Mass spectrometry-based assay for the molecular diagnosis of glioma: concomitant detection of chromosome 1p/19q codeletion, and IDH1, IDH2, and TERT mutation status

The World Health Organization recently revised the diagnosis of glioma, to integrate molecular parameters, including IDH mutations and codeletion (loss of heterozygosity; LOH) of chromosome arms 1p/19q, into the definitions of adult glioma histological subtypes. Mutations in the TERT promoter may also be useful for glioma diagnosis and prognosis. The integration of molecular markers into routine diagnosis requires their rapid and reliable assessment. We propose a MassARRAY (MS)-based test that can identify 1p/19q codeletion using quantitative SNP genotyping and, simultaneously, characterize hotspot mutations in the IDH1, IDH2, and TERT genes in tumor DNA. We determined the reliability of the MS approach testing 50 gliomas and comparing the MS results with those obtained by standard methods, such as short tandem repeat genotyping, array comparative genomic hybridization (array-CGH) and Fluorescence In Situ Hybridization (FISH) for 1p/19q codeletion and Sanger sequencing for hotspots mutations. The results indicate that MS is suitable for the accurate, rapid, and cost-effective evaluation of chromosome deletions combined with hotspot mutation detection. This MS approach could be similarly exploited in evaluation of LOH in other situations of clinical and/or research importance.