
helps keep us healthy.
If cells keep dividing when new cells are not needed, a mass
of tissue forms. This mass of extra tissue, called a growth
or tumor, can be benign or malignant.
Benign tumors are not cancer. They can usually be
removed and, in most cases, they do not come back. Most important,
cells from benign tumors do not spread to other parts of the
body. Benign tumors are rarely a threat to life.
Malignant tumors are cancer. Cancer cells can invade
and damage tissues and organs near the tumor. Also, cancer
cells can break away from a malignant tumor and enter the
bloodstream or lymphatic system. This is how cancer spreads
from the original (primary) tumor to form new tumors in other
parts of the body. The spread of cancer is called metastasis.
Stomach cancer (also called gastric cancer) can develop in
any part of the stomach and may spread throughout the stomach
and to other organs. It may grow along the stomach wall into
the esophagus or small intestine.
It also may extend through the stomach wall and spread to
nearby lymph nodes and to organs such as the liver, pancreas,
and colon. Stomach cancer also may spread to distant organs,
such as the lungs, the lymph nodes above the collarbone, and
the ovaries.
When cancer spreads to another part of the body, the new
tumor has the same kind of abnormal cells and the same name
as the primary tumor. For example, if stomach cancer spreads
to the liver, the cancer cells in the liver are stomach cancer
cells. The disease is metastatic stomach cancer (it is not
liver cancer). However, when stomach cancer spreads to an
ovary, the tumor in the ovary is called a Krukenberg tumor.
(This tumor, named for a doctor, is not a different disease;
it is metastatic stomach cancer. The cancer cells in a Krukenberg
tumor are stomach cancer cells, the same as the cancer cells
in the primary tumor.)
Causes of Stomach Cancer
The stomach cancer rate in the United States and the number
of deaths from this disease have gone down dramatically over
the past 60 years. Still, stomach cancer is a serious disease,
and scientists all over the world are trying to learn more
about what causes this disease and how to prevent it. At this
time, doctors cannot explain why one person gets stomach cancer
and another does not. They do know, however, that stomach
cancer is not contagious; no one can "catch" cancer
from another person.
Researchers have learned that some people are more likely
than others to develop stomach cancer. The disease is found
most often in people over age 55. It affects men twice as
often as women, and is more common in black people than in
white people. Also, stomach cancer is more common in some
parts of the world--such as Japan, Korea, parts of Eastern
Europe, and Latin America--than in the United States. People
in these areas eat many foods that are preserved by drying,
smoking, salting, or pickling. Scientists believe that eating
foods preserved in these ways may play a role in the development
of stomach cancer. On the other hand, fresh foods (especially
fresh fruits and vegetables and properly frozen or refrigerated
fresh foods) may protect against this disease.
Stomach ulcers do not appear to increase a person's risk
(chance) of getting stomach cancer. However, some studies
suggest that a type of bacteria, Helicobacter pylori, which
may cause stomach inflammation and ulcers, may be an important
risk factor for this disease. Also, research shows that people
who have had stomach surgery or have pernicious anemia, achlorhydria,
or gastric atrophy (which generally result in lower than normal
amounts of digestive juices) have an increased risk of stomach
cancer.
Exposure to certain dusts and fumes in the workplace has
been linked to a higher than average risk of stomach cancer.
Also, some scientists believe smoking may increase stomach
cancer risk.
Recognizing Symptoms
Stomach cancer can be hard to find early. Often there are
no symptoms in the early stages and, in many cases, the cancer
has spread before it is found. When symptoms do occur, they
are often so vague that the person ignores them. Stomach cancer
can cause the following:
- Indigestion or a burning sensation (heartburn);
- Discomfort or pain in the abdomen;
- Nausea and vomiting;
- Diarrhea or constipation;
- Bloating of the stomach after meals;
- Loss of appetite;
- Weakness and fatigue; and
- Bleeding (vomiting blood or having blood in the stool).
Any of these symptoms may be caused by cancer or by other,
less serious health problems, such as a stomach virus or an
ulcer. Only a doctor can tell the cause. People who have any
of these symptoms should see their doctor. They may be referred
to a gastroenterologist, a doctor who specializes in diagnosing
and treating digestive problems. These doctors are sometimes
called gastrointestinal (or GI) specialists.
