About Gastric Cancer

Symptoms and Diagnosis
stomach cancer

What is Gastric Cancer?

Gastric (stomach) cancer tends to develop slowly over many years. Before cancer develops, pre-cancerous changes often occur in the lining of the stomach but rarely cause symptoms and can go undetected.

There is much cause for hope if gastric cancer is found early, however the outlook is poor if discovered at an advanced stage. That’s why Gastric Cancer Foundation is dedicated to advancing gastric cancer research. It’s only through long-term research that we will be able to find a cure.

Gastric Cancer Symptoms

When gastric cancer causes symptoms, they can be similar to other health problems, such as an ulcer or infection. Anyone with these symptoms should talk to a doctor so problems can be diagnosed and treated as early as possible.

As gastric cancer grows, the most common symptoms are:

Discomfort or pain in the stomach area

Difficulty swallowing

Nausea and vomiting

Weight loss

Feeling full or bloated after a small meal

Vomiting blood or having blood in the stool

Gastric Cancer Diagnosis

If your doctor suspects you have gastric cancer, you will be asked about your personal and family health history and may have blood or other lab tests. Your doctor may refer you to a gastroenterologist, a doctor whose specialty is diagnosing and treating digestive problems.

Diagnostic tests include:

Physical exam: Your doctor feels your abdomen for fluid, swelling, or other changes and check for swollen lymph nodes.

Endoscopy: Your doctor looks inside your stomach using a thin, lighted tube (endoscope). Your doctor first numbs your throat with an anesthetic. You also may receive medicine to help you relax. The tube is passed through your mouth and esophagus to the stomach.

Biopsy: Your doctor can use the endoscope to remove tissue from the stomach. A pathologist checks the tissue under a microscope for cancer cells. A biopsy is the only sure way to know if cancer cells are present.

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Want to Know More about Gastric Cancer?

Learn how gastric cancer spreads, how it develops, and the multiple stages of gastric cancer. Find out about potential risk factors as well.

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Gastric Cancer Treatments

Partial (subtotal) gastrectomy for tumors at the lower part of the stomach

A surgeon removes the lower part of the stomach with the cancer. The surgeon attaches the remaining part of the stomach to the intestine. Nearby lymph nodes and other tissues may also be removed.

● What kind of surgery do you recommend for me? Why?
● Will you remove lymph nodes? Will you remove other tissue? Why?
● How will I feel after surgery?
● Will I need a special diet?
● If I have pain, how will you control it?
● How long will I be in the hospital?
● Am I likely to have eating problems?
● Will I have any long-term side effects?
● What is the plan for pain relief?

Total gastrectomy for tumors at the upper part of the stomach

A surgeon removes the entire stomach, nearby lymph nodes, parts of the esophagus and small intestine, and other tissues near the tumor. Rarely, the spleen may also be removed. The surgeon then connects the esophagus directly to the small intestine.

The type of surgery for depends mainly on where the cancer is located. A surgeon may remove the whole gastric or only the part that has the cancer.
Healing after surgery is different for everyone. You may have pain for the first few days and be in the hospital for a week or longer. Medicine can help control your pain. After surgery, your doctor can adjust the plan if you need more pain relief.
Many people who have stomach surgery feel tired or weak for a while. Your health care team will watch for signs of bleeding, infection, or other problems that may require treatment.
The surgery can also cause constipation or diarrhea. These symptoms usually can be controlled with diet changes and medicine. Visit the Nutrition section for information about eating after surgery.
You may want to ask your doctor these questions before having surgery:
● What kind of surgery do you recommend for me? Why?
● Will you remove lymph nodes? Will you remove other tissue? Why?
● How will I feel after surgery?
● Will I need a special diet?
● If I have pain, how will you control it?
● How long will I be in the hospital?
● Am I likely to have eating problems?
● Will I have any long-term side effects?
● What is the plan for pain relief?


Most people with gastric cancer get chemotherapy, which uses drugs to kill cancer cells. It may be given before or after surgery. After a surgery, radiation therapy may be given along with chemotherapy. You may receive chemotherapy in an outpatient part of the hospital, at the doctor’s office, or at home. Some people need to stay in the hospital during treatment.

Chemotherapy drugs that treat gastric cancer are either given through a vein (intravenous) or as pills. You’ll probably receive a combination of drugs. The side effects depend mainly on which drugs are given and how much. Chemotherapy kills fast-growing cancer cells, but the drugs can also harm normal cells that divide rapidly:
● Blood cells: When drugs lower the levels of healthy blood cells, you’re more likely to get infections, bruise or bleed easily, and feel very weak and tired. Your health care team will check for low levels of blood cells. If your levels are low, your health care team may stop the chemotherapy for a while or reduce the dose of the drug. There are also medicines that can help your body make new blood cells.
● Cells in hair roots: Chemotherapy may cause hair loss. If you lose your hair, it will grow back after treatment, but the color and texture may be changed.
● Cells that line the digestive tract: Chemotherapy can cause poor appetite, nausea and vomiting, diarrhea, or mouth and lip sores. Your health care team can give you medicines and suggest other ways to help with these problems, which usually go away when treatment ends.
Some drugs used for gastric cancer also may cause a skin rash, hearing loss, and tingling or numbness in your hands and feet. Your health care team can suggest ways to control many of these side effects. You may want to read the NCI booklet Chemotherapy and You.
You may want to ask your doctor these questions before having chemotherapy:
● Why do I need this treatment?
● Which drug or drugs will I have?
● How do the drugs work?
● When will treatment start? When will it end?
● Will I have any long-term side effects?

