Effect of temozolomide on survival in elderly patients with glioblastoma and impaired performance status: a propensity score-matching analysis

OBJECTIVE At present, there is no consensus regarding the standard treatment for glioblastoma (GBM) in elderly patients with impaired Karnofsky performance status (KPS) scores. This study aimed to determine the effects of temozolomide (TMZ) versus best supportive care (BSC) in this population. MATERIALS AND METHODS We conducted a retrospective observational study of patients aged ≥65 years with histologically confirmed GBM and KPS scores ≤70 who were treated at our institution between January 2006 and July 2014. Demographic data, treatments, and outcomes were evaluated. Univariate and multivariate analyses were performed to identify the independent prognostic factors of overall survival (OS) and progression-free survival (PFS). The impact of TMZ on survival was analyzed by the application of propensity score matching of clinicopathological factors among patients who received TMZ vs BSC. RESULTS There were 153 patients (86 men, 56.2%) in this study. The median patient age was 70 years (range: 65-83 years). The median KPS score was 60 (range: 30-70). Seventy-eight patients (51.0%) received TMZ, whereas 75 (49.0%) received BSC. Median OS and PFS were 6.0 and 4.5 months, respectively. Compared with BSC, TMZ was associated with improved OS (hazard ratio [HR]: 0.38, 95% CI: 0.17-0.70; P=0.002) and PFS (HR: 0.41, 95% CI: 0.21-0.76; P=0.003) after propensity score matching. Factors independently associated with OS were KPS score (HR: 2.11, 95% CI: 1.48-7.67; P=0.016), extent of resection (HR: 1.98, 95% CI: 1.45-5.14; P=0.026), and treatment group (HR: 0.49, 95% CI: 0.23-0.87; P=0.019). The most frequent toxicity in the TMZ group was myelosuppression. CONCLUSION Compared with BSC, TMZ increased survival with acceptable toxicity in elderly GBM patients with KPS scores ≤70.