Abstract

Introduction: EPSILoN (ECOG-PS, smoking, liver metastases, lactate dehydrogenase (LDH) and neutrophil-to-lymphocyte ratio (NLR)) is a potential prognostic score in metastatic NSCLC treated with immunotherapy (IT) in =2-line.

Aim: To assess overall survival (OS) and progression-free survival (PFS) in metastatic NSCLC treated with IT in =2-line based on EPSILoN score.

Methods: Retrospective analysis of patients with stage IV NSCLC treated with IT in =2-line. Each parameter of the score counts 1 point. Patients were stratified into 3 groups: best, intermediate and poor prognosis. Kaplan Meier and log-rank test were used to calculate OS and PFS curves and to assess survival differences. Univariate and multivariable cox-regression-analysis were performed to identify factors associated with PFS and OS.

Results: During 4 years of follow-up, 153 patients with metastatic NSCLC (78.4% male) were analyzed. At baseline, patients had a median age of 66.8 years, 32.7% smoking status, 81.7% ECOG-PS 0-1, 64.7% adenocarcinoma, 52.6% stage-IVB and 45.8% PD-L1=1%. Based on EPSILoN score, we identified 3 groups: best (25.5%), intermediate (63.4%) and poor (11.1%) prognosis. The median OS was 8.0 months with differences between prognostic groups (p=0.001). The multivariate analysis showed that NLR=4 (p=0.001), LDH=400 (p=0.029) and ECOG-PS=2 (p=0.050) were significantly associated with worse OS. The median PFS was 2.0 months, and the survival curves were also statistically different between groups (p=0.03).

Discussion: The EPSILoN score allowed the identification of 3 prognostic groups with different outcomes. Thus, this score is an important and easy-to-use tool to assess which patients will benefit the most from IT.