title: Molecular imaging of 1p/19q deletion in oligodendroglial tumours with 11C-methionine positron emission tomography.
abstract: OBJECTIVE
  Chromosome 1p/19q deletion is an established prognostic and predictive marker in the WHO grade III oligodendroglial tumours (OT). To estimate the genetic status preoperatively, the authors investigated the correlation between the uptake of (11)C-methionine in positron emission tomography (PET) and the 1p/19q status in grades II and III OT.
  
  
  METHODS
  We retrospectively reviewed 144 patients with gliomas who received (11)C-methionine PET. 66 cases with grades II-III oligodendrogliomas or oligoastrocytomas underwent fluorescence in situ hybridisation to determine the 1p/19q status. The tissue uptake of (11)C-methionine was expressed as the ratio of the maximum standardised uptake value (SUVmax) in tumour areas to the mean SUV (SUVmean) in the contralateral normal brain (tumour-to-normal tissue (T/N) ratio).
  
  
  RESULTS
  The T/N ratio in (11)C-methionine PET was significantly higher in grade III OT than in grade II tumours. The mean T/N ratio of the grade II tumours without 1p/19q deletion was significantly higher than that of the grade II tumours with 1p/19q deletion (mean 2.67 vs 1.94, respectively; p=0.0457). In grade III tumours, the mean T/N ratio of the tumours without 1p/19q deletion was also significantly higher than that of the tumours with 1p/19q deletion (mean 4.83 vs 3.49, respectively; p=0.0261). The rate of IDH1 mutation was lower and the rate of contrast enhancement on MRIs was higher in the 1p/19q non-deleted OT than those with 1p/19q deletion, which may contribute to the high T/N ratio.
  
  
  CONCLUSIONS
  Among suspected OT, (11)C-methionine PET may help us preoperatively discriminate tumours with and without 1p/19q deletion.
authors: Department of Neurological Surgery, Chiba University Graduate School of Medicine, Chiba, Japan.
authors: Yasuo
authors: Y
authors: Iwadate
authors: Department of Neurological Surgery, Chiba University Graduate School of Medicine, Chiba, Japan Department of Neurosurgery, Narita Red-Cross Hospital, Chiba, Japan.
authors: Natsuki
authors: N
authors: Shinozaki
authors: Department of Neurological Surgery, Chiba University Graduate School of Medicine, Chiba, Japan.
authors: Tomoo
authors: T
authors: Matsutani
authors: Chiba Medical Center for Prolonged Traumatic Brain Dysfunction, Chiba, Japan National Institute of Radiological Science, Chiba, Japan.
authors: Yoshio
authors: Y
authors: Uchino
authors: Department of Neurological Surgery, Chiba University Graduate School of Medicine, Chiba, Japan.
authors: Naokatsu
authors: N
authors: Saeki
mesh_terms: D001932:Brain Neoplasms / Q000000981:diagnostic imaging* / Q000235:genetics / Q000473:pathology; D002872:Chromosome Deletion; D002878:Chromosomes, Human, Pair 1 / Q000235:genetics; D002888:Chromosomes, Human, Pair 19 / Q000235:genetics; D005260:Female; D006801:Humans; D008297:Male; D008715:Methionine / Q000031:analogs & derivatives; D008875:Middle Aged; D057054:Molecular Imaging / Q000379:methods*; D009837:Oligodendroglioma / Q000000981:diagnostic imaging* / Q000235:genetics / Q000473:pathology; D049268:Positron-Emission Tomography / Q000379:methods*; D011379:Prognosis; D011859:Radiography; D019275:Radiopharmaceuticals; D012189:Retrospective Studies
chemical_list: D019275:Radiopharmaceuticals; D008715:Methionine