Gastric (Stomach) Cancer
General Information About Gastric Cancer(Symptoms and diagnosis)
Stages of Gastric Cancer
Treatment Option Overview
Gastric (stomach) cancer is a disease in which malignant
(cancer) cells form in the lining of the stomach. The stomach is in the
upper abdomen and helps digest food.
Almost all gastric cancers are adenocarcinomas (cancers that
begin in cells that make and release mucus and other fluids). Other
types of gastric cancer are gastrointestinal carcinoid tumors,
gastrointestinal stromal tumors, and lymphomas.
Infection with bacteria called H. pylori
is a common cause of gastric cancer.
Gastric cancer is often diagnosed at an advanced stage because
there are no early signs or symptoms.
General Information About Gastric Cancer
Key Points
- Gastric cancer is a disease in which malignant (cancer)
cells form in the lining of the stomach.
- Age, diet, and stomach disease can affect the risk of
developing gastric cancer.
- Symptoms of gastric cancer include indigestion and stomach
discomfort or pain.
- Tests that examine the stomach and esophagus are used to
detect (find) and diagnose gastric cancer.
- Certain factors affect prognosis (chance of recovery) and
treatment options.
Gastric
cancer is a disease in which malignant (cancer) cells form in the
lining of the stomach.
The stomach is a J-shaped organ in the upper abdomen. It is part of the digestive system, which
processes nutrients
(vitamins, minerals, carbohydrates, fats, proteins, and water) in
foods that are eaten and helps pass waste material out of the body.
Food moves from the throat
to the stomach through a hollow, muscular tube called the esophagus. After leaving the
stomach, partly-digested food passes into the small intestine and then
into the large intestine.
The esophagus and stomach
are part of the upper gastrointestinal (digestive) system.
The wall of the stomach
is made up of 3 layers of tissue:
the mucosal
(innermost) layer, the muscularis (middle) layer, and the serosal (outermost) layer. Gastric cancer begins in the
cells lining the
mucosal layer and spreads through the outer layers as it grows.
Stromal tumors of the
stomach begin in supporting connective
tissue and are treated differently from gastric cancer. See the PDQ summary on
Gastrointestinal Stromal Tumors Treatment for more information.
For more information
about cancers of the stomach, see the following PDQ summaries:
- Unusual Cancers of Childhood Treatment
- Stomach (Gastric) Cancer Prevention
- Stomach (Gastric) Cancer Screening
Age,
diet, and stomach disease can affect the risk of developing gastric
cancer.
Anything that increases
your risk of getting a disease is called a risk
factor. Having a risk factor does not mean that you will
get cancer; not having risk factors doesn't mean that you will not get
cancer. Talk with your doctor if you think you may be at risk. Risk
factors for gastric cancer include the following:
- Having any of the following medical conditions:
- Helicobacter
pylori (H. pylori) infection
of the stomach.
- Chronic
gastritis (inflammation of the stomach).
- Pernicious
anemia.
- Intestinal
metaplasia
(a condition in which the normal stomach lining is replaced with the
cells that line the intestines).
- Familial
adenomatous polyposis (FAP) or gastric
polyps.
- Eating a diet
high in salted, smoked foods and low in fruits and vegetables.
- Eating foods that have not been prepared or stored properly.
- Being older or male.
- Smoking cigarettes.
- Having a mother, father, sister, or brother who has had stomach cancer.
Symptoms
of gastric cancer include indigestion and stomach discomfort or pain.
These and other signs and symptoms may be caused by
gastric cancer or by other conditions.
In the early stages of gastric cancer,
the following symptoms may occur:
- Indigestion and stomach discomfort.
- A bloated feeling after eating.
- Mild nausea.
- Loss of appetite.
- Heartburn.
In more advanced stages
of gastric cancer, the following signs and symptoms may occur:
- Blood
in the stool.
- Vomiting.
- Weight loss for no known reason.
- Stomach pain.
- Jaundice
(yellowing of eyes and skin).
