EPID-02. SURVIVAL BENEFIT OF GLIOBLASTOMA PATIENTS AFTER FDA APPROVAL OF BEVACIZUMAB, A POPULATION-BASED STUDY USING SEER, TCR, AND NCDB DATABASES

Abstract

The nationwide studies on survival change in GBM patients treated with bevacizumab (BEV) after Food and Drug Administration (FDA) approval in May 2009 were limited. We investigated the impacts of BEV on survival in general GBM patient population by conducting a retrospective study based on the Surveillance, Epidemiology, and End Results (SEER), Texas Cancer Registry Limited-Use datasets (TCR), and National Cancer Database (NCDB). The adult patients diagnosed with GBM between 2005 and 2013 were included from SEER (N=14827), TCR (N=2709), and NCDB (N=32731). Patients were categorized into two calendar periods based on date of GBM diagnosis: pre-BEV (2005–2008, P1), and post-BEV (2010–2013, P2). The association between calendar periods and GBM survival was analyzed in SEER, TCR, and NCDB separately, by applying the Kaplan-Meier method and Cox proportional hazards model. A significant increase in median overall survival (OS) was observed from P1 to P2 in SEER (P1: 10, P2: 11, months; P<0.001), TCR (P1: 9.97, P2: 12.00, months; P<0.001), and NCDB (P1: 10.71, P2: 12.25, months; P<0.001). One-year survival rate was remarkably increased during P2 in SEER (P1: 41.9%, P2: 45.4%; P<0.001) and NCDB (P1: 45.1%, P2: 50.8%; P<0.001). In NCDB, 2-year survival rate was improved by 23.1% after BEV approval (P1: 18.6%, P2: 22.9%, P<0.001). No significant change of 1-year and 2-year survival rate was detected between P1 and P2 in TCR. After controlling different sets of covariates, including demographics, clinical characteristics, and treatments in multivariate analysis, the risk of death was significantly reduced by 9%, 28%, and 11% in SEER, TCR, and NCDB, respectively. Comparison and validation analysis were performed in the combined dataset (SEER+TCR), and consistent results were observed. Therefore, the administrations of BEV for recurrent GBM after FDA approval may contribute to the improvement of OS, 1-year and 2-year survival rate in GBM patients.