Physicians will use a variety of diagnostic methods to determine if cancer is present in an individual. Initially, the patient’s medical history will be compiled for possible contributing factors. A thorough physical examination will be completed with particular focus on the abdomen and lymph nodes.

A number of tests may be administered to help identify the location of tumors and diagnose or rule out cancer. If cancer is detected, these tests can determine the type of cancer as well as the stage (spread) of the cancer. Tests and evaluations used to detect stomach cancer can include:

• Blood tests (e.g., complete blood counts). These tests are taken to determine chemical or hormonal imbalances that may indicate cancer cells in the tissues or organs, or anemia that indicates bleeding from the tumore.
  
  
• Fecal occult blood test (FOBT). A sample of stool (solid waste) is examined chemically for the presence of trace amounts of blood. Simple home FOBT can be conducted by the patient as well. There is a significant incidence of false positives and negatives with FOBT.
  
  
• X-ray. The use of x-rays to create images of the body. X-rays and scans can help to detect if there is metastasis (cancer spread) to the bones or other organs.
  
  
• Barium x-ray. A series of x-rays of the esophagus and stomach are taken after the patient drinks a liquid containing barium, a chalky compound that coats the GI tract and makes it visible on x-ray scans.
  
  
• Computed axial tomography (CAT scan). Cross-sectional images are taken of the body using specialized x-rays and a computer analysis. Contrast medium (dye) may be used to help locate tumors and abnormalities in the body.

• Magnetic resonance imaging (MRI). Radio wave technology is used to create detailed images of internal organs and tissues in the body.
  
  
• Positron emission tomography (PET) scan. A minimally radioactive sugar is injected into the bloodstream and is rapidly absorbed by the cancer cells, making them detectable by forming hot spots on an image. PET scan can be used to determine the spread of cancer.
  
  
• Bone scan. Radioactive material injected into the bloodstream collects in the bones, and images are taken by scanner. The images detect cancer cells in the bones.
  
  
• Upper endoscopy. A thin lighted tube called an endoscope is guided down the throat and used to check for abnormalities in the esophagus, stomach and duodenum.  The procedure is usually performed with the patient sedated.
  
  
• Endoscopic ultrasound (EUS). An endoscope is used with an ultrasound device. This device is passed through the nose or throat into the stomach, where sound waves are sent to the stomach and images of stomach tumors are produced. This ultrasound is effective in detecting small tumors that may not appear on other imaging tests.
  
  
• Laparoscopy. A thin, lighted instrument is attached to a tiny television camera and inserted into the abdomen through a small incision. Laparoscopy can detect tumors and any metastasis to the surrounding tissue as well.
  
  
• Biopsy. Samples from suspected tissue can be taken during laparoscopy, endoscopy, needle biopsy or surgery. A pathologist views the cells under a microscope to determine the presence of cancer.
  
  
• Genetic testing. DNA is analyzed for genetic alterations that can indicate a predisposition for cancer as well as potential prognosis for survival.