Performances of Functional and Anatomic Imaging Modalities in Succinate Dehydrogenase A- Related Metastatic Pheochromocytoma and Paraganglioma.

The study identifies the importance of positron emission tomographic (PET) and anatomic imaging modalities and their individual performances in detecting succinate dehydrogenase A ( SDHA) -related metastatic pheochromocytoma and paraganglioma (PPGL). The detection rates of PET modalities- 68 Ga-DOTATATE, 18 F-FDG, and 18 F-FDOPA-along with the combination of computed tomography (CT) and magnetic resonance imaging (MRI) are compared in a cohort of 11 patients with metastatic PPGL in the setting of a germline SDHA mutation. The imaging detection performances were evaluated at three levels: overall lesions, anatomic regions, and a patient-by-patient basis. 68 Ga-DOTATATE PET demonstrated a lesion-based detection rate of 88.6% [95% confidence interval (CI), 84.3-92.5%], while 18 F-FDG, 18 F-FDOPA, and CT/MRI showed detection rates of 82.9% (CI, 78.0-87.1%), 39.8% (CI, 30.2-50.2%), and 58.2% (CI, 52.0-64.1%), respectively. The study found that 68 Ga-DOTATATE best detects lesions in a subset of patients with SDHA- related metastatic PPGL. However, 18 F-FDG did detect more lesions in the liver, mediastinum, and abdomen/pelvis anatomic regions, showing the importance of a combined approach using both PET modalities in evaluating SDHA -related PPGL.