PET/CT comparing 68Ga DOTATATE and other radiopharmaceuticals and in comparison with CT/MRI for the localization of sporadic metastatic pheochromocytoma and paraganglioma
PurposePheochromocytomas/paragangliomas (PPGLs) and their metastases are tumors that predominantly express somatostatin receptor 2 (SSR2) 68Ga DOTA(0) Tyr(3) octreotate (68Ga DOTATATE) is a PET radiopharmaceutical with both high and selective affinity for SSRs. The purpose of this study was to evaluate the utility of 68Ga DOTATATE in comparison with other specific and nonspecific radiopharmaceuticals recommended in the current guidelines for the localization of metastatic sporadic PPGL by PET/CT.MethodsThis prospective study included 22 patients (15 men, 7 women; aged 50.0 13.9 years) with confirmed metastatic PPGL, a negative family history for PPGL, and negative genetic testing, who underwent 68Ga DOTATATE, 18F fluoro 2 deoxy D glucose (18F FDG) PET/CT, and CT/MRI. Only 12 patients underwent an additional 18F fluorodihydroxyphenylalanine (18F FDOPA) PET/CT scan and only 11 patients underwent an additional 18F fluorodopamine (18F FDA) PET/CT scan. The rates of detection of metastatic lesions were compared among all the imaging studies. A composite of all functional and anatomical imaging studies served as the imaging comparator.Results68Ga DOTATATE PET/CT showed a lesion based detection rate of 97.6 (95 confidence interval, CI, 95.8 98.7 18F FDG PET/CT, 18F FDOPA PET/CT, 18F FDA PET/CT, and CT/MRI showed detection rates of 49.2 (CI 44.5 53.6 p 0.01) 74.8 (CI 69.0 79.9 p 0.01) 77.7 (CI 71.5 82.8 p 0.01) and 81.6 (CI 77.8 84.8 p 0.01) respectively.ConclusionThe results of this study demonstrate the superiority of 68Ga DOTATATE PET/CT in the localization of sporadic metastatic PPGLs compared to all other functional and anatomical imaging modalities, and suggest modification of future guidelines towards this new imaging modality.
European Journal of Nuclear Medicine and Molecular Imaging