- Ascites
(build-up of fluid
in the abdomen).
- Trouble swallowing.
Check with your doctor
if you have any of these problems.
Tests
that examine the stomach and esophagus are used to detect (find) and
diagnose gastric cancer.
The following tests and
procedures may be used:
- Physical
exam and history
: An exam of the body to check general signs of
health, including checking for signs of disease, such as lumps or
anything else that seems unusual. A history of the patient's health
habits and past illnesses and treatments will also be taken.
- Blood
chemistry studies : A procedure in which a
blood sample is checked to measure the amounts of certain substances
released into the blood by organs and tissues in the body. An unusual
(higher or lower than normal) amount of a substance can be a sign of
disease.
- Complete
blood count (CBC): A procedure in which a
sample of blood is drawn and checked for the following:
- The number of red
blood cells, white
blood cells, and platelets.
- The amount of hemoglobin
(the protein that carries oxygen)
in the red blood cells.
- The portion of the sample made up of red blood cells.
- Upper endoscopy
: A procedure to look inside the esophagus, stomach,
and duodenum (first
part of the small intestine) to check for abnormal
areas. An endoscope
(a thin, lighted tube) is passed through the mouth and down the throat
into the esophagus.
Upper endoscopy. A
thin, lighted tube is inserted through the mouth to look for abnormal
areas in the esophagus, stomach, and first part of the small intestine.
- Barium
swallow : A series of x-rays of the esophagus and
stomach. The patient drinks a liquid that contains barium (a silver-white metallic compound). The liquid coats
the esophagus and stomach, and x-rays are taken. This procedure is also
called an upper GI series.
Barium swallow for
stomach cancer. The patient swallows barium liquid and it flows through
the esophagus and into the stomach. X-rays are taken to look for
abnormal areas.
- CT
scan (CAT scan): A procedure that makes a
series of detailed pictures of areas inside the body, taken from
different angles. The pictures are made by a computer linked to an
x-ray machine. A dye
may be injected
into a vein or
swallowed to help the organs or tissues show up more clearly. This
procedure is also called computed tomography, computerized tomography,
or computerized axial tomography.
- Biopsy
: The removal of cells or tissues so they can be
viewed under a microscope
to check for signs of cancer. A biopsy of the stomach is usually done
during the endoscopy.
The sample of tissue
may be checked to measure how many HER2 genes there are and how much
HER2 protein is being made. If
there are more HER2 genes or higher levels of
HER2 protein than normal, the cancer is called HER2 positive. HER2-positive
gastric cancer may be treated with a monoclonal
antibody that targets the HER2 protein.
Certain
factors affect prognosis (chance of recovery) and treatment options.
The prognosis (chance of recovery) and treatment
options depend on the following:
- The stage of the cancer (whether it is in the stomach only
or has spread to lymph nodes
or other places in the body).
- The patient's general health.
Stages of Gastric Cancer
Key Points
- After gastric cancer has been diagnosed, tests are done to
find out if cancer cells have spread within the stomach or to other
parts of the body.
- There are three ways that cancer spreads in the body.
- Cancer may spread from where it began to other parts of the
body.
- The following stages are used for gastric cancer:
- Stage 0 (Carcinoma in Situ)
- Stage I
- Stage II
- Stage III
- Stage IV
After
gastric cancer has been diagnosed, tests are done to find out if cancer
cells have spread within the stomach or to other parts of the body.
The process used to find
out if cancer has
spread within the stomach
or to other
parts of the body is called staging.
The information gathered from the
staging process determines the stage
of the disease. It is important to know
the stage in order to plan treatment.
The following tests and
procedures may be used in the staging process:
- CEA
(carcinoembryonic antigen) assay: Tests that measure the
level of CEA in the blood.
This substance is released into the bloodstream from both cancer cells and normal cells. When
found in higher than normal amounts, it can be a sign of gastric cancer or other conditions.
- Endoscopic
ultrasound (EUS): A procedure in which an endoscope is inserted into
the body, usually through the mouth or rectum.
