Purpose: To assess the uptake in neuroblastoma of 2-[fluorine-18] -fluoro-2-deoxy-D-glucose (FDG) versus metaiodobenzylguanidine (MIBG).
Materials and methods: Seventeen patients with known or suspected neuroblastoma underwent FDG positron emission tomography (PET) (20 scans) and MIBG scintigraphy. Tumor uptake of FDG was quantified on positive PET scans.
Results: Tumor uptake of FDG was detected in 16 of 17 patients (18 of 20 scans). Neuroblastomas and their metastases avidly concentrated FDG prior to chemotherapy or radiation therapy. Uptake after therapy was variable. Uptake of FDG was intense in one patient with neuroblastoma that failed to accumulate MIBG. In 13 of the 20 scans, however, MIBG was rated superior to FDG for delineation of tumor compared with background and normal organs.
Conclusion: Most neuroblastomas accumulate FDG. The mechanism of MIBG uptake is more intense prior to therapy. Concentration of FDG is not dependent on type 1 catecholamine uptake. FDG PET helps define the distribution of neuroblastomas that fail to concentrate MIBG.