Timing of bevacizumab administration after biopsy for unresectable newly diagnosed glioblastoma.

Background: Recent studies have revealed that bevacizumab (BEV) can improve the survival of patients with newly diagnosed unresectable glioblastoma (GBM) with poor performance status. For patients who develop early clinical deterioration, early initiation of BEV would be beneficial. However, the safety and feasibility of early initiation of BEV remain to be determined because of the lack of studies addressing adverse events associated with BEV initiation <28 days after surgery. The aim of this study was to analyze the risks and benefits of early BEV administration after biopsy in patients with newly diagnosed GBM. Methods: Thirty-one consecutive patients with newly diagnosed GBM who underwent biopsy followed by BEV administration were investigated. The relationships between the timing of BEV administration and treatment response, survival outcome, and adverse events were analyzed. Results: Response rates based on the RANO criteria and overall survival times were similar between the early and standard BEV groups. No wound dehiscence was observed in the early BEV group, and only one case was observed in the standard BEV group. Patients in the early BEV group were more likely to have undergone biopsy with a smaller skin incision than those in the standard BEV group. Equivalent treatment effects of BEV were achieved in patients who developed early clinical deterioration and those without clinical deterioration. Conclusion: Early BEV administration is effective in controlling early clinical deterioration and does not increase the risk of wound-healing complications. Further studies with larger numbers of patients are needed to validate our results.