Data from Superiority of [<sup>68</sup>Ga]-DOTATATE PET/CT to Other Functional Imaging Modalities in the Localization of <i>SDHB</i>-Associated Metastatic Pheochromocytoma and Paraganglioma

Abstract

<div>Abstract<p><b>Purpose:</b> Patients with succinate dehydrogenase subunit <i>B</i>(<i>SDHB</i>) mutation–related pheochromocytoma/paraganglioma (PHEO/PGL) are at a higher risk for metastatic disease than other hereditary PHEOs/PGLs. Current therapeutic approaches are limited, but the best outcomes are based on the early and proper detection of as many lesions as possible. Because PHEOs/PGLs overexpress somatostatin receptor 2 (SSTR2), the goal of our study was to assess the clinical utility of [<sup>68</sup>Ga]-DOTA(0)-Tyr(3)-octreotate ([<sup>68</sup>Ga]-DOTATATE) positron emission tomography/computed tomography (PET/CT) and to evaluate its diagnostic utility in comparison with the currently recommended functional imaging modalities [<sup>18</sup>F]-fluorodopamine ([<sup>18</sup>F]-FDA), [<sup>18</sup>F]-fluorodihydroxyphenylalanine ([<sup>18</sup>F]-FDOPA), [<sup>18</sup>F]-fluoro-2-deoxy-d-glucose ([<sup>18</sup>F]- FDG) PET/CT as well as CT/MRI.</p><p><b>Experimental Design:</b> [<sup>68</sup>Ga]-DOTATATE PET/CT was prospectively performed in 17 patients with <i>SDHB</i>-related metastatic PHEOs/PGLs. All patients also underwent [<sup>18</sup>F]-FDG PET/CT and CT/MRI, with 16 of the 17 patients also receiving [<sup>18</sup>F]-FDOPA and [<sup>18</sup>F]-FDA PET/CT scans. Detection rates of metastatic lesions were compared between all these functional imaging studies. A composite synthesis of all used functional and anatomical imaging studies served as the imaging comparator.</p><p><b>Results:</b> [<sup>68</sup>Ga]-DOTATATE PET/CT demonstrated a lesion-based detection rate of 98.6% [95% confidence interval (CI), 96.5%–99.5%], [<sup>18</sup>F]-FDG, [<sup>18</sup>F]-FDOPA, [<sup>18</sup>F]-FDA PET/CT, and CT/MRI showed detection rates of 85.8% (CI, 81.3%–89.4%; <i>P</i> < 0.01), 61.4% (CI, 55.6%–66.9%; <i>P</i> < 0.01), 51.9% (CI, 46.1%–57.7%; <i>P</i> < 0.01), and 84.8% (CI, 80.0%–88.5%; <i>P</i> < 0.01), respectively.</p><p><b>Conclusions:</b> [<sup>68</sup>Ga]-DOTATATE PET/CT showed a significantly superior detection rate to all other functional and anatomical imaging modalities and may represent the preferred future imaging modality in the evaluation of <i>SDHB</i>-related metastatic PHEO/PGL. <i>Clin Cancer Res; 21(17); 3888–95. ©2015 AACR</i>.</p><p><i>See related commentary by Hofman and Hicks, p. 3815</i></p></div>