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

Abstract

Background: 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.

Methods: 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.

Results: 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).

Conclusions: 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.