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Stomach Cancer Detection & Diagnosis

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There is currently no standard screening test for stomach cancer for people at average risk. Because of this, it’s important to speak with your doctor if you experience persistent or unusual gastrointestinal symptoms, such as ongoing indigestion, abdominal discomfort, nausea, or unexplained weight loss. Stomach cancer that is not detected until it reaches a more advanced stage can be more difficult to treat.

Your doctor may recommend that you see a gastroenterologist for further testing if initial tests show that cancer may be present.

Diagnostic Tests for Stomach Cancer

Diagnosis typically begins with a review of your medical history, symptoms, and potential risk factors. Your doctor will perform a physical exam and may check for abdominal tenderness, swelling, or other abnormalities. They will also perform other tests to gather as much information as possible before selecting the treatments that will be most effective.

Upper Endoscopy and Stomach Biopsy

An upper endoscopy is the most common procedure used to look inside the stomach. During this test, a thin, flexible tube with a light and a camera is passed through the mouth and into the stomach to examine the lining for abnormal areas. If suspicious tissue is found, the physician can take biopsy tissue samples during the procedure.

A biopsy is the only way to confirm a stomach cancer diagnosis. The collected tissue is examined under a microscope by a pathologist to determine whether cancer is present and, if so, what type of stomach cancer it is.

Imaging Tests

If cancer is suspected or confirmed, imaging tests may be used to determine the extent of the disease. These tests help see how large the tumor is and whether it’s spread.

  • CT scan - Provides detailed cross-sectional images of the soft tissues in the body. It can show the stomach fairly clearly and often can confirm the location of a cancer.
  • Endoscopic ultrasound - Your doctor passes a thin, lighted tube (endoscope) down your throat, through your stomach, and into the first part of the small intestine. This internal view of the pancreas and bile ducts provides a more accurate picture than an external ultrasound can for this area of the body. Biopsy samples can also be taken during this procedure.
  • PET/CT - This test will determine if the cancer has spread beyond the stomach, even if a tumor is not yet detectable in another area of the body.

Biomarker & Molecular Testing

Once stomach cancer is diagnosed, additional laboratory testing may be performed on the tumor tissue to look for specific biomarkers. These can include HER2 status, PD-L1 expression, microsatellite instability (MSI), and other molecular features.

This information can help determine whether targeted therapy or immunotherapy is an appropriate treatment option.

What Happens Next?

After diagnostic testing is complete, additional evaluations may be performed to determine the stage of the cancer. Staging provides critical information about how far the disease has spread and helps your oncology team develop a personalized treatment plan.

CTA