Adjuvant Systemic Therapy in Patients With Early-Stage NSCLC Treated With Stereotactic Body Radiation Therapy

Abstract Introduction Stereotactic body radiation therapy (SBRT) is commonly used to treat nonsurgical patients with early-stage NSCLC. There are no prospective data on the role of adjuvant chemotherapy in this setting. Methods Patients (≥18 years) diagnosed with clinical stages I-II NSCLC from 2004 to 2013 were identified using the National Cancer Database (n = 11,836). The Kaplan-Meier method was used to estimate overall survival (OS) distributions and the log-rank test was used to compare distributions by treatment strategy. Clinical stages I and II were subdivided according to the TNM staging and log-rank tests was used to compare survival distributions by treatment strategy within each subgroup. Results In patients with T2bN0, median OS in the SBRT alone and SBRT plus adjuvant chemotherapy groups were 16.5 months versus 24.2 months, respectively (95% confidence interval [CI]: 14.1–20.1 months and 18.8–33.3 months, respectively; p p p p Conclusions SBRT followed by adjuvant chemotherapy was associated with improved OS in comparison with SBRT alone in patients with T greater than or equal to 4 cm, similar to that seen after surgery.