Rapid and sensitive intraoperative detection of mutations in the isocitrate dehydrogenase 1 and 2 genes during surgery for glioma

Abstract

Object 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.

Rapid Intraoperative Molecular Characterization of Glioma

“…10 In accord, research techniques have applied real-time PCR detection of IDH1 mutation 11 or mass spectrometry to the intraoperative detection of 2-hydroxyglutarate, the metabolite of mutant IDH1 . 12 OperaGen was designed to simultaneously detect distinguishing genomic features in both the TERT promoter and IDH1 to sensitively identify diffuse glioma in an intraoperative timeframe.…”

Future directions of operative neuro-oncology

“…Published approaches include ambient mass spectroscopy based on defined tumor profiles [23,24], genotyping for know tumor mutations such as telomerase reverse transcriptase (TERT) promoter and isocitrate dehydrogenase 1 and 2 (IDH1, IDH2) [25,26], molecular analysis based on tumor core versus leading edge gene expression differences [27], and flow cytometry assessing cell proliferation densities [28]. These techniques have all shown promise for guiding surgical resections and improving intra-operative tumor characterization, but are largely in the proof-of-principle stage.…”

IDH-Mutant Gliomas

“…Moreover, T2-FLAIR mismatch sign was found as a highly specific imaging marker for IDH-mutant astrocytoma [112][113][114]. Intraoperative technologies to assess IDH1 mutation have also been established [115][116][117]. These advanced technologies may allow the development of tailored surgical strategies for IDH-mutant gliomas.…”