title: Nuclear imaging to characterize adrenal tumors: Comparison with MRI.
abstract: OBJECTIVE
  To describe the role of nuclear imaging modalities using nor-cholesterol, metaiodobenzylguanidine (MIBG) and fluorine-deoxy-glucose (FDG) in adrenal tumors for lesion characterization in comparison with magnetic resonance (MR).
  
  
  METHODS
  Population was classified in group 1 consisting of 30 patients with non-hypersecreting unilateral adrenal masses, in group 2 consisting of 34 patients with hypersecreting (n = 19) or non-hypersecreting (n = 15) adrenal adenomas and in group 3 consisting of 18 patients with chromaffin-tissue tumors (CTT), of which 14 were pheochromocytomas while 4 were paragangliomas (n = 4). All patients underwent MR and nuclear studies (nor-cholesterol, MIBG and FDG). Pathology samples (n = 63) or follow-up data in adenomas (n = 19) were used as standard of reference for imaging studies interpretation.
  
  
  RESULTS
  In group 1, MR findings were not highly accurate for lesion characterization, while the results of nuclear scans showed abnormal nor-cholesterol, MIBG and FDG concentration in all cases of adenomas, pheos and malignant tumors, respectively. In group 2, no differences in MR parameters were found between hyperfunctioning and non-hyperfunctioning adenomas, while nor-cholesterol uptake was significantly higher in hyperfunctioning compared to non-hyperfunctioning lesions. In group 3, no differences in MR parameters were found between benign and malignant CCT, while MIBG uptake was significantly higher in malignant compared to benign tumors.
  
  
  CONCLUSIONS
  On the basis of our findings, nuclear imaging modalities using specific target agents are able to better characterize adrenal tumors, compared with MR. In particular, radionuclide techniques are able to identify the nature of adrenal incidentalomas and to differentiate between hypersecreting and non-hypersecreting adenomas as well as between benign and malignant CTT.
authors: Simone Maurea, Pier Paolo Mainenti, Valeria Romeo, Carmine Mollica, Marco Salvatore, Medicina Nucleare e Radiologia, Dipartimento di Scienze Biomediche Avanzate, Università degli Studi di Napoli Federico II (UNINA), 80123 Napoli, Italy.
authors: Simone
authors: S
authors: Maurea
authors: Simone Maurea, Pier Paolo Mainenti, Valeria Romeo, Carmine Mollica, Marco Salvatore, Medicina Nucleare e Radiologia, Dipartimento di Scienze Biomediche Avanzate, Università degli Studi di Napoli Federico II (UNINA), 80123 Napoli, Italy.
authors: Pier Paolo
authors: PP
authors: Mainenti
authors: Simone Maurea, Pier Paolo Mainenti, Valeria Romeo, Carmine Mollica, Marco Salvatore, Medicina Nucleare e Radiologia, Dipartimento di Scienze Biomediche Avanzate, Università degli Studi di Napoli Federico II (UNINA), 80123 Napoli, Italy.
authors: Valeria
authors: V
authors: Romeo
authors: Simone Maurea, Pier Paolo Mainenti, Valeria Romeo, Carmine Mollica, Marco Salvatore, Medicina Nucleare e Radiologia, Dipartimento di Scienze Biomediche Avanzate, Università degli Studi di Napoli Federico II (UNINA), 80123 Napoli, Italy.
authors: Carmine
authors: C
authors: Mollica
authors: Simone Maurea, Pier Paolo Mainenti, Valeria Romeo, Carmine Mollica, Marco Salvatore, Medicina Nucleare e Radiologia, Dipartimento di Scienze Biomediche Avanzate, Università degli Studi di Napoli Federico II (UNINA), 80123 Napoli, Italy.
authors: Marco
authors: M
authors: Salvatore
keywords: Adrenals; Fluorine-deoxy-glucose; Magnetic resonance imaging; Metaiodobenzylguanidine; Nor-cholesterol; Tumors