NCOG-12. SURVIVAL OF THE ELDERLY: OUTCOMES OF VERY OLD GLIOBLASTOMA PATIENTS – RESULTS FROM AN AUSTRIAN MULTICENTER STUDY

Abstract

Abstract INTRODUCTION Glioblastoma (GBM) outcomes in very old patients remain understudied. Limited data exist on outcomes and treatment options for this specific population, necessitating further research. Materials and METHODS We retrospectively analyzed all elderly GBM patients ( >65 years), who underwent treatment at two Austrian academic centers from 2007 to 2021. We conducted a comparative analysis between patients aged 65-79 years (old cohort) and a cohort of patients aged over 80 years (very old cohort). RESULTS 387 patients were included, 43 of them over 80 years of age at the time of surgery. Median preoperative Karnofsky Performance Score (KPS) amounted to 80, median preoperative tumor volume was 26.44cm3. Among elderly patients 283 (75%) underwent resection and 61 (25%) only biopsy. 66.5% of the elderly cohort underwent adjuvant treatment following the EORTC protocol. 88 patients (25.6%) experienced preoperative seizures. Among the very old cohort 29 patients (67%) underwent resection and 14 (33%) biopsy only. 42.5% received adjuvant treatment, 5 patients (11.6%) presented with preoperative epilepsy. Mean PFS was 8.9 months in old patients and 8.4 months in very old patients. Kaplan Meier Analysis revealed a mean OS of 12.8 vs 10.7 months respectively. Elderly patients showed significantly better preoperative KPS (p=0.033) as well as higher preoperative tumor volumes (p=0.039). Old patients showed significantly higher incidences of both preoperative (p=0.043) and postoperative (p=0.032) epilepsy. Furthermore, old patients underwent significantly more often resection (p=0.020) and adjuvant therapy (p=0.009) compared to very old patients. However, survival analysis showed no statistic differences regarding PFS and OS between the two groups (p >0.05). CONCLUSION Despite preexisting unfavorable prognostic features, we could not find any significant differences between old and very old GBM patients. Hence, the treatment of glioblastoma in very old patients should adopt a more inclusive approach considering the patient's overall health status and comorbidities.