Meta-analysis of bevacizumab therapy in recurrent glioblastoma multiforme shows associations with improved outcomes

BACKGROUND: Glioblastoma multiforme (GBM) poses significant challenges in oncology, with limited treatment options and poor prognosis. Despite advancements, recurrence remains common, emphasizing the need for effective therapeutic strategies. This meta-analysis comprehensively evaluates the efficacy and safety of treatments like bevacizumab (BEV), temozolomide (TMZ), and lomustine (CCNU) for recurrent GBM (rGBM), aiming to identify optimal approaches and guide clinical decisions. METHODS: Following Preferred Reporting Standards for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, a systematic review was conducted, and randomized controlled trials assessing interventions for rGBM were included. The Cochrane risk-of-bias assessment was used to evaluate study quality. Primary outcomes included progression-free survival (PFS) and overall survival (OS), whereas adverse events were assessed as secondary outcomes. RESULTS: Nine articles met the inclusion criteria, comprising a total of 1689 participants. BEV therapy outperformed pre-BEV treatment across several parameters, including full resection (odds ratio [OR] = 14.50, 95% confidence intervals [CI]: 1.82-115.29, p = 0.01) and biopsy outcomes (OR = 18.67, 95% CI: 2.55-136.41, p = 0.04). BEV also demonstrated higher rates of MGMT promoter methylation at baseline (OR = 11.84, 95% CI: 1.87-74.77, p = 0.009), as well as associations with improved PFS (OR = 1.16, 95% CI: 0.10-2.22, p = 0.03) and OS (OR = 0.63, 95% CI: 0.01-1.26, p = 0.05) compared to pre-BEV therapies. BEV monotherapy was associated with more favorable outcomes than combination therapies, with a pooled OR of 19.50 (95% CI: 2.69-141.35, p = 0.03) for corticosteroid use. Adverse event analysis revealed a lower incidence of CNS hemorrhage with standard therapy. TMZ outperformed the TMZ + CCNU combination in PFS (OR = 2.44, 95% CI: 1.23-4.83, p = 0.01), OS, and MGMT methylation (OR = 2.58, 95% CI: 1.40-4.78, p = 0.002). CONCLUSION: BEV monotherapy emerges as a promising treatment for rGBM, with favorable outcomes in biopsy results, corticosteroid use, PFS, and OS. Future research is needed to confirm these findings and optimize BEV's clinical application, emphasizing tailored treatment strategies to improve patient prognosis.