PET imaging performed at baseline and after the initiation of treatment "allowed prediction of response as early as after the first cycle of chemotherapy," said Norbert Avril, M.D., chief of the division of nuclear medicine at the University of Pittsburgh Medical Center, Pittsburgh, Pa. Conventional imaging procedures, such as computed tomography (CT), magnetic resonance imaging (MRI), plain film radiography and ultrasound, do not reliably predict therapy response early in the course of treatment, explained the co-author of "Early Prediction of Response to Chemotherapy in Metastatic Breast Cancer Using Sequential 18F-FDG PET."
Metastatic breast cancer is the most advanced stage of breast cancer. Cancer cells have spread past the breast and underarm lymph nodes to other areas of the body, continuing to grow, multiply and possibly spread to other regions of the body. Chemotherapy, which uses drugs to stop the growth of cancer cells, either by killing the cells or stopping the cells from dividing, is typically used with patients. At this advanced stage of the disease, the aim of treatment is to improve survival and quality of life, since the disease is generally not curable, said Avril. It's essential to identify those individuals who don't respond to chemotherapy early "to avoid ineffective therapies and unnecessary side effects," he noted. This ability to individualize treatment gives patients and physicians options not previously available, added Avril, indicating that additional studies are needed to determine how to use 18F-FDG PET in a clinical setting.