Outcomes and Treatment Algorithm in Glioblastoma Patients 80 Years and Older

Introduction: We investigate whether elderly patients benefit from the current standard of care for GBM including maximal safe resection.

Methods: Clinical, operative, radiographic, demographic, genetic, and outcomes data were retrospectively collected for patients treated for histologically confirmed WHO grade 4 GBM at UPMC from 2009 to 2020. Only patients 80-years old and older were included (n = 123). Of these patients, 105 patients had known IDH mutation status, of which all 105 patients were IDH wild type. Statistically significant values were set at p< 0.05.

Results: A univariate Cox proportional hazards analysis of GBM patients >80 years old identified the use of temozolomide, radiation, Karnofsky Performance Status (KPS) >70, and MGMT methylation with increased overall survival. Further multivariate Cox proportional hazards model analysis showed that the variables identified in the univariate analysis passed multicollinearity testing, and that use of temozolomide, KPS>70, and gross total resection were shown to significantly impact survival. Survival analysis showed that patients with biopsy alone had a shorter median overall survival (OS) compared to patients who received resection, temozolomide, and radiation (Log rank p-value < 0.0001, median OS 1.6 months vs. 7.5 months). Additionally, patients who underwent biopsy and then received temozolomide and radiation had a shorter median overall survival when compared to patients who received resection, temozolomide, and radiation (Log rank p-value 0.0047, median OS 3.6 months vs. 7.5 months).

Conclusion : For elderly patients with KPS >70, GTR followed by radiation and temozolomide is associated with maximum OS.