Evaluation of cancer detection with whole-body positron emission tomography (PET) and 2-[F-18]fluoro-2-deoxy-D-glucose

Until recently, positron emission tomography (PET) has been acquired and displayed in a standard transaxial image format. The development of whole body PET has allowed biochemical and physiologic imaging of the entire body, expanding the limited axial field of view of the conventional PET scanner. In this study, the application of whole body PET studies with 2-[F-18]fluoro-2-deoxy-D-glucose (FDG) for tumor imaging was evaluated. Whole body PET studies were positive (presence of focal FDG uptake relative to surrounding tissue activity) in 61 of 70 patients (87%) with biopsy confirmed malignant tumors. PET images failed to reveal focal hypermetabolism in 9 of the 70 patients. Of the 17 patients with benign biopsies lesions, 13 patients had whole body PET studies without focal areas of FDG uptake. Because of the high glycolytic rate of malignant tissue, the whole body PET FDG technique has promise in the detection of a wide variety of both primary and metastatic malignancies. The presence of FDG uptake in benign inflammatory conditions may limit the specificity of the technique. The true positive rates for the characterization of known lesions was 87% in this series, and the PET FDG method is promising both in determining both the nature of a localized lesion, and in defining the systemic extent of malignant disease.