Outcomes and Patterns of Care in Elderly Patients with Glioblastoma Multiforme

Background: Glioblastoma multiforme (GBM) is the most common primary malignant brain tumor in adults, with an increased incidence among the elderly. However, the optimal treatment strategy in elderly patients remains unclear. This study seeks to investigate the effect of patient selection and treatment strategies on survival trends in these patients. Methods: Patients with diagnosis codes specific for GBM were queried from the National Cancer Database during 2004–2016. Univariate and multivariate Cox regression analysis was performed to investigate outcomes. Survival curves and 5-year survival were also generated based on patient-specific factors. Results: Among 104,456 patients with GBM identified, elderly patients were less likely to receive radiotherapy (61.3% vs. 77.8%; P < 0.001) or chemotherapy (47.2% vs. 62.9%; P < 0.001) or to undergo surgical resection (68.3% vs. 81.8; P < 0.001). Mean overall survival was 9.1 months (standard deviation, 10.0) and 5-year survival was 5.3%. Multivariate analysis showed age 75–84 years (hazard ratio [HR], 1.39; 95% confidence interval [CI], 1.12–1.73; P = 0.003) and lower Karnofsky Performance Status (50–70: HR, 1.68, 95% CI, 1.35–2.08, P < 0.001; ≤40: HR, 1.79, 95% CI 1.18–2.72, P = 0.006) were associated with decreased overall survival, whereas surgical resection (subtotal resection: HR, 0.52, 95% CI, 0.38–0.71, P < 0.001; gross total resection: HR, 0.29, 95% CI, 0.21–0.41, P < 0.001), radiotherapy (HR, 0.65; 95% CI, 0.47–0.91; P = 0.012), and chemotherapy (HR, 0.65; 95% CI, 0.48–0.88; P = 0.006) were associated with increased overall survival in elderly patients. Conclusions: In an analysis of 104,456 patients with GBM, all treatment modalities were found to be used less frequently in elderly patients. Increasing age and poor performance status were associated with worsened survival. Gross total resection was associated with the greatest survival benefit, and chemotherapy and radiotherapy also improved survival outcomes. These treatment options improved outcomes regardless of performance status. Although maximal treatment strategies may improve survival in elderly patients with GBM, these treatment strategies must be balanced against patient-specific factors and quality-of-life concerns.