Stomach Cancer Diagnosis

A stomach cancer diagnosis often comes in the later stages of the disease, because early stomach cancer often displays no obvious symptoms. If you go to your healthcare provider with stomach pain or other possible stomach cancer symptoms, the provider will take your medical history, asking questions about your risk factors, the symptoms you’re experiencing and your current health.

The provider will also do a physical exam, including feeling your abdomen for abnormal changes. Possible lab tests when looking for signs of stomach cancer include a complete blood count (CBC) to look for anemia, and a fecal occult blood test to look for blood in your stool.


The main test used to make a stomach cancer diagnosis is an upper endoscopy (also called an “esophagogastroduodenoscopy” or “EGD”). An endoscope is a thin, flexible tube with a light on the end. During an EGD, the doctor passes the endoscope down your throat to look at the lining of your esophagus, stomach and upper small intestine.

If the doctor sees an abnormal area, he can pass an instrument through the endoscope to take a biopsy (tissue sample). A pathologist will then look at the tissue samples under a microscope to see if they contain cancer.

Other Tests

Your healthcare provider may also perform imaging tests to help find out if a suspicious area is cancerous, to find out how far a cancer has spread and to help determine the effectiveness of treatment. Possible tests include:

  • An upper gastrointestinal (GI) series uses X-rays to look at the esophagus, stomach and part of the small intestine. Before this test, you drink a barium solution that coats the lining of these organs. The barium coating causes an outline of any abnormalities to appear on the X-rays.
  • An endoscopic ultrasound is an ultrasound test done using an endoscope with a transducer. During a standard ultrasound, a transducer placed on the skin emits sound waves and detects echoes as they bounce off internal organs. During an endoscopic ultrasound, the doctor uses an endoscope with a small transducer on its tip. Passing the endoscope down your throat and into the stomach lets the transducer rest directly on the wall of the stomach. The doctor can look at the layers of the stomach wall and nearby lymph nodes.
  • Magnetic resonance imaging (MRI) scan or computed tomography (CT or CAT) scans are sometimes used, as well. According to the American Cancer Society, most doctors prefer CT scans to look at the stomach, but sometimes an MRI may provide more information.

Two other tests your doctor might do after making a stomach cancer diagnosis are:

  • Positron emission tomography (PET) scan: This test uses radioactive glucose to highlight cancer cells using a special camera, and is useful if the cancer might have spread but the doctor doesn’t know where.
  • Laparoscopy: You usually receive this test before surgery to confirm that the cancer is only in the stomach and can be completely removed with surgery. The doctor inserts a laparoscope (a thin, flexible tube) through a small incision in your side. The small camera on the end of the laparoscope sends pictures of the inside of the abdomen to a TV screen.


American Cancer Society. (2010). Stomach cancer. Retrieved February 7, 2011, from

Mayo Clinic. (2009). Stomach cancer: Tests and diagnosis. Retrieved February 7, 2011, from

National Cancer Institute. (n.d.). Stomach (gastric) cancer. Retrieved February 7, 2011, from