MMDA-07 OVERALL SURVIVAL WITH IMMUNOTHERAPY PLUS STEREOTACTIC RADIOSURGERY VERSUS IMMUNOTHERAPY ALONE IN NSCLC BRAIN METASTASES: A META-ANALYSIS

Abstract

Lung cancer remains the most common malignancy worldwide, with non-small cell lung cancer (NSCLC) accounting for approximately 80–85% of cases, predominantly adenocarcinoma and squamous cell carcinoma. Brain metastases (BMs) are a frequent and harmful complication, occurring in approximately 10% of patients at initial diagnosis of advanced disease and developing in up to 15–33% of patients with stage III NSCLC following treatment. The presence of BMs is associated with poor prognosis and significant morbidity. Management of NSCLC BMs has traditionally relied on local therapies, including surgical resection and radiotherapy, with stereotactic radiosurgery (SRS) representing the standard approach for most patients due to its high local control and favorable toxicity profile. However, intracranial progression remains a major challenge. Immune checkpoint inhibitors (ICIs) have transformed the treatment landscape of advanced NSCLC and demonstrate intracranial activity, with emerging evidence suggesting a potential synergistic effect when combined with radiotherapy. We conducted a systematic review and meta-analysis to evaluate the impact of ICIs combined with SRS compared with SRS alone on overall survival (OS) in patients with NSCLC and brain metastases. A systematic search of PubMed, Cochrane Library, and EBSCO databases identified four eligible studies. Hazard ratios (HRs) for OS were extracted and pooled using a random-effects model. The combined analysis demonstrated that the addition of ICIs to SRS was associated with improved overall survival compared with SRS alone (pooled HR = 0.80, 95% CI 0.45–1.42; I²=70.7%) with moderate heterogeneity across studies. These findings suggest a survival benefit with combined modality treatment. In conclusion, the integration of ICIs with SRS may improve overall survival in patients with NSCLC and brain metastases, supporting the growing role of combined systemic and local therapies in this population; however, prospective studies are needed to further define optimal treatment strategies and sequencing.