Chemotherapy for adults with malignant glioma: A systematic review and network meta-analysis

Abstract

Aim: Malignant glioma is the most common primary brain tumor in adults and the survival rate has remained very low. Thus, determining the optimal treatment for patients can be challenging. To compare the efficacy of common therapies, we performed network meta-analysis to estimate the efficacy and safety among procarbazine, lomustine, vincristine, temozolomide, bevacizumab plus temozolomide, and placebo for patients with malignant glioma. Material and Methods: Relevant studies (as of March, 2014) were identified by searching PubMed, Embase, and Central databases. The primary endpoint of the analysis was the overall survival (OS) and progression-free survival (PFS) of glioma patients. Results: Nine trials with a total of 3472 patients were included in our network meta-analyses. Compared with placebo, bevacizumab plus temozolomide was associated with the highest estimates of OS and PFS for 12 and 24 months (12 month OS odds ratio [OR]: 2.44; 95% credibility interval [CrIs]: 0.76-9.69; 24 month OS OR: 2.56; 95% CrIs: 1.12-5.24; 12 month PFS OR: 6.76; 95% CrIs: 2.80-17.34; 24 month PFS OR: 3.69; 95% CrIs: 0.62-28.63). However, bevacizumab plus temozolomide did not significantly improve OS or PFS compared to temozolomide alone. Conclusion: Bevacizumab plus temozolomide combination therapy is not significantly more effective than temozolomide alone in improving survival of glioma patients. Moreover, bevacizumab was associated with higher hematologic toxicities. Bevacizumab should be used with caution in glioma patients. Additional randomized controlled trials are required to confirm this finding.