Stomach Cancer

Every year 13,000 men and 8,000 women in the United States are diagnosed with stomach cancer, also called gastric cancer. The cancer usually begins in the cells of the inner layers of the stomach and sometimes spread deeply into the stomach wall. Stomach cancer mostly affects the elderly — two-thirds of those who have it are over the age of 65. It can be difficult to diagnose in its early stages, so it is often diagnosed late.

Cancer of the stomach, also called gastric cancer, can be difficult to detect before it has spread. Often, there are no symptoms in the early stages. When symptoms do occur, they may include the following:

  • Indigestion or 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
  • Bleeding, including vomiting blood or having blood in the stool

To find the cause of symptoms, your doctor will take your medical history, perform a physical exam and recommend laboratory studies. You also may have one or all of the following exams:

  • Fecal Occult Blood Test (FOBT) — FOBT is 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 your 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 — These are X-rays of the esophagus and stomach (the upper gastrointestinal, or GI, tract). X-rays are taken after you drink a barium solution, a thick, chalky liquid. This test is sometimes called a barium swallow. Barium outlines the stomach on the X-rays, helping your doctor find tumors or other abnormal areas.

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Surgery, called gastrectomy, is the most common treatment for stomach cancer. The surgeon removes part or all of the stomach, as well as some of the tissue around the stomach.

After a partial gastrectomy, your doctor connects the remaining part of your stomach to the esophagus or the small intestine. After a total gastrectomy, your doctor connects the esophagus directly to your small intestine.

Because cancer can spread through the lymphatic system, lymph nodes near the tumor are often removed during surgery so a pathologist can check them for cancer cells.

Radiation Therapy

Radiation therapy is the use of X-rays or other high-energy rays to kill cancer cells and shrink tumors. Radiation for gastric cancer comes from a machine outside the body, or external radiation therapy. Radiation can be used alone or in addition to surgery and chemotherapy.

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Reviewed by health care specialists at UCSF Medical Center.