Diagnosis of esophageal cancer involves a medical history (including information about symptoms [especially difficulty swallowing and weight loss], existing medical conditions [e.g., GERD], and alcohol and tobacco use), physical examination, and medical tests.
Because esophageal cancer tends to spread first to the lymph nodes, physical examination includes palpating (i.e., feeling with the fingers) the lymph nodes to check for enlargement. If the physician suspects lymph node involvement, a needle aspiration (i.e., removal of cells for microscopic evaluation) or biopsy may be performed.
Blood tests may include a complete blood count (CBC) and liver function tests. CBC is used to detect anemia and liver function tests are used to detect liver metastasis and abnormalities caused by a high intake of alcohol.
Imaging tests used to diagnose esophageal cancer include a chest x-ray and a double-contrast barium swallow. In double-contrast barium swallow, the patient drinks a solution that contains barium, which is a dense liquid that appears white on x-rays. Then, air is blown into the esophagus to help the liquid coat the wall of the organ more thoroughly. Esophageal tumors cause the barium to coat the esophagus unevenly, which shows up on x-ray.
Imaging tests used to determine the extent of the disease and to detect metastasis include the following:
- Bone scan (to detect bone metastasis)
- Bronchoscopy (to determine if cancer has invaded the trachea [windpipe] or bronchi [tubes leading from the trachea to the lungs]; performed under sedation)
- CT scan
- Endoscopic ultrasound (to determine the size of the tumor and the extent of spread into nearby tissue)
- Positron emission tomography (PET; used to detect metastasis and to help stage the disease)
When esophageal cancer is suspected, an esophagoscopy usually is performed. In this test, a thin tube with a light and camera attached (called an endoscope) is passed into the esophagus to allow the physician to visualize the mucosa (i.e., the lining) and detect abnormalities. Small instruments may be passed through the endoscope and used to remove a sample of tissue for microscopic examination (called a biopsy).
Once esophageal cancer is diagnosed, the stage of the disease is determined.