An endoscope is a thin, tube-like instrument with a light and a lens for viewing. A probe at
the end of the endoscope is used to bounce high-energy sound waves (ultrasound) off internal tissues or organs and make echoes. The
echoes form a picture of body tissues called a sonogram. This procedure is
also called endosonography.
- CT
scan (CAT scan): A procedure that makes a
series of detailed pictures of areas inside the body, taken from
different angles. The pictures are made by a computer linked to an
x-ray machine. A dye
may be injected
into a vein or
swallowed to help the organs or tissues show up more clearly. This
procedure is also called computed tomography, computerized tomography,
or computerized axial tomography.
- PET
scan (positron emission tomography scan): A
procedure to find malignant
tumor cells in
the body. A small amount of radioactive
glucose (sugar)
is injected into a vein. The PET scanner
rotates around the body and makes a picture of where glucose is being
used in the body. Malignant tumor cells show up brighter in the picture
because they are more active and take up more glucose than normal cells
do. A PET scan and CT scan may be done at the same time. This is called
a PET-CT.
There
are three ways that cancer spreads in the body.
Cancer can spread
through tissue, the
lymph system, and
the blood:
- Tissue. The cancer spreads from where it began by growing
into nearby areas.
- Lymph system. The cancer spreads from where it began by
getting into the lymph system. The cancer travels through the lymph vessels to other parts
of the body.
- Blood. The cancer spreads from where it began by getting
into the blood. The cancer travels through the blood vessels to other parts
of the body.
Cancer
may spread from where it began to other parts of the body.
When cancer spreads
to another part of the body, it is called metastasis.
Cancer cells break
away from where they began (the primary
tumor) and travel through the lymph system or blood.
- Lymph system. The cancer gets into the lymph system,
travels through the lymph vessels, and forms a tumor (metastatic tumor) in another
part of the body.
- Blood. The cancer gets into the blood, travels through the
blood vessels, and forms a tumor (metastatic tumor) in another part of
the body.
The metastatic tumor is
the same type of cancer as the primary tumor. For example, if gastric
cancer spreads to the liver,
the cancer cells in the liver are actually gastric cancer cells. The
disease is metastatic gastric cancer, not liver
cancer.
The
following stages are used for gastric cancer:
Stage
0 (Carcinoma in Situ)
In stage 0, abnormal cells are found in the
inside lining of the mucosa
(innermost layer) of the stomach
wall. These abnormal cells may become cancer
and spread into nearby normal tissue.
Stage 0 is also called carcinoma
in situ.
Stage
I
In stage I, cancer has formed in the
inside lining of the mucosa
(innermost layer) of the stomach
wall. Stage I is divided into stage IA and stage IB, depending on where
the cancer has spread.
- Stage IA:
Cancer may have spread into the submucosa
(layer of tissue
next to the mucosa)
of the stomach
wall.
- Stage IB:
Cancer:
- may have spread into the submucosa
(layer of tissue
next to the mucosa)
of the stomach wall
and is found in 1 or 2 lymph
nodes near the tumor;
or
- has spread to the muscle layer of the stomach wall.
Stage
II
Stage II gastric cancer is
divided into stage IIA and stage IIB, depending on where the cancer has spread.
- Stage IIA:
Cancer:
- has spread to the subserosa
(layer of tissue
next to the serosa)
of the stomach
wall; or
- has spread to the muscle layer of the stomach wall and
is found in 1 or 2 lymph nodes
near the tumor; or
- may have spread to the submucosa
(layer of tissue next to the mucosa)
of the stomach wall and is found in 3 to 6 lymph nodes near the tumor.
- Stage IIB:
Cancer:
- has spread to the serosa
(outermost layer) of the stomach
wall; or
- has spread to the subserosa
(layer of tissue
next to the serosa) of the stomach wall and is found in 1 or 2 lymph nodes near the tumor; or
- has spread to the muscle layer of the stomach wall and
is found in 3 to 6 lymph nodes near the tumor; or
- may have spread to the submucosa
(layer of tissue next to the mucosa)
of the stomach wall and is found in 7 or more lymph nodes near the
tumor.
