Stereotactic body radiotherapy versus surgery for early-stage non-small cell lung cancer: an updated meta-analysis involving 29,511 patients included in comparative studies

Objective: To evaluate the efficacy of stereotactic body radiotherapy (SBRT) versus surgery for early-stage non-small cell lung cancer (NSCLC) by means of a meta-analysis of comparative studies. Methods: Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses and Meta-analysis of Observational Studies in Epidemiology guidelines, searches were performed on PubMed, MEDLINE, Embase, and Cochrane Library for eligible studies. The meta-analysis compared the hazard ratios (HR) for overall survival (OS), cancer-specific survival (CSS), and local control (LC). Subgroup and meta-regression analyses evaluated the association of extent of surgical resection, study publication year, tumor staging, propensity score matching, proportion of chemotherapy use, and proportion of pathological lymph node involvement with CSS and OS. Results: Thirty studies involving 29,511 patients were included (surgery group: 17,146 patients and SBRT group: 12,365 patients). There was a significant difference in favor of surgery vs. SBRT in the 3-year OS (HR = 1.35; 95% CI: 1.22-1.44; I-2 = 66%) and 3-year CSS (HR = 1.23; 95% CI: 1.09-1.37; 1 2 = 17%), but not in the 3-year LC (HR = 0.97; 95% CI: 0.93-1.08; I-2 = 19%). In the subgroup analysis for OS, no significant difference between surgery and SBRT groups was observed in the T1N0M0 subgroup (HR = 1.26; 95% CI: 0.95-1.68; I-2 = 0%). In subgroup analysts for CSS, no significant difference was detected between the sublobar resection subgroup and the SBRT group (HR = 1.21; 95% CI: 0.96-1.53; I-2 = 16%). Conclusions: Surgery generally resulted in better 3-year OS and CSS than did SBRT; however, publication bias and heterogeneity may have influenced these findings. In contrast, SBRT produced LC results similar to those of surgery regardless of the extent of surgical resection. These findings may have important clinical implications for patients with comorbidities, advanced age, poor pulmonary reserve, and other factors that may contraindicate surgery.