Exp Clin Endocrinol Diabetes 2006; 114 - P01_002
DOI: 10.1055/s-2006-932888

Superiority of 6-[18F]- Fluorodopamin Positron Emission Tomography (DOPA-PET) versus [123J]-Metaiodobenzylguanidine (MIBG) scintigraphy in the localization of extraadrenal or multifocal pheochromocytomas and paragangliomas

C Fottner 1, A Helisch 2, M Schreckenberger 2, P Bartenstein 2, MM Weber 1
  • 1I. Medizinische Klinik und Poliklinik, Klinikum der Johannes Gutenberg Universität, Schwerpunkt Endokrinologie, Mainz, Germany
  • 2Klinik und Poliklinik für Nuklearmedizin, Klinikum der Johannes Gutenberg Universität, Mainz, Germany

Objective: The functional imaging of choice for a pheochromocytoma is [123J]-Metaiodobenzylguanidine (MIBG) scintigraphy. Recently published data show that alternatively [18F]DOPA-PET can be used to localize pheochromocytomas. The aim of the study was, to compare the diagnostic utility of DOPA-PET vs. MIBG-scintigraphy in patients with pheochromocytoma or paraganglioma (PHEO/PGL).

Methods: We studied 25 patients with biochemically confirmed PHEO/PGL. 2 patients had proven germline mutations in the RET gene, 9 patients in the SDHD- and 1 patient in the VHL-gene. In the 12 remaining patients, no mutation was found. Imaging modalities included computed tomography (CT) and/or magnetic resonance imaging (MRI) as well as both, MIBG-Scintigraphy and DOPA-PET. Lesions found by morphological and functional imaging were correlated with the histological findings.

Results: All 25 patients had positive adrenal or extraadrenal findings on CT/MRI, consistent with the presence of a PHE/PGL. DOPA-PET was positive in all patients but one with an extraadrenal abdominal PGL, whereas in contrast 9 patients had negative MIBG-Scintigraphy. All adrenal and extraadrenal abdominal lesions could be visualized by both DOPA-PET and MIBG-Scintigraphy. In contrast, only 1 of 19 extraadrenal thoracic and head and neck PGL was positive on MIBG-Scintigraphy, whereas all of them could be easily detected with DOPA-PET. Patients with multifocal and extraadrenal PHEO/PGL detected only with DOPA-PET showed a predominant secretion of noradrenaline/normetanephrine and almost exclusively occurred as part of hereditary pheochromocytoma syndromes. On histological examination, all lesions found with DOPA-PET imaging were shown to be PHEO/PGL, with malignant pheochromocytomas in 3 cases.

Conclusion: DOPA-PET was found to be a superior imaging method in patients with extraadrenal and multifocal pheochromocytomas, mostly due to hereditary syndromes or malignant pheochromocytomas, in which correct preoperative detection of disease extension determines the appropriate therapeutic approach and future follow up.