title: Accuracy of distinguishing between dysembryoplastic neuroepithelial tumors and other epileptogenic brain neoplasms with [¹¹C]methionine PET.
abstract: BACKGROUND
  Dysembryoplastic neuroepithelial tumors (DNTs) represent a prevalent cause of epileptogenic brain tumors, the natural evolution of which is much more benign than that of most gliomas. Previous studies have suggested that [(11)C]methionine positron emission tomography (MET-PET) could help to distinguish DNTs from other epileptogenic brain tumors, and hence optimize the management of patients. Here, we reassessed the diagnostic accuracy of MET-PET for the differentiation between DNT and other epileptogenic brain neoplasms in a larger population.
  
  
  METHODS
  We conducted a retrospective study of 77 patients with focal epilepsy related to a nonrapidly progressing brain tumor on MRI who underwent MET-PET, including 52 with a definite histopathology. MET-PET data were assessed by a structured visual analysis that distinguished normal, moderately abnormal, and markedly abnormal tumor methionine uptake and by semiquantitative ratio measurements.
  
  
  RESULTS
  Pathology showed 21 DNTs (40%), 10 gangliogliomas (19%), 19 low-grade gliomas (37%), and 2 high-grade gliomas (4%). MET-PET visual findings significantly differed among the various tumor types (P < .001), as confirmed by semiquantitative analyses (P < .001 for all calculated ratios), regardless of gadolinium enhancement on MRI. All gliomas and gangliogliomas were associated with moderately or markedly increased tumor methionine uptake, whereas 9/21 DNTs had normal methionine uptake. Receiver operating characteristics analysis of the semiquantitative ratios showed an optimal cutoff threshold that distinguished DNTs from other tumor types with 90% specificity and 89% sensitivity.
  