Diagnosing
To find the cause of symptoms, the doctor asks about the
patient's medical history, does a physical exam, and may order
laboratory studies. The patient may also have one or all of
the following exams:
Fecal occult blood test--a check for hidden (occult)
blood in the stool. This test is done by placing a small amount
of stool on a plastic slide or on special paper. It may be
tested in the doctor's office or sent to a laboratory. This
test is done because stomach cancer sometimes causes bleeding
that cannot be seen. However, noncancerous conditions also
may cause bleeding, so having blood in the stool does not
necessarily mean that a person has cancer.
Upper GI series--x-rays of the esophagus and stomach
(the upper gastrointestinal, or GI, tract. The x-rays are
taken after the patient drinks a barium solution, a thick,
chalky liquid. (This test is sometimes called a barium swallow.)
The barium outlines the stomach on the x-rays, helping the
doctor find tumors or other abnormal areas. During the test,
the doctor may pump air into the stomach to make small tumors
easier to see.
Endoscopy --an exam of the esophagus and stomach using
a thin, lighted tube called a gastroscope, which is passed
through the mouth and esophagus to the stomach. The patient's
throat is sprayed with a local anesthetic to reduce discomfort
and gagging. Patients also may receive medicine to relax them.
Through the gastroscope, the doctor can look directly at the
inside of the stomach. If an abnormal area is found, the doctor
can remove some tissue through the gastroscope. Another doctor,
a pathologist, examines the tissue under a microscope to check
for cancer cells. This procedure--removing tissue and examining
it under a microscope--is called a biopsy. A biopsy is the
only sure way to know whether cancer cells are present.
Staging
If the pathologist finds cancer cells in the tissue sample,
the patient's doctor needs to know the stage, or extent, of
the disease. Staging exams and tests help the doctor find
out whether the cancer has spread and, if so, what parts of
the body are affected. Because stomach cancer can spread to
the liver, the pancreas, and other organs near the stomach
as well as to the lungs, the doctor may order a CT (or CAT)
scan, an ultrasound exam, or other tests to check these areas.
Staging may not be complete until after surgery. The surgeon
removes nearby lymph nodes and may take samples of tissue
from other areas in the abdomen. All of these samples are
examined by a pathologist to check for cancer cells. Decisions
about treatment after surgery depend on these findings.
Orthodox Treatment
Cancer of the stomach is difficult to cure unless it is found
in an early stage (before it has begun to spread). Unfortunately,
because early stomach cancer causes few symptoms, the disease
is usually advanced when the diagnosis is made. However, advanced
stomach cancer can be treated and the symptoms can be relieved.
Treatment for stomach cancer may include surgery, chemotherapy,
and/or radiation therapy. New treatment approaches such as
biological therapy and improved ways of using current methods
are being studied in clinical trials. A patient may have one
form of treatment or a combination of treatments.
Surgery is the most common treatment for stomach cancer.
The operation is called gastrectomy. The surgeon removes part
(subtotal or partial gastrectomy) or all (total gastrectomy)
of the stomach, as well as some of the tissue around the stomach.
After a subtotal gastrectomy, the doctor connects the remaining
part of the stomach to the esophagus or the small intestine.
After a total gastrectomy, the doctor connects the esophagus
directly to the small intestine. Because cancer can spread
through the lymphatic system, lymph nodes near the tumor are
often removed during surgery so that the pathologist can check
them for cancer cells. If cancer cells are in the lymph nodes,
the disease may have spread to other parts of the body.
Chemotherapy is the use of drugs to kill cancer cells.
This type of treatment is called systemic therapy because
the drugs enter the bloodstream and travel through the body.
Clinical trials are in progress to find the best ways to
use chemotherapy to treat stomach cancer. Scientists are exploring
the benefits of giving chemotherapy before surgery to shrink
the tumor, or as adjuvant therapy after surgery to destroy
remaining cancer cells. Combination treatment with chemotherapy
and radiation therapy is also under study. Doctors are testing
a treatment in which anticancer drugs are put directly into
the abdomen (intraperitoneal chemotherapy). Chemotherapy also
is being studied as a treatment for cancer that has spread,
and as a way to relieve symptoms of the disease.
Most anticancer drugs are given by injection; some are taken
by mouth. The doctor may use one drug or a combination of
drugs. Chemotherapy is given in cycles: a treatment period
followed by a recovery period, then another treatment, and
so on. Usually a person receives chemotherapy as an outpatient
(at the hospital, at the doctor's office, or at home). However,
depending on which drugs are given and the patient's general
health, a short hospital stay may be needed.
