Treatment of very elderly glioblastoma patients ≥ 75 years of age: whom to treat.

PURPOSE: The prognosis of patients ≥ 75 years suffering from glioblastoma is poor. Novel therapies are usually reserved for patients ≤ 70 years. In an aging population, treatment of very elderly patients remains a challenge. METHODS: Between 2010 and 2018, a total of 977 glioblastoma patients were treated at our institution. Of these, 143 patients were ≥ 75 years at diagnosis. Primary procedure was surgical resection or biopsy followed by adjuvant treatment, whenever possible. We retrospectively investigated overall survival (OS) and potential prognostic factors influencing survival, including Karnofsky Performance Status (KPS), surgical therapy, adjuvant therapy as well as MGMT promotor status. RESULTS: In very elderly patients, median age was 79 years (range: 75-110). Biopsy only was performed in 104 patients; resection was performed in 39 patients. Median OS for the entire cohort was 5.9 months. Univariate analysis showed that KPS at presentation (≥ 70 vs. ≤60), surgery vs. biopsy, adjuvant chemotherapy and adjuvant radiotherapy were significantly associated with OS (6 vs. 3, p < 0.0111; 12 vs. 4, p = 0.0011; 11 vs. 4, p = 0.0003 and 10 vs. 1.5 months, p < 0.0001, respectively). Multivariate analysis confirmed adjuvant radiotherapy (p < 0.0001) and chemotherapy (p = 0.0002) as independent factors influencing OS. CONCLUSION: For very elderly patients, the natural course of disease without treatment is devastating. These patients benefit from multimodal treatment including adjuvant radiotherapy and chemotherapy. A beneficial effect of resection has not been demonstrated. Treatment options and outcomes should be thoughtfully discussed before treatment decisions are made.