Efficacy and safety of combined anti-vascular and two-staged stereotactic radiosurgery therapy for brain metastases with brainstem compression: a retrospective multicenter study  

Abstract

Stereotactic radiosurgery poses a significant risk when treating brain metastases in close proximity to the brainstem. To address this issue, a novel approach known as "combined anti-vascular therapy" has been devised for these metastases. This treatment regimen involves a one-week course of two-staged stereotactic radiosurgery (2-SSRS), supplemented with the administration of the anti-vascular agent bevacizumab during the radiosurgery interval. The objective of this study is to assess the efficacy and safety of a combined anti-vascular and two-staged stereotactic radiosurgery therapy for brain metastases with brainstem compression. A retrospective analysis was conducted on patients treated at five gamma knife treatment centers to assess changes in tumor size and peritumoral edema volume. Clinical symptom changes were evaluated using the Headache Scale (VAS), Dizziness Disorder Inventory (DHI), Vomiting Scale (VS), and Glasgow Coma Scale (GCS). The Karnofsky Task Scale (KPS) and Barthel Index (BI) were used to assess overall physical fitness and physical activity rehabilitation. Tumor local control (TLC) and overall survival (OS) rate were also calculated for the patients. Among the 36 patients with brain metastases with brainstem compression, 36 received combined anti-vascular therapy. Both edema volume and tumor volume significantly decreased during the treatment period and post-treatment 3 months (p < 0.01). Clinical symptoms, as indicated by median scores of VAS, DHI, VS, and GCS, showed significant improvement during treatment and at the 3-month follow-up (p < 0.01). Median changes in KPS and BI, reflecting overall physical fitness and physical activity rehabilitation, were also similar and statistically significant (p < 0.01). The patient cohort exhibited a median overall survival of 14.2 months, with corresponding 6-month and 12-month survival rates of 91.7% and 80.0%, respectively. Tumor local control rates at 6 and 12 months were 94.7% and 78.9%, respectively.The combination of anti-vascular therapy with 2-SSRS demonstrates safety and efficacy in treating patients with brain metastases with brainstem compression. This approach rapidly alleviates patient symptoms, effectively manages tumor progression, extends overall survival, and exhibits manageable adverse effects.