Real-World Evidence on the Management and Outcomes of Glioblastoma in Elderly Patients: A Monocentric Retrospective Analysis

Background: Glioblastoma (GBM) carries a poor prognosis, and elderly or frail patients are often underrepresented in randomized trials. This study evaluated real-world outcomes and prognostic factors in a monocentric cohort of elderly GBM patients. Methods: We retrospectively analyzed 67 patients aged ≥ 65 years with histologically confirmed GBM treated between 2014 and 2023 at a single institution. Overall survival (OS) was defined as the primary endpoint, and progression-free survival (PFS) as the secondary endpoint. Univariable and multivariable Cox proportional hazards regression models were applied to assess prognostic factors, including age, sex, Karnofsky Performance Status (KPS), extent of resection, and temozolomide (TMZ) administration. Sensitivity analyses included proportional hazards testing using Schoenfeld residuals. Results: The median OS was 7.0 months (interquartile range [IQR] 5.5–13.0), and the median PFS was 5.0 months (IQR 3.6–7.9). In multivariable analyses, increasing age was independently associated with worse OS (HR 1.07, 95% CI 1.00–1.14, p = 0.043) and PFS (HR 1.06, 95% CI 1.00–1.13, p = 0.038). Female sex was independently associated with improved OS (HR 0.50, 95% CI 0.26–0.98, p = 0.044) and PFS (HR 0.41, 95% CI 0.21–0.80, p = 0.009). Higher KPS was significantly associated with better OS (HR 0.98, 95% CI 0.96–1.00, p = 0.064) and PFS (HR 0.98, 95% CI 0.95–1.00, p = 0.024). Omission of TMZ predicted inferior OS (HR 2.41, 95% CI 1.24–4.66, p = 0.009) and PFS (HR 2.31, 95% CI 1.20–4.46, p = 0.013). Total resection was independently associated with improved OS (HR 0.50, 95% CI 0.26–0.96, p = 0.037), while showing a non-significant trend for PFS (HR 0.62, 95% CI 0.33–1.17, p = 0.14). Sensitivity analyses confirmed the robustness of the models, with no relevant violations of the proportional hazards assumption (global p = 0.164 for OS; p = 0.086 for PFS). Conclusions: In this real-world cohort of elderly GBM patients, survival outcomes remained poor despite multimodal therapy. Independent predictors of improved outcomes included younger age, female sex, higher performance status, total resection, and temozolomide therapy. Sensitivity analyses confirmed the robustness of the models, underscoring the prognostic relevance of established clinical and treatment-related factors and highlighting the need for individualized treatment approaches in this vulnerable population.