Efficacy and prognostic factors of stereotactic radiosurgery versus whole-brain radiotherapy for brain metastases in small cell lung cancer: a systematic review and meta-analysis

Abstract Objective To systematically evaluate the efficacy differences between stereotactic radiosurgery (SRS) and whole-brain radiotherapy (WBRT) in treating brain metastases from small cell lung cancer (SCLC), and to analyze key factors affecting patient prognosis, providing evidence-based support for developing individualized clinical treatment plans. Methods Strictly following PRISMA guidelines and registered on the PROSPERO platform (CRD420251147208), we systematically searched PubMed, Embase, Cochrane Library, and Web of Science databases for relevant literature from their inception to August 2025. Meta-analysis was performed using R software. The stability of results and publication bias were assessed through sensitivity analysis and funnel plots. Results 10 retrospective studies were included, involving 41,240 patients. Compared with WBRT, SRS significantly prolonged overall survival (HR = 0.74). Prognostic factor analysis showed that ECOG score 0–1 (HR = 0.61), female gender (HR = 0.89), receiving chemotherapy (HR = 0.37) or immunotherapy (HR = 0.69) were associated with better survival, while > 4 brain metastases (HR = 1.78), extracranial metastases (HR = 1.46), and age > 65 years (HR = 1.34) were poor prognostic factors. Sensitivity analysis indicated robust results, and funnel plot indicated no significant publishing bias. Conclusion In patients with SCLC brain metastases, SRS was associated with improved overall survival compared with WBRT, with particularly notable advantages in younger patients with good physical condition, limited intracranial lesions, and well-controlled systemic disease.