Stage
III
Stage III gastric cancer is
divided into stage IIIA, stage IIIB, and stage IIIC, depending on where
the cancer has
spread.
- Stage IIIA:
Cancer has spread to:
- the serosa
(outermost) layer of the stomach
wall and is found in 1 or 2 lymph
nodes near the tumor;
or
- the subserosa
(layer of tissue
next to the serosa) of the stomach wall and is found in 3 to 6 lymph
nodes near the tumor; or
- the muscle layer of the stomach wall and is found in 7
or more lymph nodes near the tumor.
- Stage IIIB:
Cancer has spread to:
- nearby organs
such as the spleen,
transverse colon, liver, diaphragm, pancreas, kidney, adrenal gland, or small intestine, and may be
found in 1 or 2 lymph nodes
near the tumor; or
- the serosa
(outermost layer) of the stomach
wall and is found in 3 to 6 lymph nodes near the tumor; or
- the subserosa
(layer of tissue
next to the serosa) of the stomach wall and is found in 7 or more lymph
nodes near the tumor.
- Stage IIIC:
Cancer has spread to:
- nearby organs
such as the spleen,
transverse colon, liver, diaphragm, pancreas, kidney, adrenal gland, or small intestine, and may be
found in 3 or more lymph nodes
near the tumor; or
- the serosa
(outermost layer) of the stomach
wall and is found in 7 or more lymph nodes near the tumor.
Stage
IV
In stage IV, cancer has spread to distant
parts of the body.
Recurrent Gastric Cancer
Recurrent gastric cancer is cancer that has recurred (come back) after
it has been treated. The cancer may come back in the stomach or in other parts of
the body such as the liver
or lymph nodes.
Treatment Option Overview
Key Points
- There are different types of treatment for patients with
gastric cancer.
- Five types of standard treatment are used:
- Surgery
- Chemotherapy
- Radiation therapy
- Chemoradiation
- Targeted therapy
- New types of treatment are being tested in clinical trials.
- Patients may want to think about taking part in a clinical
trial.
- Patients can enter clinical trials before, during, or after
starting their cancer treatment.
- Follow-up tests may be needed.
There
are different types of treatment for patients with gastric cancer.
Different types of
treatments are available for patients with gastric
cancer. Some treatments are standard
(the currently used treatment), and some are being tested in clinical trials. A treatment
clinical trial is a research
study meant to help improve current treatments or obtain
information on new treatments for patients with cancer. When clinical trials
show that a new treatment is better than the standard treatment, the
new treatment may become the standard treatment. Patients may want to
think about taking part in a clinical trial. Some clinical trials are
open only to patients who have not started treatment.
Five
types of standard treatment are used:
Surgery
Surgery is a common
treatment of all stages
of gastric cancer. The following types of surgery may be used:
- Subtotal gastrectomy:
Removal of the part of the stomach
that contains cancer, nearby lymph
nodes, and parts of other tissues
and organs near the
tumor. The spleen may be removed. The
spleen is an organ in the upper abdomen
that filters the blood
and removes old blood cells.
- Total gastrectomy: Removal of the entire stomach, nearby
lymph nodes, and parts of the esophagus,
small intestine,
and other tissues near the tumor. The spleen may be removed. The
esophagus is connected to the small intestine so the patient can
continue to eat and swallow.
If the tumor is
blocking the stomach but the cancer cannot be completely removed by
standard surgery, the following procedures may be used:
- Endoluminal stent
placement: A procedure to insert a stent (a thin, expandable tube) in
order to keep a passage (such as arteries
or the esophagus) open. For tumors blocking the passage into or out of
the stomach, surgery may be done to place a stent from the esophagus to
the stomach or from the stomach to the small intestine to allow the
patient to eat normally.