Radiation therapy (also called radiotherapy) is the
use of high-energy rays to damage cancer cells and stop them
from growing. Like surgery, it is local therapy; the radiation
can affect cancer cells only in the treated area. Radiation
therapy is sometimes given after surgery to destroy cancer
cells that may remain in the area. Researchers are conducting
clinical trials to find out whether it is helpful to give
radiation therapy during surgery (intraoperative radiation
therapy). Radiation therapy may also be used to relieve pain
or blockage
Side Effects of Orthodox Treatment
It is hard to limit the effects of therapy so that only cancer
cells are removed or destroyed. Because healthy cells and
tissues also may be damaged, treatment can cause unpleasant
side effects.
The side effects of cancer treatment are different for each
person, and they may even be different from one treatment
to the next. Doctors try to plan treatment in ways that keep
side effects to a minimum; they can help with any problems
that occur. For this reason, it is very important to let the
doctor know about any problems during or after treatment.
Surgery
Gastrectomy is major surgery. For a period of time after the
surgery, the person's activities are limited to allow healing
to take place. For the first few days after surgery, the patient
is fed intravenously (through a vein). Within several days,
most patients are ready for liquids, followed by soft, then
solid, foods. Those who have had their entire stomach removed
cannot absorb vitamin B12, which is necessary for healthy
blood and nerves, so they need regular injections of this
vitamin. Patients may have temporary or permanent difficulty
digesting certain foods, and they may need to change their
diet. Some gastrectomy patients will need to follow a special
diet for a few weeks or months, while others will need to
do so permanently. The doctor or a dietitian (a nutrition
specialist) will explain any necessary dietary changes.
Some gastrectomy patients have cramps, nausea, diarrhea,
and dizziness shortly after eating because food and liquid
enter the small intestine too quickly. This group of symptoms
is called the dumping syndrome. Foods containing high amounts
of sugar often make the symptoms worse. The dumping syndrome
can be treated by changing the patient's diet. Doctors often
advise patients to eat several small meals throughout the
day, to avoid foods that contain sugar, and to eat foods high
in protein. To reduce the amount of fluid that enters the
small intestine, patients are usually encouraged not to drink
at mealtimes. Medicine also can help control the dumping syndrome.
The symptoms usually disappear in 3 to 12 months, but they
may be permanent.
Following gastrectomy, bile in the small intestine may back
up into the remaining part of the stomach or into the esophagus,
causing the symptoms of an upset stomach. The patient's doctor
may prescribe medicine or suggest over-the-counter products
to control such symptoms.
Chemotherapy
The side effects of chemotherapy depend mainly on the drugs
the patient receives. As with any other type of treatment,
side effects also vary from person to person. In general,
anticancer drugs affect cells that divide rapidly. These include
blood cells, which fight infection, help the blood to clot,
or carry oxygen to all parts of the body. When blood cells
are affected by anticancer drugs, patients are more likely
to get infections, may bruise or bleed easily, and may have
less energy. Cells in hair roots and cells that line the digestive
tract also divide rapidly. As a result of chemotherapy, patients
may have side effects such as loss of appetite, nausea, vomiting,
hair loss, or mouth sores. For some patients, the doctor may
prescribe medicine to help with side effects, especially with
nausea and vomiting. These effects usually go away gradually
during the recovery period between treatments or after the
treatments stop.
Radiation Therapy
Patients who receive radiation to the abdomen may have nausea,
vomiting, and diarrhea. The doctor can prescribe medicine
or suggest dietary changes to relieve these problems. The
skin in the treated area may become red, dry, tender, and
itchy. Patients should avoid wearing clothes that rub; loose-fitting
cotton clothes are usually best. It is important for patients
to take good care of their skin during treatment, but they
should not use lotions or creams without the doctor's advice.
Patients are likely to become very tired during radiation
therapy, especially in the later weeks of treatment. Resting
is important, but doctors usually advise patients to try to
stay as active as they can.
Biological Therapy
The side effects of biological therapy vary with the type
of treatment. Some cause flu-like symptoms, such as chills,
fever, weakness, nausea, vomiting, and diarrhea. Patients
sometimes get a rash, and they may bruise or bleed easily.
These problems may be severe, and patients may need to stay
in the hospital during treatment.
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