Survival of Primary Stereotactic Body Radiation Therapy Compared With Surgery for Operable Stage I/II Non-small Cell Lung Cancer.

Abstract

Stereotactic body radiation therapy (SBRT) is an accepted primary treatment option for inoperable early-stage non-small cell lung cancer (NSCLC). The role of SBRT in the treatment of operable disease remains unclear. We retrospectively evaluated patients with operable early-stage NSCLC who elected to receive primary SBRT, examined factors associated with SBRT, and compared overall survival after surgical resection and SBRT. The National Cancer Database was queried for patients with stage I/II, N0 NSCLC from 2004 to 2016. The proportion of patients who refused recommended surgery and were treated with SBRT was calculated. A propensity score predicting the probability of refusing surgery and receiving SBRT was generated and used to match SBRT and resected patients. Long-term overall survival was compared in the matched cohort using the Kaplan-Meier method and Cox regression. We identified 1359 patients (0.98%) who refused recommended surgery and elected SBRT. This proportion increased annually, from 0.1% in 2004 to 1.7% in 2016. Factors associated with SBRT were older age, black race, Medicaid coverage, lower T stage, and more recent diagnosis year. Propensity matching resulted in 1315 well-balanced pairs. Surgery was associated with higher median survival (74 vs 47 months, P < .01) in the matched cohort. Survival benefit persisted after adjusting for covariates on Cox regression (hazard ratio, 1.69; P < .01). Median survival was significantly higher after surgery compared with SBRT in a risk-adjusted matched cohort of patients judged to be surgical candidates. Operable patients considering primary SBRT should be educated regarding this difference in survival.