Stomach Cancer Diagnosis

Stomach cancer often does not have symptoms until it has spread to other parts of the body, or the symptoms are mistaken for other conditions. This means it can be challenging to diagnose, especially early on.

However, it is important to catch and diagnose stomach cancer as soon and as accurately as possible. This helps increase your odds for successful treatment and lowers the chance of side effects.

If you have symptoms that may signal stomach cancer, your doctor will examine you and ask questions about your health and lifestyle, including smoking and drinking habits, and your family medical history. One or more of the following tests may be used to find out if you have stomach cancer, if it has spread or if treatment is working.

Blood tests: No one blood test can definitely diagnose you with stomach cancer. However, your doctor can run blood tests that give important indicators about your health and may indicate whether other organ systems are being affected by cancer. Additional tests, like a complete blood count (CBC) test, can be used to check for anemia. This could be a sign that the cancer is bleeding into the stomach.

Your doctor can also test your blood for cancer antigen 125 (CA-125) and carcinoembryonic antigen (CEA). These proteins, or tumor markers, are sometimes produced by cancerous tumors, and they can be detected in the blood. These tests can be done to determine if your cancer is growing or responding to treatment. However, not all cancers produce CEA, and high CEA levels do not necessarily mean you have stomach cancer.

Fecal occult blood test: Stool is examined for traces of blood that are not visible to the naked eye. This may indicate that cancer is bleeding into the stomach. 

Upper endoscopy: A small flexible tube with a camera at the end called an endoscope is inserted through the mouth into the esophagus and stomach. This allows your doctor to look for signs of cancer. The endoscope may also be equipped with a tool to remove samples of suspicious tissue (biopsy).

Biopsy: A biopsy is the removal of tissue to examine under a microscope to determine if cancer cells are present. For stomach cancer, biopsies are usually performed during an endoscopy.

Endoscopic ultrasound: Doctors insert an endoscope equipped with a small ultrasound device into the stomach. The ultrasound uses sound waves to produce an image on a video screen, allowing your doctor to see how deeply the cancer has invaded the stomach walls, or check for pre-cancerous changes.

Imaging tests allow your doctor to see the inside of your abdomen and stomach. They may be used to confirm the location of a cancerous stomach tumor, and they can also show whether the cancer has spread to nearby organs. Common imaging tests include:

• CT or CAT (computed axial tomography) scans
• PET (positron emission tomography) scans
• MRI (magnetic resonance imaging) scans
• X-rays (Also called an upper GI (gastrointestinal) series)

Staging laparoscopy: A staging laparoscopy is a minimally invasive procedure used to determine how far the disease has progressed. While the patient is under general anesthesia, doctors will insert a thin tube equipped with a camera into the abdominal cavity. They can then carefully examine the surfaces of the abdominal organs for signs that cancer has spread from the stomach. They may also 'wash' the abdominal cavity with a saline solution. This is called 'peritoneum washing.' The solution is removed and can be checked for the presence of cancer cells. This allows your doctor to catch cancer that is not yet visible on other imaging tests.

Behavioral and lifestyle changes can help prevent stomach cancer. Visit our prevention and screening section to learn how to manage your risk.

In rare cases, stomach cancer can be passed down from one generation to the next. Genetic counseling may be right for you. Visit our genetic testing page to learn more.