Title: Prognostic factors for survival in locally advanced NSCLC treated with concurrent chemoradiation (CRT): An institutional analysis Background: CRT is the standard of care for patients with locally advanced non-small cell lung cancer (NSCLC). Analysis of prognostic factors in NSCLC has defined patient subsets with varying survival .There is limited data about these factors in patients treated with CRT. The purpose of this study is to explore factors predictive of survival in this patient population. Methods: In this retrospective study, data from patients with locally advanced NSCLC, treated with CRT at Stony Brook University Hospital from 2007 to 2015 were collected. Age, gender, histology, TNM stage and number of positive lymph node stations (PLNS) were evaluated as independent prognostic factors.3-year Kaplan-Meier survival curves were generated and log rank tests were used to evaluate the difference in survival between groups. Results: 134 patients were included in the study. 3-year overall survival (OS) was 24.6 %, which was comparable to estimates published in literature. Advanced stage and number of nodal stations significantly affected OS. 3-year OS for stage II, III and IV patients was 42.9%, 25.5 % and 0% (p = 0.006), respectively. Patients with less than 3 PLNS had improved OS outcomes compared to those with 3 or more PLNS (29.7% vs 18.3%, p = 0.019). Age, gender and histology did not significantly affect survival. Conclusions: TNM stage and number of PLNS have the greatest impact on survival in locally advanced NSCLC patients treated with CRT. Our study suggests that these factors should be included in risk stratification models in this patient population.

*5 patients were missing information on stage