OP29NEXT GENERATION SEQUENCING : A COMPREHENSIVE GENETIC TEST TO PROVIDE DIAGNOSTIC, PROGNOSTIC AND PREDICTIVE INFORMATION IN BRAIN TUMOUR SAMPLES

Abstract

INTRODUCTION: There are currently a wide range of different diagnostic genetic tests for gliomas including IDH1/2 testing and loss of heterozygosity (LOH) 1p and 19q. These tests aid diagnosis, classification and can inform therapy choices. Next Generation Sequencing (NGS) can be used to target multiple regions of the genome simultaneously and the diagnostic utility for NGS is well established in our laboratory for germline mutations. We carried out a proof of principle study to investigate the utility of this technology on FFPE glioma samples, with a view to combine existing genetic tests and expand the number of genes investigated. This panel approach will be key for future clinical trials and treatment with personalised therapies. METHOD: We designed a TruSeq Custom Amplicon NGS panel for the detection of mutations in 25 genes known to be mutated in gliomas or other solid tumours. SNPs were also targeted for LOH analysis. We tested 5 non-glioma solid tumour samples and 5 glioma samples with known genetic changes and 6 glioma samples with unknown genetics on the panel. RESULTS: All known mutations were successfully detected by this NGS panel. We were also able to detect LOH. We identified additional clinically significant mutations in genes including ATRX, BRAF, CIC, FUBP1, KRAS, PIK3CA and TP53. CONCLUSION: We have proved in principle that NGS can be successfully used to detect point mutations and LOH in FFPE glioma samples. Future work will improve the variant analysis pipeline, analyse gene copy number changes and detect gene fusion events.