MMDA-08 EFFICACY OF STEREOTACTIC RADIOSURGERY PLUS NIVOLUMAB AND IPILIMUMAB IN MELANOMA BRAIN METASTASES: A META-ANALYSIS

Abstract

Melanoma brain metastases are a common and clinically significant complication, occurring in up to 40–50% of patients with advanced disease and historically associated with poor prognosis. The advent of immune checkpoint inhibitors, particularly the combination of nivolumab and ipilimumab, has improved systemic and intracranial outcomes; however, optimal intracranial disease control remains a challenge. Stereotactic radiosurgery (SRS) is an established local therapy that achieves high rates of lesion-specific control and may have synergistic effects with specific immunotherapy through immune modulation, yet its added clinical benefit when combined with dual checkpoint inhibition remains uncertain. This study aimed to evaluate the impact of SRS in combination with nivolumab and ipilimumab on outcomes in patients with melanoma brain metastases. A systematic review and meta-analysis were conducted using PubMed, EBSCO, and Cochrane databases to identify studies including adult patients treated with nivolumab plus ipilimumab with or without concurrent or upfront SRS. Time-to-event outcomes, including overall survival, local control, and distant intracranial control, were pooled using hazard ratios (HRs) with 95% confidence intervals under a random-effects model. The addition of SRS to immunotherapy was associated with improved local control (HR: 0.70; 95% CI: 0.17-2.89; I² = 85.4%), suggesting a reduction in intracranial progression at treated sites. However, no statistically significant improvement in overall survival was observed (HR: 0.98; 95% CI: 0.62-1.55; I² = 74.6%). Distant intracranial control showed variable results without a consistent advantage (HR: 0.85; 95% CI: 0.25-2.87; I² = 80.2%). Limitations include the retrospective design of most included studies, heterogeneity in treatment timing, and potential selection bias. In conclusion, SRS combined with nivolumab and ipilimumab improves intracranial control, particularly at the local level, without a clear survival benefit, supporting its role as part of a multidisciplinary treatment strategy.