title: Carbidopa-assisted18F-fluorodihydroxyphenylalanine PET/CT for the localization and staging of non-functioning neuroendocrine pancreatic tumors.
abstract: OBJECTIVE
  CD premedication was found to increase the value of18F-fluorodihydroxyphenylalanine (18F-FDOPA) PET/CT imaging in the detection of adult insulinoma. The aim of this study was to evaluate the performance of CD-assisted18F-FDOPA PET/CT in the diagnosis and staging of non-functioning pNETs.
  
  
  METHODS
  Twenty consecutive patients with low-grade pNETs who underwent CD-assisted18F-FDOPA PET/CT imaging and111In-somatostatin receptor scintigraphy (SRS) were evaluated. Histology was considered as the gold standard. In case where no surgical resection was performed, the diagnosis of pNET was made by the confrontation of the different available imaging modalities.
  
  
  RESULTS
  CD-assisted18F-FDOPA PET/CT was positive in 18/20 cases (90 %), whereas SRS was positive in 13/19 cases (68 %). When considered the 19 patients underwent both nuclear medicine examinations,18F-FDOPA PET/CT was significantly more sensitive then SRS for primary tumor detection (p = 0.049). False-negative results of both18F-FDOPA PET/CT and SRS were observed in 2 cystic pNETs. SRS failed to detect one additional cystic tumor and 3 pNETs of 10, 12 and 17 mm, respectively.18F-FDOPA PET/CT correctly identified all patients with lymphatic, visceral and bone metastases. SRS failed to detect lymphatic spread and was falsely negative in one patient with splenic metastasis.
  
  
  CONCLUSIONS
  Contrary to widely held assumptions, our study further expands the application of CD-assisted18F-FDOPA PET/CT for non-functioning pNETs when68Ga-radiolabeled somatostatin analogs are not available.
authors.affiliation: Biophysics and Nuclear Medicine, Hautepierre University Hospital, 1, Avenue Molière, 67098, Strasbourg Cedex 09, France.
authors.forename: Mehdi
authors.initials: M
authors.lastname: Helali
authors.affiliation: Visceral Surgery and Transplantation, Hautepierre University Hospital, Strasbourg, France.
authors.forename: Pietro
authors.initials: P
authors.lastname: Addeo
authors.affiliation: Biophysics and Nuclear Medicine, Hautepierre University Hospital, 1, Avenue Molière, 67098, Strasbourg Cedex 09, France.
authors.forename: Céline
authors.initials: C
authors.lastname: Heimburger
authors.affiliation: Biophysics and Nuclear Medicine, Hautepierre University Hospital, 1, Avenue Molière, 67098, Strasbourg Cedex 09, France.|Radiopharmacy, Hautepierre University Hospital, Strasbourg, France.
authors.forename: Julien
authors.initials: J
authors.lastname: Detour
authors.affiliation: Internal Medicine, Hautepierre University Hospital, Strasbourg, France.
authors.forename: Bernard
authors.initials: B
authors.lastname: Goichot
authors.affiliation: Visceral Surgery and Transplantation, Hautepierre University Hospital, Strasbourg, France.
authors.forename: Philippe
authors.initials: P
authors.lastname: Bachellier
authors.affiliation: Biophysics and Nuclear Medicine, Hautepierre University Hospital, 1, Avenue Molière, 67098, Strasbourg Cedex 09, France.|ICube, CNRS (UMR 7357), Fédération de Médecine Translationnelle de Strasbourg (FMTS), Faculty of Medicine, University of Strasbourg, Strasbourg, France.
authors.forename: Izzie Jacques
authors.initials: IJ
authors.lastname: Namer
authors.affiliation: Nuclear Medicine, La Timone University Hospital, Aix-Marseille University, Marseille, France.|European Center for Research in Medical Imaging, Aix-Marseille University, Marseille, France.|Inserm UMR1068 Marseille Cancerology Research Center, Institut Paoli-Calmettes, Marseille, France.
authors.forename: David
authors.initials: D
authors.lastname: Taïeb
authors.affiliation: Biophysics and Nuclear Medicine, Hautepierre University Hospital, 1, Avenue Molière, 67098, Strasbourg Cedex 09, France. alessio.imperiale@chru-strasbourg.fr.|ICube, CNRS (UMR 7357), Fédération de Médecine Translationnelle de Strasbourg (FMTS), Faculty of Medicine, University of Strasbourg, Strasbourg, France. alessio.imperiale@chru-strasbourg.fr.
authors.forename: Alessio
authors.initials: A
authors.lastname: Imperiale
mesh_terms: D000328:Adult; D000368:Aged; D002230:Carbidopa / Q000494:pharmacology*; D004295:Dihydroxyphenylalanine / Q000031:analogs & derivatives*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D018358:Neuroendocrine Tumors / Q000000981:diagnostic imaging* / Q000473:pathology*; D010190:Pancreatic Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology*; D000072078:Positron Emission Tomography Computed Tomography / Q000379:methods*
chemical_list: C043437:fluorodopa F 18; D004295:Dihydroxyphenylalanine; D002230:Carbidopa
keywords: 18F-FDOPA; Carbidopa; Neuroendocrine tumors; PET/CT; Pancreas