10257- GEN-15 CURRENT STATUS AND UTILITY OF CANCER GENE PANEL TESTING

Abstract In recent years, cancer gene panel testing has been covered by insurance, and its utility has been reported. At our institution, in addition to the insurance-covered cancer gene panel test, we have conducted the PleSSision-Rapid test, which can measure 156 genes, on various tumors as part of clinical research. The insurance-covered panel test was conducted in 37 cases, 86% of which were gliomas. Gene abnormalities leading to therapeutic drugs were identified in 5 cases (TMB high: 3 cases, NTRK2 fusion gene: 1 case, FGFR1: 1 case). On the other hand, in the clinical research panel testing, analysis was performed on 142 cases, including 54 cases of glioma, 49 cases of meningioma, and 16 cases of metastatic brain tumors. The clinical research panel test serves three main purposes: (1) diagnostic assistance, (2) screening before insurance-covered panel testing, and (3) research based on genetic analysis. For diagnostic assistance, it is possible to evaluate genes such as IDH1/2, TP53, ATRX, TERT promoter, and CDKN2A. In screening, in 11 cases where both tests were performed, mutations such as TMB high and FGFR1, identified in the insurance-covered panel, could also be detected. In research, frequent mutations in glioblastoma, including TERT promoter, KDM6, RB1, PTEN, as well as copy number variations in PTEN, CDKN2A, RB1, CHK2, and SMO, were confirmed. In oligodendroglioma, mutations in ERBB4 and KDM6A, in addition to IDH1 and TERT promoter, were observed. In meningiomas, a higher frequency of NF2 and KDM6A mutations was observed in Grade 2/3 compared to Grade 1, as well as a significantly higher frequency of copy number abnormalities in genes related to DNA repair, histone modification, and chromatin remodeling. Based on these findings, we are working on the development of new therapies.