CNSC-63. THE COMPLEX RELATIONSHIP BETWEEN GENETIC ETIOLOGIES OF GLIOBLASTOMA AND PATIENT SURVIVAL: A RETROSPECTIVE ANALYSIS

Abstract Data Analysis was done using the NIH GDC Data Portal with glioblastomas being the only selected primary diagnosis (n=1381). Kaplan Meier plots were generated for various genes and mutations and the survival data was compared between carriers and non-carriers. Median survival was 14 months post diagnosis when all patients are clustered together. Survival Plot of patients with IDH1 R132H mutation (n=35) vs without IDH1 R132H mutation (n=538) reveals that carriers have longer survival compared to non-carriers. The next seven cases with the highest number of specific mutations were a variation between TP53 and EGFR, both genes implicated in various cancers due to their roles in cancer suppression and proliferation respectively. The ten most frequent specific mutations observed were all missense mutations. Furthermore, patients without PTEN mutations (n=98) had better survival compared to patients who had PTEN mutations (n=623), particularly observed after one year. For specific mutations, IDH1 R132H was detected in 35 patients. All other specific mutation groups had less than 30 patients, therefore, a larger cohort would be beneficial in understanding the survival outcomes of various specific mutations. In terms of total number of mutations per gene, PTEN had the highest followed by TP53 and EGFR. In understanding the survival data, the best target for therapies can be narrowed, regardless of the increasingly evident polygenic pathology of glioblastoma.