Neutrophil to Lymphocyte Ratio as a Prognostic Factor in European Patients with Epidermal Growth Factor Receptor-Mutant Non-Small Cell Lung Cancer Treated with Tyrosine Kinase Inhibitors

Background: A high neutrophil to lymphocyte ratio (NLR) has been associated with adverse outcomes in non-small cell lung cancer (NSCLC). However, information on epidermal growth factor receptor (EGFR)-mutant advanced NSCLC is scarce, and most of the studies published have been conducted in Asian populations. We aimed to assess the influence of pretreatment NLR on progression-free survival (PFS) and overall survival (OS) in Western European patients treated with EGFR tyrosine kinase inhibitors (TKIs). Methods: A retrospective evaluation of 41 patients with EGFR-mutant advanced NSCLC treated with EGFR TKIs between June 2010 and May 2016 was carried out. The association between several prognostic factors including pretreatment NLR and survival was analyzed. Results: Median PFS and OS were 10.58 and 20.84 months, respectively. OS for patients with a high NLR was 7.4 months, compared to 24.6 months for patients with a low NLR (p = 0.0122). In multivariate analysis, poor performance status (ECOG PS ≥ 2) and presence of ≥ 3 metastatic locations were identified as significant independent prognostic factors for worse PFS. For OS, unfavorable prognostic factors were a high NLR and central nervous system metastasis at diagnosis. Conclusion: Pretreatment NLR is an independent prognostic factor for OS in Western European patients with EGFR-mutant NSCLC treated with EGFR TKIs.