Esophageal Cancer: Diagnosis
Diagnosis is achieved through esophagoscopy and an upper GI series.
Esophagoscopy A thin, flexible tube is inserted through the mouth into the esophagus, allowing the physican to view the area, and to also take a tissue sample to be viewed under a microscope for the presence of cancer cells.
Upper GI series The patient swallows a barium contrast dye that moves through the esophagus into the stomach. An x-ray allows the physician to see how well fluid is passing through the esophagus.
Once diagnosis has been established, accurate staging of the cancer is necessary in order to permit optimum therapeutic decision-making. The stage of cancer, from 0 to IV, indicates how far it has spread. Stage 0 is the most contained, stage IV the most aggressive.
Three imaging methods are key in this process.
Endoscopic transesophageal ultrasound (EUS) uses sound waves to visualize tumor depth, surrounding lymph nodes, and the tumor's relationship to adjacent structures. It is often used in combination with two other imaging systems—PET (positron emission tomography) and CT scans—to accurately stage tumors of the esophagus.
During a PET scan a small amount of radionuclide glucose (sugar) is injected into a vein. The PET scanner rotates around the body and makes a picture of where glucose is being used in the body. Malignant tumor cells show up brighter than normal cells do.
A Computed Tomography (CT) scan takes data from several X-ray images of the body and converts them into pictures on a monitor.