- Endoluminal laser
therapy: A procedure in which an endoscope (a thin, lighted
tube) with a laser
attached is inserted into the body. A laser is an intense beam of light
that can be used as a knife.
- Gastrojejunostomy: Surgery to remove the part of the
stomach with cancer that is blocking the opening into the small
intestine. The stomach is connected to the jejunum
(a part of the small intestine) to allow food and medicine to pass from the
stomach into the small intestine.
Chemotherapy
Chemotherapy is a cancer
treatment that uses drugs
to stop the growth of cancer cells, either by killing the cells or by
stopping them from dividing. When chemotherapy is taken by mouth or injected into a vein or muscle, the drugs
enter the bloodstream and can reach cancer cells throughout the body (systemic chemotherapy). When
chemotherapy is placed directly into the cerebrospinal
fluid, an organ, or a body cavity
such as the abdomen, the drugs mainly affect cancer cells in those
areas (regional chemotherapy).
The way the chemotherapy is given depends on the type and stage of the
cancer being treated.
See Drugs Approved for
Stomach (Gastric) Cancer for more information.
Radiation
therapy
Radiation therapy is a
cancer treatment that uses high-energy x-rays
or other types of radiation
to kill cancer cells or keep them from growing. There are two types of
radiation therapy:
- External radiation
therapy uses a machine outside the body to send radiation
toward the cancer.
- Internal radiation
therapy uses a radioactive
substance sealed in needles, seeds,
wires, or catheters
that are placed directly into or near the cancer.
The way the radiation
therapy is given depends on the type and stage of the cancer being
treated. External radiation therapy is used to treat gastric cancer.
Chemoradiation
Chemoradiation therapy
combines chemotherapy and radiation therapy to increase the effects of
both. Chemoradiation given after surgery, to lower the risk that the
cancer will come back, is called adjuvant
therapy. Chemoradiation given before surgery, to shrink
the tumor (neoadjuvant therapy),
is being studied.
Targeted
therapy
Targeted therapy is a type
of treatment that uses drugs or other substances to identify and attack
specific cancer cells without harming normal cells. Monoclonal antibody therapy is a type of
targeted therapy used in the treatment of gastric cancer.
Monoclonal antibody
therapy uses antibodies
made in the laboratory from a single type of immune system cell. These
antibodies can identify substances on cancer cells or normal substances
that may help cancer cells grow. The antibodies attach to the
substances and kill the cancer cells, block their growth, or keep them
from spreading. Monoclonal antibodies are given by infusion. They may be used
alone or to carry drugs, toxins,
or radioactive material directly to cancer cells. For stage IV gastric cancer and
gastric cancer that has recurred,
monoclonal antibodies, such as trastuzumab
or ramucirumab, may
be given. Trastuzumab blocks the effect of the growth factor protein HER2, which sends growth
signals to gastric cancer cells. Ramucirumab blocks the effect of the
protein VEGF and
may prevent the growth of new blood
vessels that tumors need to grow.
See Drugs Approved for
Stomach (Gastric) Cancer for more information.
New
types of treatment are being tested in clinical trials.
Information about
clinical trials is available from the NCI website.
Patients
may want to think about taking part in a clinical trial.
For some patients,
taking part in a clinical trial
may be the best treatment choice. Clinical trials are part of the
cancer research process. Clinical trials are done to find out if new
cancer treatments are safe and effective or better than the standard treatment.
Many of today's
standard treatments for cancer are based on earlier clinical trials.
Patients who take part in a clinical trial may receive the standard
treatment or be among the first to receive a new treatment.
Patients who take
part in clinical trials also help improve the way cancer will be
treated in the future. Even when clinical trials do not lead to
effective new treatments, they often answer important questions and
help move research forward.
Patients
can enter clinical trials before, during, or after starting their
cancer treatment.
Some clinical trials
only include patients who have not yet received treatment. Other trials
test treatments for patients whose cancer has not gotten better. There
are also clinical trials that test new ways to stop cancer from recurring (coming back) or
reduce the side effects
of cancer treatment.
