Utility of FDG-PET imaging in screening for succinate dehydrogenase B and D mutation-related lesions

Mutations of the genes encoding succinate dehydrogenase B and D (SDHB, SDHD) are associated with highly penetrant phenotypes, including paragangliomas and phaeochromocytomas. Patients with these mutations require lifelong surveillance; however, there is currently ambiguity regarding the optimal screening regimen. We sought to determine the utility of fluorodeoxyglucose (18F) positron emission tomography (18F-FDG PET) imaging, compared to other modalities for detecting SDHB and SDHD mutation-related lesions.

A retrospective audit of patients with SDHB or SDHD mutation.

All adult patients with confirmed SDHB and SDHD mutations who underwent 18F-FDG PET/CT at our institution between 1 July 2011 and 30 May 2015.

18F-FDG PET/computed tomography (CT) performed during surveillance of patients with SDHB and SDHD mutations. Lesion numbers and locations detected by 18F-FDG PET were compared to those identified on the CT component, as well as other imaging modalities and histology when available.

Thirty-one 18F-FDG PET/CT studies were completed on 22 patients. For SDHB (20 patients), there were five positive and 21 negative studies. There were no false-negative 18F-FDG PET studies. Positive 18F-FDG PET findings correlated with magnetic resonance imaging (MRI), CT and [68 Ga]-DOTA(0)-Tyr(3)-octreotate (68 Ga DOTATATE PET/CT) imaging with no missed lesions; the only potential false-positive result relating to nonspecific postoperative changes (sensitivity 100·0%, specificity 95·5%). For SDHD (two patients), lesions were detected on 18F-FDG PET and correlated with other imaging in three of five studies. Metastatic lesions were incompletely visualized on 18F-FDG PET but were detected on the noncontrast fusion CT.

18F-FDG PET/CT is suitable for detecting SDHB and SDHD mutation-related lesions and may be considered effective for periodic surveillance of patients with these mutations.