by C.H. Weaver M.D.
Accurate determination of the extent of spread of cancer (stage) in persons with esophageal cancer is imperative to define optimal treatment strategies. Positron emission tomography (PET) has recently emerged as a promising new staging method for some cancers, and according to a new study published in the
Journal of Oncology, PET scans also produce superior accuracy for detecting the extent of cancer in patients with esophageal cancer.
The esophagus is a muscular tube that conveys food from the back of the mouth to the stomach. Cancer of the esophagus, or esophageal cancer, is relatively uncommon, but is one of the most aggressive types of cancer. Prompt treatment is essential to increase chances for a cure. Since treatment options depend on the extent of the cancer, accuracy in staging is crucial in order to begin the most effective treatment without delay.
The use of PET may help doctors more accurately detect the presence and location of cancer cells in the body. A solution containing a type of sugar attached to a radioactive compound is injected into the vein of a patient undergoing a PET scan. Cancer cells tend to take up more sugar than normal cells, so the solution becomes concentrated in the cancer. The attached radioactive compound emits a form of radiation that can be detected by the PET scanner. A picture is then formed by the scanner, which can be visualized by the physician, to see the location of small amounts of cancer cells if they exist. Recent advances in technology allow the sensitive screening of the whole body in one examination session.
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In a recent study, researchers compared the accuracy of PET in 43 patients with cancer of the esophagus to standard staging methods. Initially, these patients underwent computerized tomography (CT) scans and ultrasonography of the esophagus to determine the stage of their cancer. Following this staging, all of the patients underwent a full body PET scan. Almost one third of the patients were found to have a different stage of cancer following their PET scan. PET scans detected more small cancers that had spread to localized lymph nodes.
From these results, physicians suggest that PET should be routinely used for the staging of all patients with the diagnosis of esophageal cancer. By better defining the stage of cancer, patients may be offered more effective treatment options. Importantly, the effective use of PET scanning may correctly identify which patients will benefit from aggressive surgical removal of their cancer and which patients may be spared treatment with an unnecessary surgery. Persons with cancer of the esophagus may wish to talk with their doctor about the use of PET to determine feasibility of surgery.
Journal of Clinical Oncology, Vol 18, No 18, pp 3202-3210, 2000)