PET stands for positron emission tomography and it detects changes in cellular function – how cells are utilizing nutrients like sugar and oxygen. Areas with a high degree of metabolic activity have a greater chance of being cancerous. A computerized tomography or CT scan allows physicians to see the internal or anatomical structures within the human body. Together these two technologies make up the revolutionary PET/CT scan that enable Fox Chase physicians to view metabolic activity and pinpoint the location of abnormal lesions to target the disease more precisely.
"When used alone the PET and CT scans are good diagnostic tools, but when combined, they're much superior," says Adler. "The advantage here is the cancer is highlighted on the computer screen. We're able to pinpoint the location of the cancer, determine the extent of the disease, and evaluate the effectiveness of the patient's treatment," says Adler.
The PET/CT unit will be used at Fox Chase to determine if tumors are benign or malignant, to examine if prior therapy has been effective, and to detect if cancer has spread to other parts of the body. This technology will be particularly useful to more accurately diagnose and stage cancers of the lung, colon, breast, esophagus, and head and neck.
Before undergoing PET/CT, patients receive an injection of a sugar substance called fluorodeoxyglucose (FDG). This substance travels to cells throughout the entire body and is completely harmless. Since most cancerous tumors are highly metabolic, more of the FDG sugar substance goes to the cancer than to the normal tissue. During the procedure, the patient lies flat on a table that moves through a wide opening in the machine while the PET/CT images are taken. The areas within the body that absorb the FDG sugar are highlighted on the PET/CT computer screen indicating that cancer is present.
"We traditionally use CT scans to diagnose patients with cancer, however, we don't always know how extensive the disease is until we operate," says Melvyn Goldberg, MD, chief of Fox Chase's thoracic surgery program. "With PET/CT, we'll be able to more accurately stage our patients and avoid diagnostic surgeries. The PET/CT has the capability of finding cancers including those that have spread to other organs that are 8 millimeters in size, which is a huge improvement over CT alone," explains Goldberg.
The PET/CT unit, purchased from General Electric, is located in Fox Chase Cancer Center's radiology department. Currently, Medicare and most major insurance companies reimburse for PET/CT. Breast cancer cases will be covered by Medicare beginning in October, 2002.
Fox Chase Cancer Center, one of the nation's first comprehensive cancer centers designated by the National Cancer Institute in 1974, conducts basic and clinical research; programs of prevention, detection and treatment of cancer; and community outreach. For more information about Fox Chase activities, visit the Center's web site at www.fccc.edu or call 1-888-FOX CHASE.