Aggressive Imaging Features in a Malignant Pheochromocytoma With a Novel Mutation of the SDHB Gene

: We describe a 15-year-old boy with a huge bilateral adrenal pheochromocytoma that had a de novo germline mutation in the succinate dehydrogenase subunit B (SDHB) gene. F-FDG PET/CT revealed bilateral metabolically active large masses in the adrenal glands and the activated brown adipose tissues. The I-MIBG scintigraphic findings revealed only a mild accumulation of MIBG in the right adrenal mass, but a high uptake in the left adrenal mass. Thus, F-FDG PET/CT imaging may be more effective than I-MIBG scintigraphy for the evaluation of pheochromocytomas that are associated with highly malignant characteristics resulting from mutations of the SDHB gene.