10195- MPC-19 CURRENT STATUS OF MULTICENTER STUDIES USING GLIOMA TAILORED CUSTOM DNA/RNA PANELS

Abstract INTRODUCTION In 2018, we developed a glioma specific next-generation sequencing NGS panel and analyzed over 500 cases. In April 2023, we have expanded our work to include a custom DNA/RNA panel capable of detecting fusion genes. A multicenter collaborative study utilizing this advanced panel has been in progress since October 2023. This report outlines the diagnostic and screening significance of our panel and provides an update on the ongoing multicenter study. METHODS The custom gene panel included a 51 gene DNA and 37 gene RNA panel. DNA and RNA were extracted from formalin fixed paraffin embedded specimens used for histopathological diagnosis. Mutations, copy number and fusion genes were detected using the Illumina NextSeq1000. A multicenter collaborative study is currently underway with 21 institutions, analyzing cases at 43,000 yen each. This system has analyzed 210 consecutive brain tumors cases. RESULTS Currently, 12 of the 21 facilities have contracted us for analysis. The average analysis time was 35 days. Of the 210 cases, 35 (16.7%) harbored fusion genes. Nineteen cases (9.0%) had therapeutic target genes, including NTRK1/2, FGFR1/3, MET, and BRAF fusion genes. Eighteen of 112 GBM cases (16.1%) harbored fusion genes. Among receptors tyrosine kinases, EGFR gene alterations were observed in 42% of GBMs, often with EGFR amplification in cases with EGFR fusion or variants. PDGFRA gene alterations were present in 18%. Additionally, 9.8% of the GBMs had FGFR gene alterations, with FGFR1 mutation confined to the kinase domain and FGFR3 exclusively showing fusion genes. No FGFR2 alterations were detected. DNA analysis revealed that 11 cases were molecular GBMs, TERTp mutations were found in nine cases. CONCLUSION Our system’s analysis aligns with the WHO 2021 brain tumor classification, demonstrating its value as a screening tool in genomic medicine.