Gastric Cancer
On this page:
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 colon).
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.
Age, diet, and stomach disease can affect the risk of developing gastric
cancer.
- Helicobacter pylori infection of the stomach.
- Chronic gastritis (inflammation of the stomach).
- Older age.
- Being male.
- A diet high in salted, smoked, or poorly preserved foods and low in fruits and
vegetables.
- Pernicious anemia.
- Smoking cigarettes.
- Intestinal metaplasia.
- Familial adenomatous polyposis (FAP) or gastric polyps.
- A mother, father, sister, or brother who has had stomach cancer.
Possible signs of gastric cancer include indigestion and stomach discomfort
or pain.
These and other symptoms may be caused by gastric
cancer or by other conditions.
- Indigestion and stomach discomfort.
- A bloated feeling after eating.
- Mild nausea.
- Loss of appetite.
- Heartburn.
- Blood in the stool.
- Vomiting.
- Weight loss (unexplained).
- Stomach pain.
- Jaundice (yellowing of eyes and skin).
- Ascites (build-up of fluid in the abdomen).
- Difficulty swallowing.
A doctor should be consulted if any of these problems
occur.
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 in the organ or tissue that produces it.
- Complete blood count: 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.
- Fecal occult blood test: A test to check stool (solid waste) for blood that can
only be seen with a microscope. Small samples of stool are placed on special
cards and returned to the doctor or laboratory for testing.
- 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.
- 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.
- 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.
Certain factors affect prognosis (chance of recovery) and treatment options.
- The stage and extent 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.
When gastric cancer is found very early, there
is a better chance of recovery. Gastric cancer is often in an advanced stage
when it is diagnosed. At later stages, gastric cancer can be treated but rarely
can be cured. Taking part in one of the clinical trials being done to improve
treatment should be considered.
Return
to top 
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:
- ß-hCG (beta-human chorionic gonadotropin), CA-125, and CEA (carcinoembryonic
antigen) assays: Tests that measure the levels of ß-hCG, CA-125, and CEA
in the blood. These substances are released into the bloodstream from both
cancer cells and normal cells. When found in higher than normal amounts,
they can be a sign of gastric cancer or other conditions.
- Chest x-ray: An x-ray of the organs and bones inside the chest. An x-ray is a
type of energy beam that can go through the body and onto film, making a
picture of areas inside the body.
- Endoscopic ultrasound (EUS): A procedure in which an endoscope (a thin, lighted
tube) is inserted into the body. 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.
- Laparoscopy: A surgical procedure to look at the organs inside the abdomen to
check for signs of disease. Small incisions (cuts) are made in the wall of
the abdomen and a laparoscope (a thin, lighted tube) is inserted into one
of the incisions. Other instruments may be inserted through the same or other
incisions to remove lymph nodes or take tissue samples for biopsy.
- PET scan (positron emission tomography scan): A procedure to find malignant tumor
cells in the body. A small amount of radionuclide 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.
In stage 0, cancer is found only in the inside lining
of the mucosal (innermost) layer of the stomach wall. Stage 0 is also called
carcinoma in situ.
Stage I gastric cancer is divided into stage IA
and stage IB, depending on where the cancer has spread.
- Stage IA: Cancer has spread completely through the mucosal (innermost)
layer of the stomach wall.
- Stage IB: Cancer has spread:
- completely through the mucosal (innermost) layer of the
stomach wall and is found in up to 6 lymph nodes near the tumor; or
- to the muscularis (middle) layer of the stomach wall.
In stage II gastric cancer, cancer has spread:
- completely through the mucosal (innermost) layer of the stomach
wall and is found in 7 to 15 lymph nodes near the tumor; or
- to the muscularis (middle) layer of the stomach wall and is found in up to 6
lymph nodes near the tumor; or
- to the serosal (outermost) layer of the stomach wall but not to lymph nodes or
other organs.
Stage III gastric cancer is divided into stage
IIIA and stage IIIB depending on where the cancer has spread.
- Stage IIIA: Cancer has spread to:
- the muscularis (middle) layer of the stomach wall and is
found in 7 to 15 lymph nodes near the tumor; or
- the serosal (outermost) layer of the stomach wall and is found in 1 to 6 lymph
nodes near the tumor; or
- organs next to the stomach but not to lymph nodes or other parts of the body.
- Stage IIIB: Cancer has spread to the serosal (outermost) layer of
the stomach wall and is found in 7 to 15 lymph nodes near the tumor.
In stage IV, cancer has spread to:
- organs next to the stomach and to at least one lymph node; or
- more than 15 lymph nodes; or
- other parts of the body.
Return
to top
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. Before starting treatment,
patients may want to think about taking part in a clinical trial. 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.
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 opening to 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 opening to the stomach, surgery may be done
to place a stent from the esophagus to the stomach to allow the patient to
eat normally.
- Endoscopic laser surgery: 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.
- Electrocautery: A procedure that uses an electrical current to create heat. This
is sometimes used to remove lesions or control bleeding.
Chemotherapy is a cancer treatment that uses drugs
to stop the growth of cancer cells, either by killing the cells or by stopping
the cells 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 spinal column, an organ, or a body cavity such as the abdomen, the
drugs mainly affect cancer cells in those areas. The way the chemotherapy is
given depends on the type and stage of the cancer being treated.
Radiation therapy is a cancer treatment that uses
high-energy x-rays or other types of radiation to kill cancer cells. 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.
Chemoradiation combines chemotherapy and radiation
therapy to increase the effects of both. Chemoradiation treatment given after
surgery to increase the chances of a cure is called adjuvant therapy. If it
is given before surgery, it is called neoadjuvant therapy.
Other types of treatment are being tested in clinical trials. These include
the following:
Biologic therapy is a treatment that uses the patient’s
immune system to fight cancer. Substances made by the body or made in a laboratory
are used to boost, direct, or restore the body’s natural defenses against cancer.
This type of cancer treatment is also called biotherapy or immunotherapy.
Return
to top
Treatment of stage 0 gastric cancer is usually surgery
(total or subtotal gastrectomy).
Treatment of stage I and stage II 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.
Treatment of stage III gastric cancer may include
the following:
- Surgery (total gastrectomy).
- Surgery followed by chemoradiation therapy.
- A clinical trial of chemoradiation therapy given before surgery.
Treatment of stage IV gastric cancer that has
not spread to distant organs may include the following:
- Surgery (total gastrectomy) followed by chemoradiation therapy.
- A clinical trial of chemoradiation therapy given before surgery.
Treatment of stage IV gastric cancer that has
spread to distant organs may include the following:
- Chemotherapy as palliative therapy to relieve symptoms and improve
the quality of life.
- Endoscopic laser surgery or endoluminal stent placement as palliative therapy
to relieve symptoms and improve the quality of life.
- Radiation therapy as palliative therapy to stop bleeding, relieve pain, or shrink
a tumor that is blocking the opening to the stomach.
- Surgery as palliative therapy to stop bleeding or shrink a tumor that is blocking
the opening to the stomach.
Return
to top
