Failure of MIBG scan to detect metastases in SDHB-mutated pediatric metastatic pheochromocytoma
123I-meta-iodo benzyl guanidine (MIBG) scans are considered the gold standard imaging in neuroblastoma; however, flouro deoxy glucose positron emission tomography (FDG-PET) scans have increased sensitivity in adults with pheochromocytoma/paraganglioma. We describe a pediatric patient initially considered to have localized neuroblastoma based on anatomical imaging and 123I-MIBG scan, but subsequent investigations revealed germline succinate dehydrogenase complex iron sulfur subunit B (SDHB) mutation–associated pheochromocytoma with multiple FDG-avid skeletal metastases. We then compared 123I-MIBG and FDG-PET scans in children with metastatic pheochromocytoma/paraganglioma. FDG-PET was superior to 123I-MIBG scan for the detection of skeletal metastases (median number of skeletal lesions detected 10 [range 1–30] vs. 2 [range 1–26], respectively; P = 0.005 by t-test). FDG-PET should be considered the functional scan of choice in children with pheochromocytoma/paraganglioma.