Clinical trials are
taking place in many parts of the country. See the Treatment Options
section that follows for links to current treatment clinical trials.
These have been retrieved from NCI's
listing of clinical trials.
Follow-up
tests may be needed.
Some of the tests
that were done to diagnose
the cancer or to find out the stage
of the cancer may be repeated. Some tests will be repeated in order to
see how well the treatment is working. Decisions about whether to
continue, change, or stop treatment may be based on the results of
these tests.
Some of the tests
will continue to be done from time to time after treatment has ended.
The results of these tests can show if your condition
has changed or if the cancer has recurred
(come back). These tests are sometimes called follow-up tests or check-ups.
Treatment Options by Stage
Stage 0 (Carcinoma in Situ)
Treatment of stage 0 is usually surgery (total or subtotal gastrectomy).
Check the
list of NCI-supported cancer clinical trials that are now accepting
patients with stage 0 gastric cancer. For more specific results, refine
the search by using other search features, such as the location of the
trial, the type of treatment, or the name of the drug. Talk with your
doctor about clinical trials that may be right for you. General
information about clinical trials is available from the NCI website.
Stage I Gastric Cancer
Treatment of stage I gastric cancer may
include the following:
- Surgery
(total or subtotal gastrectomy).
- Surgery (total or subtotal gastrectomy) followed by chemoradiation therapy.
- A clinical trial
of chemoradiation therapy given before surgery.
Check the
list of NCI-supported cancer clinical trials that are now accepting
patients with stage I gastric cancer. For more specific results, refine
the search by using other search features, such as the location of the
trial, the type of treatment, or the name of the drug. Talk with your
doctor about clinical trials that may be right for you. General
information about clinical trials is available from the NCI website.
Stage II Gastric Cancer
Treatment of stage II gastric cancer may
include the following:
- Surgery
(total or subtotal gastrectomy).
- Surgery (total or subtotal gastrectomy) followed by chemoradiation therapy or chemotherapy.
- Chemotherapy given before and after surgery.
- A clinical trial
of surgery followed by chemoradiation therapy testing new anticancer drugs.
- A clinical trial of chemoradiation therapy given before
surgery.
Check the
list of NCI-supported cancer clinical trials that are now accepting
patients with stage II gastric cancer. For more specific results,
refine the search by using other search features, such as the location
of the trial, the type of treatment, or the name of the drug. Talk with
your doctor about clinical trials that may be right for you. General
information about clinical trials is available from the NCI website.
Stage III Gastric Cancer
Treatment of stage III gastric cancer may
include the following:
- Surgery
(total gastrectomy).
- Surgery followed by chemoradiation
therapy or chemotherapy.
- Chemotherapy given before and after surgery.
- A clinical trial
of surgery followed by chemoradiation therapy testing new anticancer drugs.
- A clinical trial of chemoradiation therapy given before
surgery.
Check the
list of NCI-supported cancer clinical trials that are now accepting
patients with stage III gastric cancer. For more specific results,
refine the search by using other search features, such as the location
of the trial, the type of treatment, or the name of the drug. Talk with
your doctor about clinical trials that may be right for you. General
information about clinical trials is available from the NCI website.
Stage IV and Recurrent Gastric Cancer
Treatment of stage IV or recurrent gastric cancer may include
the following:
- Chemotherapy
as palliative therapy
to relieve symptoms
and improve the quality of life.
- Targeted therapy
with a monoclonal antibody
with or without chemotherapy.
- Endoluminal laser
therapy or endoluminal stent
placement to relieve a blockage in the stomach,
or gastrojejunostomy to bypass the blockage.
- Radiation therapy
as palliative therapy to stop bleeding, relieve pain, or shrink a tumor that is blocking the
stomach.
- Surgery
as palliative therapy to stop bleeding or shrink a tumor that is
blocking the stomach.
- A clinical trial
of new combinations of chemotherapy as palliative therapy to relieve
symptoms and improve the quality of life.
-NIH