  
  CONCLUSIONS
  Normal MET-PET findings in patients with an epileptogenic nonrapidly progressing brain tumor are highly suggestive of DNT, whereas a markedly increased tumor methionine uptake makes this diagnosis unlikely.
authors.affiliation: Department of Functional Neurology and Epileptology and Institute of Epilepsies (IDEE) (S.Rh., E.B., P.R.); Department of Pathology (N.S.); Department of Functional Neurosurgery (M.G.); Hospices Civils de Lyon, Lyon, France; Lyon Neuroscience Research Center, INSERM U1028/CNRS UMR5292, Lyon, France (S.Rh., S.B., P.R.); CERMEP-Imagerie du Vivant, Lyon, France (S.B., D.L.B.); Neurodis Foundation, CERMEP-Imagerie du Vivant, Lyon, France (A.H.); Hospital Clinic de Barcelona, Barcelona, Spain (S.Ru.).
authors.forename: Sylvain
authors.initials: S
authors.lastname: Rheims
authors.affiliation: Department of Functional Neurology and Epileptology and Institute of Epilepsies (IDEE) (S.Rh., E.B., P.R.); Department of Pathology (N.S.); Department of Functional Neurosurgery (M.G.); Hospices Civils de Lyon, Lyon, France; Lyon Neuroscience Research Center, INSERM U1028/CNRS UMR5292, Lyon, France (S.Rh., S.B., P.R.); CERMEP-Imagerie du Vivant, Lyon, France (S.B., D.L.B.); Neurodis Foundation, CERMEP-Imagerie du Vivant, Lyon, France (A.H.); Hospital Clinic de Barcelona, Barcelona, Spain (S.Ru.).
authors.forename: Sebastià
authors.initials: S
authors.lastname: Rubi
authors.affiliation: Department of Functional Neurology and Epileptology and Institute of Epilepsies (IDEE) (S.Rh., E.B., P.R.); Department of Pathology (N.S.); Department of Functional Neurosurgery (M.G.); Hospices Civils de Lyon, Lyon, France; Lyon Neuroscience Research Center, INSERM U1028/CNRS UMR5292, Lyon, France (S.Rh., S.B., P.R.); CERMEP-Imagerie du Vivant, Lyon, France (S.B., D.L.B.); Neurodis Foundation, CERMEP-Imagerie du Vivant, Lyon, France (A.H.); Hospital Clinic de Barcelona, Barcelona, Spain (S.Ru.).
authors.forename: Sandrine
authors.initials: S
authors.lastname: Bouvard
authors.affiliation: Department of Functional Neurology and Epileptology and Institute of Epilepsies (IDEE) (S.Rh., E.B., P.R.); Department of Pathology (N.S.); Department of Functional Neurosurgery (M.G.); Hospices Civils de Lyon, Lyon, France; Lyon Neuroscience Research Center, INSERM U1028/CNRS UMR5292, Lyon, France (S.Rh., S.B., P.R.); CERMEP-Imagerie du Vivant, Lyon, France (S.B., D.L.B.); Neurodis Foundation, CERMEP-Imagerie du Vivant, Lyon, France (A.H.); Hospital Clinic de Barcelona, Barcelona, Spain (S.Ru.).
authors.forename: Emilien
authors.initials: E
authors.lastname: Bernard
authors.affiliation: Department of Functional Neurology and Epileptology and Institute of Epilepsies (IDEE) (S.Rh., E.B., P.R.); Department of Pathology (N.S.); Department of Functional Neurosurgery (M.G.); Hospices Civils de Lyon, Lyon, France; Lyon Neuroscience Research Center, INSERM U1028/CNRS UMR5292, Lyon, France (S.Rh., S.B., P.R.); CERMEP-Imagerie du Vivant, Lyon, France (S.B., D.L.B.); Neurodis Foundation, CERMEP-Imagerie du Vivant, Lyon, France (A.H.); Hospital Clinic de Barcelona, Barcelona, Spain (S.Ru.).
authors.forename: Nathalie
authors.initials: N
authors.lastname: Streichenberger
authors.affiliation: Department of Functional Neurology and Epileptology and Institute of Epilepsies (IDEE) (S.Rh., E.B., P.R.); Department of Pathology (N.S.); Department of Functional Neurosurgery (M.G.); Hospices Civils de Lyon, Lyon, France; Lyon Neuroscience Research Center, INSERM U1028/CNRS UMR5292, Lyon, France (S.Rh., S.B., P.R.); CERMEP-Imagerie du Vivant, Lyon, France (S.B., D.L.B.); Neurodis Foundation, CERMEP-Imagerie du Vivant, Lyon, France (A.H.); Hospital Clinic de Barcelona, Barcelona, Spain (S.Ru.).
authors.forename: Marc
authors.initials: M
authors.lastname: Guenot
authors.affiliation: Department of Functional Neurology and Epileptology and Institute of Epilepsies (IDEE) (S.Rh., E.B., P.R.); Department of Pathology (N.S.); Department of Functional Neurosurgery (M.G.); Hospices Civils de Lyon, Lyon, France; Lyon Neuroscience Research Center, INSERM U1028/CNRS UMR5292, Lyon, France (S.Rh., S.B., P.R.); CERMEP-Imagerie du Vivant, Lyon, France (S.B., D.L.B.); Neurodis Foundation, CERMEP-Imagerie du Vivant, Lyon, France (A.H.); Hospital Clinic de Barcelona, Barcelona, Spain (S.Ru.).
authors.forename: Didier
authors.initials: D
authors.lastname: Le Bars
authors.affiliation: Department of Functional Neurology and Epileptology and Institute of Epilepsies (IDEE) (S.Rh., E.B., P.R.); Department of Pathology (N.S.); Department of Functional Neurosurgery (M.G.); Hospices Civils de Lyon, Lyon, France; Lyon Neuroscience Research Center, INSERM U1028/CNRS UMR5292, Lyon, France (S.Rh., S.B., P.R.); CERMEP-Imagerie du Vivant, Lyon, France (S.B., D.L.B.); Neurodis Foundation, CERMEP-Imagerie du Vivant, Lyon, France (A.H.); Hospital Clinic de Barcelona, Barcelona, Spain (S.Ru.).
authors.forename: Alexander
authors.initials: A
authors.lastname: Hammers
authors.affiliation: Department of Functional Neurology and Epileptology and Institute of Epilepsies (IDEE) (S.Rh., E.B., P.R.); Department of Pathology (N.S.); Department of Functional Neurosurgery (M.G.); Hospices Civils de Lyon, Lyon, France; Lyon Neuroscience Research Center, INSERM U1028/CNRS UMR5292, Lyon, France (S.Rh., S.B., P.R.); CERMEP-Imagerie du Vivant, Lyon, France (S.B., D.L.B.); Neurodis Foundation, CERMEP-Imagerie du Vivant, Lyon, France (A.H.); Hospital Clinic de Barcelona, Barcelona, Spain (S.Ru.).
authors.forename: Philippe
authors.initials: P
authors.lastname: Ryvlin
mesh_terms: D000293:Adolescent; D000328:Adult; D001932:Brain Neoplasms / Q000150:complications / Q000000981:diagnostic imaging*; D002250:Carbon Radioisotopes; D002648:Child; D002675:Child, Preschool; D004827:Epilepsy / Q000150:complications*; D005260:Female; D006801:Humans; D008297:Male; D008715:Methionine; D008875:Middle Aged; D018302:Neoplasms, Neuroepithelial / Q000150:complications / Q000000981:diagnostic imaging*; D049268:Positron-Emission Tomography; D012680:Sensitivity and Specificity; D013724:Teratoma / Q000150:complications / Q000000981:diagnostic imaging*; D055815:Young Adult
chemical_list: D002250:Carbon Radioisotopes; D008715:Methionine
keywords: brain tumor; dysembryoplastic neuroepithelial tumor; epilepsy; methionine PET