MD Anderson's experts use the most advanced technology and techniques to pinpoint esophageal cancer. Precise diagnosis often improves your chances for successful treatment. Since esophageal cancer often does not have symptoms in early stages, it may be found during procedures or tests for other conditions.
Esophageal Cancer Diagnostic Tests
If you have symptoms that may signal esophageal cancer, your doctor will examine you and ask you questions about your health; your 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 esophageal cancer and if it has spread. These tests also may be used to find out if treatment is working.
Imaging tests, which may include:
- CT or CAT (computed axial tomography) scans
- MRI (magnetic resonance imaging) scans
- PET (positron emission tomography) scans
One of the following methods may be used to biopsy tissue to find out if you have esophageal cancer:
Esophagoscopy: An endoscope is inserted through the mouth or nose into the esophagus. The doctor looks at the esophagus and removes small pieces of tissue.
Endoscopic ultrasound (EUS) or endosonography: An endoscope is inserted through an opening in the body, usually the mouth or rectum. At the end of the tube are a light, a tiny camera and a device that sends out ultrasound (high-energy sound) waves to make images of internal organs.
Video endoscopy: An endoscope with a special fiber-optic camera is inserted through the mouth, allowing the doctor to view the esophagus and biopsy the suspicious area.
Bronchoscopy: Using a tool called a bronchoscope, which is similar to the endoscope, the doctor looks at the trachea (windpipe) and the tubes that go into the lungs.
Laryngoscopy: With a tool called a laryngoscope, which is similar to the endoscope, the doctor examines the larynx (voice box).
Thoracoscopy: A small incision is made between two ribs, and an instrument called a thoracoscope is inserted through it into the chest. The thoracoscope is similar to the endoscope. It lets the doctor view and biopsy the lymph nodes inside the abdomen and chest.
(source: National Cancer Institute)
The most common system used to stage esophageal cancer is the TNM system of the American Joint Committee on Cancer (AJCC).
The TNM system describes three key pieces of information:
- T refers to the size of the primary tumor and how far it has spread within the esophagus and to nearby organs
- N refers to cancer spread to nearby lymph nodes
- M indicates whether the esophageal cancer has metastasized (spread to distant organs)
Staging also takes into account the cell type of the cancer and the grade of the cancer.
- Tis: The cancer is only in the epithelium (the top layer of cells lining the esophagus). It has not started growing into the deeper layers. This stage also is known as high-grade dysplasia. In the past it was called carcinoma in situ.
- T1: The cancer is growing into the tissue under the epithelium, such as the lamina propria, muscularis mucosa or submucosa
- T2: The cancer is growing into the muscle layer (muscularis propria)
- T3: The cancer is growing into the outer layer of tissue covering the esophagus (the adventitia)
- T4: The cancer is growing into nearby structures
- T4a: The cancer is growing into the pleura (the tissue covering the lungs), the pericardium (the tissue covering the heart), or the diaphragm. The cancer can be removed with surgery.
- T4b: The cancer cannot be removed with surgery because it has grown into the trachea (windpipe), aorta, spine or other crucial structures.
- N0: The cancer has not spread (metastasized) to nearby lymph nodes
- N1: The cancer has spread to one or two nearby lymph nodes
- N2: The cancer has spread to three to six nearby lymph nodes
- N3: The cancer has spread to seven or more nearby lymph nodes
- M0: The cancer has not spread (metastasized) to distant organs or lymph nodes
- M1: The cancer has spread to distant lymph nodes and/or other organs
The grade of a cancer is based on how normal (or differentiated) the cells appear when they are looked at under the microscope. The higher the number, the more abnormal the cells look. Higher-grade tumors tend to grow and spread faster than lower-grade tumors.
- GX: The grade cannot be assessed (treated in stage grouping as G1)
- G1: The cells are well differentiated
- G2: The cells are moderately differentiated
- G3: The cells are poorly differentiated
- G4: The cells are undifferentiated (these cells are so abnormal that doctors can't tell if they are adenocarcinoma or squamous cell carcinoma). For staging, G4 cancers are grouped with G3 squamous cell cancers.
Some staging of early squamous cell esophageal cancer also takes into account where the tumor is in the esophagus. The location is upper, middle or lower based on the location of the upper edge of the tumor.