How is the disease diagnosed?

Usually, a person sees a healthcare provider because of a symptom such as weight loss and nausea. The provider will take an in-depth history, which includes a nutritional assessment. The first test may be an x-ray of the stomach called an upper gastrointestinal exam, or upper GI. Depending on the results of the upper GI, the next part of the evaluation will be a flexible gastroscopy in which a tiny tube with a light is passed into the stomach. This allows the physician to look at the walls of the stomach. If any of the tissue looks unusual, a biopsy will be done to remove a piece to determine if it is cancer.

If cancer is confirmed, other tests will be done to determine the extent of the disease. These tests include CT scans and other specialized x-rays. Tumor markers, or chemical markers produced by tumors, are not useful in diagnosing early stage stomach cancer but may be useful to track the cancer after surgery.