Diagnosing Stomach Cancer

NYU Langone specialists at Perlmutter Cancer Center use imaging tests and a biopsy to aid in diagnosing stomach cancer. Also called gastric cancer, it begins when cells in the stomach grow uncontrollably, forming a tumor.

There are five layers of tissue in the stomach. Most cancers begin in the innermost layer, called the mucosa. These are called adenocarcinomas. Other forms are less common. Lymphoma, a cancer of the immune system, is sometimes found in the wall of the stomach. Gastric stromal tumors occur in the muscle layer of the stomach wall. Another type, carcinoid tumors, are cancers of the stomach’s hormone-producing cells.

Experts believe it takes several years for stomach cancer to develop. It’s not usually found early because it has few specific or unique symptoms. When symptoms do occur, they may be vague and resemble those of other conditions.

The symptoms may include indigestion, heartburn, and nausea and vomiting, especially after eating. Bloating may occur after meals. Some people have a sensation of food getting stuck in the chest. Other symptoms may include diarrhea or constipation, loss of appetite, chronic reflux, and unexplained fatigue.

Symptoms of advanced stomach cancer can include vomiting blood, blood in the stool, unexplained weight loss, anemia, weakness, and fatigue.

Upper Endoscopy with Biopsy

When doctors suspect stomach cancer, they may perform an upper endoscopy, which allows them to view the lining of the stomach. During this procedure, a doctor inserts an endoscope—a thin, lighted tube with a tiny camera on the end—into the nose or mouth, through the esophagus, and into the stomach, as well as the first part of the small intestine. The procedure is performed using a sedative.

When the lining of the stomach looks suspicious, your doctor may perform a biopsy. This involves inserting small surgical tools through the endoscope to remove tissue samples to check for signs of cancer. A pathologist, a doctor who studies diseases in a laboratory, examines the biopsy samples to determine whether a person has adenocarcinoma and, if so, how aggressive it is.

Doctors may also test the stomach cells for excessive amounts of a protein called human epidermal growth factor receptor 2 (HER2) on their surface. This protein helps a cancer grow. Sometimes, people with HER2-positive cancer may be candidates for targeted drug therapy.

Endoscopic Ultrasound

If a biopsy indicates that a person has stomach cancer, NYU Langone doctors may perform an endoscopic ultrasound to determine how large the tumor is, how deeply it has grown into the wall of the stomach lining, and whether it has spread to nearby lymph nodes. Lymph nodes are immune system glands located throughout the body that trap bacteria and viruses. Cancer often spreads to the lymph nodes first.

Ultrasound uses sound waves to create images of the body. During an endoscopic ultrasound, the person is given a sedative. Then a doctor threads a specialized endoscope that has an ultrasound probe on the tip through the mouth and into the stomach.

If the ultrasound reveals that lymph nodes are enlarged, the doctor can place a small needle through the endoscope and remove a tissue sample to check for signs of cancer.

CT Scans

Your doctor may use a CT scan, a type of X-ray that creates cross-sectional, three-dimensional pictures of the stomach and nearby organs. A CT scan can reveal whether cancer has spread to any of the abdominal organs, such as the liver.

You may receive a contrast agent or dye to enhance the image. This is taken before the test by mouth or injection. Information from a CT scan can help a doctor determine whether surgery is an option.

PET/CT Scans

After diagnosing stomach cancer, a doctor may order a combination PET and CT scan to determine if the tumor has spread to other organs, such as the liver. The test can also show how active the cancer is.

The combined scan provides a single set of computer-generated, three-dimensional images. The CT portion of the test gives cross-sectional X-ray images of the body; the PET scan detects tumor activity. A PET scan uses a small amount of radioactive glucose, or sugar, injected into a vein. This material collects in cancer tissue and is detected with a special camera.

After treatment, this scan may help a doctor determine whether a tumor or the stomach still contains cancer or whether only scar tissue remains.