Stereotactic body radiotherapy versus non-SBRT radiotherapy for medically inoperable stage I non–small cell lung cancer in elderly patients: A systematic review and meta-analysis.

Abstract

e20038 Background: Elderly patients with medically inoperable stage I non–small cell lung cancer (NSCLC) are commonly treated with radiation therapy. While stereotactic body radiotherapy (SBRT) is widely used, its benefits compared with conventional and hypofractionated radiotherapy in this population remain debated. We performed a systematic review and meta-analysis to clarify differences in survival, disease control, and toxicity. Methods: Eight comparative studies were included. Outcomes assessed were overall survival (OS), progression-free survival (PFS), local control, patterns of failure, mortality, and severe toxicity. Pooled hazard ratios (HRs) and risk ratios (RRs) with 95% confidence intervals (CI) were calculated. Results: SBRT was associated with significantly improved overall survival (OS) compared with non-SBRT radiotherapy (HR 0.74, 95% CI 0.68–0.80; p<0.00001; I²=20%). No significant OS difference was observed when SBRT was compared specifically with conventional radiotherapy (HR 1.06, 95% CI 0.79–1.42). Time-specific analyses demonstrated no OS difference at 1 year; however, SBRT improved 2-year OS (RR 1.24, 95% CI 1.02–3.41), primarily when compared with conventional radiotherapy. Progression-free survival at 2 years was similar between groups. SBRT significantly improved local tumor control at 1–3 years, with the greatest benefit at 2 years (RR 1.23, 95% CI 1.09–1.38), and reduced local failure at 2 years (RR 0.33, 95% CI 0.24–0.46) and 3 years (RR 0.47, 95% CI 0.34–0.66). SBRT significantly reduced lung cancer–specific mortality compared with conventional radiotherapy (RR 0.47, 95% CI 0.24–0.93), but not when compared with hypofractionated radiotherapy. Severe overall and pulmonary toxicities were low and comparable between SBRT and non-SBRT treatments. Conclusions: In elderly patients with medically inoperable stage I NSCLC, SBRT offers meaningful improvements in survival and local tumor control compared with conventional radiotherapy, without added toxicity. Outcomes are similar between SBRT and hypofractionated radiotherapy, highlighting the importance of modern dose-delivery strategies in this population.