Background Almost 1 in 6 malignant brain cancers are Glioblastoma Multiforme, relative to most other brain cancers it is the most aggressive and prevalent by the numbers.¹ Even with the best treatment options median Overall Survival(OS) remains morbid at 14.6 months and Progression Free Survival(PFS) remains 6.9 months.² Telomerase Reverse Transcriptase promoter mutations,³ Isocitrate Dehydrogenase(IDH) mutations,⁴ and Tumor Mutation Burden(TMB)⁵ are three prominent tumor markers that are known to be associated with better PFS and OS; markers like these in the presence of new therapies maybe prove crucial to the development of novel therapies. Immunotherapy has been dubbed a ‘game changer’ in certain hematological and solid malignancies. Specifically, PD1 is a glycoprotein that is a strong negative regulator of the immune system, by blocking this glycoprotein Anti-PD-1 agents harness a strong response by the immune system to fight a malignancy⁶. In conjunction with these new found tumor markers, Anti-PD-1 agents maybe the solution that could dramatically improve OS and PFS in these patients.

Methods The goal of this study was to retrospectively analyze patients‘ charts who had received Anti-PD-1 therapy and had TERT promoter mutations, IDH mutations, different TMBs, and other markers and to compare their OS and PFS outcomes with conventional therapies and their response to immunotherapy.

Results Upon analyzing the data the presence of a TERT promoter 124C>T mutation, IDH wildtype, and lower TMB gave much better OS and PFS after treatment in patients on Anti-PD1 therapy.

Conclusions Although this was a small study, these results certainly can be used to examine larger subsets of patients with these markers receiving immunotherapy because they had definitively better outcomes as compared to status quo treatment options.

Ethics Approval The study was approved by Washington University Ethics Board, approval number 201111001.

References

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