Effectiveness of lomustine and bevacizumab in progressive glioblastoma: a meta-analysis

BACKGROUND: Glioblastomas (GBMs) are the most aggressive type of glial brain tumors. Despite aggressive treatment with surgery and chemoradiation, GBMs invariably relapse and tumors are progressive. Controversy remains on optimal treatment of patients with recurrent GBMs. Data from previous trials have suggested that the addition of bevacizumab (BEV) to lomustine (CCNU) might improve overall survival (OS) as compared with that with monotherapies. The aim of this study was to compare the efficacy of BEV in addition to CCNU versus single-agent therapy in patients with recurrent GBM. METHODS: Electronic databases were searched for eligible literature updated in December 2017. Trials assessing the effectiveness of CCNU and BEV in progressive GBM were included, of which the main outcomes were progression-free survival (PFS) and OS. All the data were pooled with the corresponding 95% confidence intervals (CIs) using RevMan software. Sensitivity and heterogeneity were quantitatively evaluated. RESULTS: Three randomized clinical trials were identified, including 574 patients (combination group: 358, monotherapies group: 216). The combination group treated with BEV and CCNU showed improvement in PFS (OR = 0.49; 95% CI, 0.41–0.59; p < 0.00001). No significant differences were, however, found in patients in terms of the OS (OR = 0.84; 95% CI, 0.68–1.03; p = 0.09). CONCLUSION: Although treatment with CCNU plus BEV prolonged PFS, it did not confer OS advantage over monotherapies in patients with progressive GBM. The encouraging results of the addition of CCNU to BEV warrant investigation in further randomized trials.