Upper endoscopy

This is the primary test used to detect stomach cancer. The doctor uses an endoscope, a flexible, narrow tube with a camera and light on the end. This device allows the doctor to examine the lining of the esophagus, stomach and small intestine and look for any irregularities. If the doctor notices an area of abnormal tissue, he will use the endoscope to take a tissue sample for biopsy.

Endoscopic ultrasound (EUS)

For this procedure, the gastroenterologist uses an endoscope with an ultrasound device at the end of the tube. This device sends out high-frequency sound waves to make images of the stomach and allows the doctor to see how deep the tumor has grown into the wall and whether it has invaded the lymph nodes. This technique may be crucial when deciding if a malignant growth can be removed through the endoscope.

Upper gastrointestinal (GI) series

This test is also referred to as the barium swallow. The patient drinks a chalky liquid called barium and undergoes a series of X-rays. The barium covers the inside layer of the esophagus, stomach, and small intestine and clearly outlines it on the X-rays, making it easy for the doctor to identify any abnormalities. This test is done much less commonly since endoscopy is so much more available than years past.

Computed tomography (CT) scan

A computed tomography (CT) scan uses X-rays to produce an image of your body. For a CT scan, you lie flat on a table while a machine rotates around your body and takes X-rays. A special dye may be injected and you may be asked to drink a special fluid in order to make the internal organs stand out. A CT scan reveals the presence of tumors and whether or not the cancer has spread to other parts of your body.

Magnetic resonance imaging (MRI) scan

MRI scans use radio waves and a strong magnet to create clear and detailed images of body parts. Radio waves are absorbed by the body and then released in a certain pattern which is translated by a computer in order to show “slices” of the body. Since motion artifact is problematic for MRI scans and since MRI unusually does not add to the findings on CT, doctors usually only use MRIs for gastric cancer when a CT scan cannot be used.

Positron emission tomography (PET) scan

Doctors use PET scans when they think the cancer might have spread but do not know where. The doctor injects a radioactive substance into a patient’s bloodstream. The substance collects in cancer cells in the patient’s body over the course of about one hour. The doctor then uses a PET Scanner to detect the areas of radioactivity and to find the exact location of cancer.

Laparoscopy

Your doctor may perform a laparoscopy after discovering stomach cancer to evaluate whether the cancer has spread to the lining of the abdominal cavity. A laparoscope is a thin, flexible tube with a camera and light on the end that your doctor passes through an incision in your side and uses to examine the inside of your abdomen.

Complete blood count (CBC)

A CBC measures the levels of a person's blood cells, including red blood cells, white blood cells and platelets. Your doctor may order a CBC to check for anemia (low red blood cells), which can be caused by internal bleeding related to stomach cancer.

Tumor markers

Tumor markers are substances found in higher than normal amounts in a person's blood or urine when they have a specific type of cancer. For stomach cancer, the doctor may have the patient's blood analyzed for CEA, though this test is non-specific and is not sufficient to diagnose stomach cancer.

• Please see Understanding Tumor Markers: CEA for more information

• Please see Understanding Tumor Markers: CA 19-9 for more information

Fecal occult blood test

Your doctor may check your stool for signs of blood. The routine tests for occult blood are limited by their inherent sensitivity and the fact that it takes much more blood loss from the upper gastrointestinal tract compared to a site of bleeding in the colon. Bleeding in the stomach can cause black or bloody stools.

Biopsy

If any of these diagnostic tests indicate that you might have cancer, your doctor will conduct a biopsy to be certain. Your doctor will remove a tissue sample and have a pathologist examine it under a microscope to determine if it contains cancer cells. A biopsy is the only way to be certain of a cancer diagnosis. Your doctor will most likely take a biopsy sample while performing an endoscopy. If your doctor notices an abnormality during the procedure, he will pass a special tool through the endoscope and use it to take a tissue sample.