title: Rapid and sensitive intraoperative detection of mutations in the isocitrate dehydrogenase 1 and 2 genes during surgery for glioma.
abstract: OBJECTIVE
  Intraoperative diagnosis is important in determining the strategies during surgery for glioma. Because the mutations in the isocitrate dehydrogenase 1 and 2 (IDH1 and IDH2) genes have diagnostic, prognostic, and predictive values, the authors assessed the feasibility and significance of a simplified method for the intraoperative detection of IDH1 and IDH2 gene mutations.
  
  
  METHODS
  Rapid DNA extraction, amplification with conventional polymerase chain reaction (PCR) or co-amplification at lower denaturation temperature PCR (COLD-PCR), and fluorescence melting curve analysis with adjacent hybridization probes were performed for the intraoperative detection of IDH1 and IDH2 mutations in 18 cases of suspected nonneoplastic lesions and low- and high-grade gliomas and in 3 cases of radiation necrosis.
  
  
  RESULTS
  DNA extraction for detection of the mutation took 60-65 minutes. The results of this assay showed complete correlation with that of Sanger sequencing. The sensitivity for detection of mutations in a background of wild-type genes was 12.5% and 2.5% in conventional PCR and COLD-PCR, respectively. The diagnosis of glioma was established in 3 of 5 cases in which definitive diagnosis was not obtained using frozen sections, and information was obtained for the discrimination of glioblastoma or glioblastoma with an oligodendroglioma component from anaplastic glioma or secondary glioblastoma. This assay also detected a small fraction of tumor cells with IDH1 mutation in radiation necrosis.
  
  
  CONCLUSIONS
  These methods provide important information for establishing the differential diagnosis between low-grade glioma and nonneoplastic lesions and the diagnosis for subtypes of high-grade glioma. Although tumor cells in radiation necrosis were detected with a high sensitivity, further investigation is necessary for clinical application in surgery for recurrent glioma.
authors.affiliation: Departments of Neurosurgery and.
authors.forename: Masayuki
authors.initials: M
authors.lastname: Kanamori
authors.forename: Atsuo
authors.initials: A
authors.lastname: Kikuchi
authors.forename: Mika
authors.initials: M
authors.lastname: Watanabe
authors.forename: Ichiyo
authors.initials: I
authors.lastname: Shibahara
authors.forename: Ryuta
authors.initials: R
authors.lastname: Saito
authors.forename: Yoji
authors.initials: Y
authors.lastname: Yamashita
authors.forename: Yukihiko
authors.initials: Y
authors.lastname: Sonoda
authors.forename: Toshihiro
authors.initials: T
authors.lastname: Kumabe
authors.forename: Shigeo
authors.initials: S
authors.lastname: Kure
authors.forename: Teiji
authors.initials: T
authors.lastname: Tominaga
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001932:Brain Neoplasms / Q000175:diagnosis / Q000235:genetics / Q000601:surgery*; D015342:DNA Probes; D003937:Diagnosis, Differential; D005240:Feasibility Studies; D005260:Female; D005910:Glioma / Q000175:diagnosis / Q000235:genetics / Q000601:surgery*; D006801:Humans; D007430:Intraoperative Care / Q000379:methods*; D007521:Isocitrate Dehydrogenase / Q000235:genetics*; D008297:Male; D008875:Middle Aged; D009154:Mutation; D016133:Polymerase Chain Reaction / Q000379:methods; D011237:Predictive Value of Tests; D011379:Prognosis; D012680:Sensitivity and Specificity; D055815:Young Adult
chemical_list: D015342:DNA Probes; C538784:IDH2 protein, human; D007521:Isocitrate Dehydrogenase; C543588:IDH1 protein, human
keywords: COLD = co-amplification at lower denaturation temperature; FMCA = fluorescence melting curve analysis; IDH = isocitrate dehydrogenase; IDH1; IDH2; PCR = polymerase chain reaction; Tc = denaturation temperature; Tm = melting temperature; glioma; intraoperative molecular diagnosis; oncology