Performance of ⁶⁸Ga-DOTA-Conjugated Somatostatin Receptor-Targeting Peptide PET in Detection of Pheochromocytoma and Paraganglioma: A Systematic Review and Metaanalysis

We performed a systematic review and metaanalysis of the performance of ⁶⁸Ga-DOTA-conjugated somatostatin receptor-targeting peptide (⁶⁸Ga-DOTA-SST) PET in the detection of pheochromocytomas and paragangliomas (PPGLs). Methods: PubMed and Embase were searched until May 8, 2018. We included studies that reported the detection rate of ⁶⁸Ga-DOTA-SST PET in patients with PPGLs. Detection rates were pooled using a random-effects model. Subgroup analyses and metaregression were performed to explore the cause of heterogeneity. Results: Thirteen studies were included for qualitative synthesis. Per-lesion detection rates of ⁶⁸Ga-DOTA-SST PET were consistently higher (ranging from 92% to 100%) than other imaging modalities, including ¹⁸F-fluorohydroxyphenylalanine (¹⁸F-FDOPA) PET, ¹⁸F-FDG PET, and ^123/131I-metaiodobenzylguanidine (^123/131I-MIBG) scintigraphy. However, in patients with polycythemia/paraganglioma syndrome, the detection rate of ⁶⁸Ga-DOTA-DOTATATE PET was 35%. Nine studies (215 patients) with no specific inclusion criteria for subtype were quantitatively synthesized. The pooled detection rate was 93% (95% confidence interval [CI], 91%-95%), which was significantly higher than that of ¹⁸F-FDOPA PET (80% [95% CI, 69%-88%]), ¹⁸F-FDG PET (74% [95% CI, 46%-91%]), and ^123/131I-MIBG scan (38% [95% CI, 20%-59%], P < 0.001 for all). A greater prevalence of head and neck paragangliomas was associated with higher detection rates of ⁶⁸Ga-DOTA-SST PET (P = 0.0002). Conclusion:⁶⁸Ga-DOTA-SST PET exhibited superior performance for lesion detection, over other functional imaging modalities, in patients with PPGLs, with the exception of polycythemia/paraganglioma syndrome. This might suggest ⁶⁸Ga-DOTA-SST PET as a first-line imaging modality for the primary staging of PPGL or the restaging of PPGL with unknown genetic status.