Radiation Therapy

Radiation therapy (also called radiotherapy) uses high-energy rays to kill cancer cells. It affects cells in the only part of the body being treated. Radiation therapy is usually given with chemotherapy to treat gastric cancer. The radiation comes from a large machine outside the body. You’ll go to a hospital or clinic for treatment. Treatments are usually 5 days a week for several weeks.

Radiation therapy side effects depend mainly on the dose and type of radiation. External radiation therapy to the chest and abdomen may cause a sore throat, pain similar to heartburn, or pain in the stomach or the intestine. You may have nausea and diarrhea. Your health care team can give you medicines to prevent or control these problems.
It’s common for the skin in the treated area to become red, dry, tender, and itchy. You’re 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 active, unless it leads to pain or other problems.
Although the side effects of radiation therapy can be distressing, your doctor can usually treat or control them. Also, side effects usually go away after treatment ends.
You may find it helpful to read the NCI booklet Radiation Therapy and You.
You may want to ask your doctor these questions before having radiation therapy:
● Why do I need this treatment?
● When will the treatments begin? When will they end?
● How will I feel during treatment?
● How will we know if the radiation treatment is working?
● Will I have any long-term side effects?


Immunotherapy treatments help the immune system recognize cancer cells and destroy them. One approach commonly used in gastric cancer involves inhibiting “checkpoints, ” which are proteins that normally help cancer cells hide from the immune system. A drug that blocks the checkpoint PD-1 is approved by the FDA to treat patients with advanced gastric cancer who have previously received chemotherapy. There are several other immunotherapy treatments in clinical trials for gastric cancer, including personalized cell-based therapies made from patients’ own immune cells. Ask your oncologist if any marketed or experimental immunotherapies might be good options for you.

Targeted Therapies

Targeted therapies are drugs that destroy cancer cells by homing in on genetic mutations or other abnormalities in tumors. For example, about 20 percent of gastric tumors have excess amounts of HER2, a protein that promotes cancer growth. These tumors can be treated with a HER2-targeting drug, given along with chemotherapy. Some stomach tumors have a genetic abnormality called microsatellite instability high (MSI-high) or mismatch repair deficient, which means the cancer cells are unable to repair their own DNA. Patients whose tumors test positive for MSI-high may be treated with PD-1 blockers, which have been shown to be effective in this patient population. There are several other targeted treatments being tested in clinical trials for gastric cancer.

Supportive Care

Supportive care is treatment to control pain and other symptoms, to relieve the side effects of therapy, and to help you cope with the feelings that a diagnosis of cancer can bring. You may receive supportive care to prevent or control these problems and to improve your comfort and quality of life during treatment.

Gastric cancer and its treatment can lead to other health problems. You can have supportive care before, during, and after cancer treatment. Find more information about supportive care on NCI’s Website and from NCI’s Cancer Information Service at 1-800-4-CANCER and at LiveHelp.

Cancer and its treatments may cause pain. Your health care team or a pain control specialist can suggest ways to relieve or reduce pain. Radiation therapy and pain medicine may help. More information about pain control can be found in the NCI booklet Pain Control.

Stent and Laser Therapy

People with advanced gastric cancer may develop a tumor that blocks the passage of food through the digestive tract, which may include one or more of the following treatment options:
● Stent: A doctor uses an endoscope to place a stent (a tube made of metal mesh or plastic) in your intestine. Food and liquid can pass through the center of the tube.
● Radiation therapy: Radiation therapy may help shrink the tumor that is blocking the intestine.
● Laser therapy: A laser is a concentrated beam of intense light that kills tissue with heat. The doctor uses an endoscope to place the laser in your digestive tract. The laser destroys the cancer cells blocking the digestive tract.

Clinical Trials

Clinical trials are research studies that involve people. They are the final step in a long process that begins with research in a lab. Most treatments we use today are the results of past clinical trials.

Cancer clinical trials are designed to test new ways to:

• Treat cancer
• Find and diagnose cancer
• Prevent cancer
• Manage symptoms of cancer or side effects from its treatment

Any time you or a loved one needs treatment for cancer, clinical trials are an option to think about. Trials are available for all stages of cancer. It is a myth that they are only for people who have advanced cancer that is not responding to treatment.

Every trial has a person in charge, usually a doctor, who is called the principal investigator. The principal investigator prepares a plan for the trial, called a protocol. The protocol explains what will be done during the trial. It also contains information that helps the doctor decide if this treatment is right for you. The protocol includes information about:

• The reason for doing the trial
• Who can join the trial (called “eligibility requirements”)
• How many people are needed for the trial
• Any drugs that will be given, how they will be given, the dose, and how often
• What medical tests will be done and how often
• What types of information will be collected about the people taking part

Why Are Clinical Trials Important?
Clinical trials are key to developing new methods to prevent, detect, and treat cancer. It is through clinical trials that researchers can determine whether new treatments are safe and effective and work better than current treatments. When you take part in a clinical trial, you add to our knowledge about cancer and help improve cancer care.

* Text courtesy of the National Cancer Institute.

Be part of research for treatment. Use our clinical trial navigator to find a clinical trial and enroll in the Gastric Cancer Registry.

We thank the National Cancer Institute for providing the preceding educational content. To view the National Cancer Institute’s complete brochure “What You Need to Know About Stomach Cancer” or to order a free copy, click here.