Bevacizumab reduces peritumoral brain edema in lung cancer brain metastases after radiotherapy

Abstract

BackgroundThe aim of this study was to investigate the efficacy of bevacizumab (Bev) in reducing peritumoral brain edema (PTBE) after stereotactic radiotherapy (SRT) for lung cancer brain metastases.MethodsA retrospective analysis was conducted on 44 patients with lung cancer brain metastases (70 lesions) who were admitted to our oncology and Gamma Knife center from January 2020 to May 2022. All patients received intracranial SRT and had PTBE. Based on treatment with Bev, patients were categorized as SRT + Bev and SRT groups. Follow‐up head magnetic resonance imaging was performed to calculate PTBE and tumor volume changes. The edema index (EI) was used to assess the severity of PTBE. Additionally, the extent of tumor reduction and intracranial progression‐free survival (PFS) were compared between the two groups.ResultsThe SRT + Bev group showed a statistically significant difference in EI values before and after radiotherapy (p = 0.0115), with lower values observed after treatment, but there was no difference in the SRT group (p = 0.4008). There was a difference in the distribution of EI grades in the SRT + Bev group (p = 0.0186), with an increased proportion of patients at grades 1–2 after radiotherapy, while there was no difference in the SRT group (p > 0.9999). Both groups demonstrated a significant reduction in tumor volume after radiotherapy (p < 0.05), but there was no difference in tumor volume changes between the two groups (p = 0.4089). There was no difference in intracranial PFS between the two groups (p = 0.1541).ConclusionBevacizumab significantly reduces the severity of PTBE after radiotherapy for lung cancer. However, its impact on tumor volume reduction and intracranial PFS does not reach statistical significance.

Effectiveness and safety of the bevacizumab and erlotinib combination versus erlotinib alone in EGFR mutant metastatic non-small-cell lung cancer: systematic review and meta-analysis

“…Bevacizumab has demonstrated a significant clinical benefit in CNS tumors, highlighting its anti-edema effect. This effect is particularly relevant in the reduction of post-radiation brain edema, a common complication in patients with brain metastases ( 46 , 47 ); in addition, bevacizumab has shown a beneficial effect in the treatment of refractory brain edema with an efficacy rate of 84.74% ( 46 ). Bevacizumab improves vascular permeability and reduces fluid infiltration into brain tissue, which helps mitigate the adverse effects of edema and improves treatment efficacy ( 47 ).…”

“…This effect is particularly relevant in the reduction of post-radiation brain edema, a common complication in patients with brain metastases ( 46 , 47 ); in addition, bevacizumab has shown a beneficial effect in the treatment of refractory brain edema with an efficacy rate of 84.74% ( 46 ). Bevacizumab improves vascular permeability and reduces fluid infiltration into brain tissue, which helps mitigate the adverse effects of edema and improves treatment efficacy ( 47 ). This mechanism may explain the improvement in progression-free survival observed in patients with brain metastases following a combination treatment with erlotinib and bevacizumab.…”