| Abstract: |
Context: Besides <sup>123</sup>I-metaiodobenzylguanidine (MIBG), positron emission tomography (PET) agents are available for the localization of paraganglioma (PGL), including <sup>18</sup>F-3,4-dihydroxyphenylalanine (DOPA), <sup>18</sup>F-fluoro-2-deoxy-D-glucose (<sup>18</sup>F-FDG), and <sup>18</sup>F-fluorodopamine (<sup>18</sup>F-FDA). Objective: The objective of the study was to establish the optimal approach to the functional imaging of PGL and examine the link between genotype-specific tumor biology and imaging. Design: This was a prospective observational study. Intervention: There were no interventions. Patients: Fifty-two patients (28 males, 24 females, aged 46.8±14.2 yr): 20 with nonmetastatic PGL (11 adrenal), 28 with metastatic PGL (13 adrenal), and four in whom PGL was ruled out; 22 PGLs were of the succinate dehydrogenase subunit B (SDHB) genotype. Main Outcome Measures: Sensitivity of <sup>18</sup>F-DOPA, <sup>18</sup>F-FDG, and <sup>18</sup>F-FDA PET, <sup>123</sup>I-MIBG scintigraphy, computed tomography (CT), and magnetic resonance imaging (MRI) for the localization of PGL were measured. Results: Sensitivities for localizing nonmetastatic PGL were 100% for CT and/or MRI, 81% for <sup>18</sup>F-DOPA PET, 88% for <sup>18</sup>F-FDG PET/CT, 78% for <sup>18</sup>F-FDA PET/CT, and 78% for <sup>123</sup>I-MIBG scintigraphy. For metastatic PGL, sensitivity in reference to CT/MRI was 45% for <sup>18</sup>F-DOPA PET, 74% for <sup>18</sup>F-FDG PET/CT, 76% for <sup>18</sup>F-FDA PET/CT, and 57% for <sup>123</sup>I-MIBG scintigraphy. In patients with SDHB metastatic PGL, <sup>18</sup>F-FDA and <sup>18</sup>F-FDG have a higher sensitivity (82 and 83%) than <sup>123</sup>I-MIBG (57%) and <sup>18</sup>F-DOPA (20%). Conclusions: <sup>18</sup>F-FDA PET/CT is the preferred technique for the localization of the primary PGL and to rule out metastases. Second best, equal alternatives are <sup>18</sup>F-DOPA PET and <sup>123</sup>I-MIBG scintigraphy. For patients with known metastatic PGL, we recommend <sup>18</sup>F-FDA PET in patients with an unknown genotype, <sup>18</sup>F-FDG or <sup>18</sup>F-FDA PET in SDHB mutation carriers, and <sup>18</sup>F-DOPA or <sup>18</sup>F-FDA PET in non-SDHB patients. Copyright © 2009 by The Endocrine Society. |
