Prognostic Value of Neutrophil to Lymphocyte Ratio in Patients Who Received Defintive Radiation Therapy for Head and Neck Squamous Cell Carcinoma

Abstract

With growing evidence on the role of inflammation in carcinogenesis, the presence of a systemic inflammatory response has been proposed as having prognostic significance in a wide range of cancers. The purpose of this study was to investigate the prognostic value of pre-treatment neutrophil/lymphocyte ratio (NLR) in head and neck squamous cell carcinoma (HNSCC) patients treated with definitive radiotherapy (RT). We retrospectively analyzed 498 patients with stage I-IVB HNSCC including oral cavity, nasopharyngeal, oropharyngeal, hypopharyngeal and laryngeal cancer who received definitive RT with (62.7%) or without (37.3%) chemotherapy between 2006 and 2015. The median age of all patients was 60 years. Patients with high NLR had more advanced stage (p<0.001) and they received induction or concurrent chemotherapy more frequently (76.2% vs. 52.5%, p <0.001). progression free survival (PFS) and overall survival (OS) were calculated by the Kaplan-Meier method and compared by the log-rank test. Cox’s regression model was used for multivariate analysis of selected variables (p<0.05 in univariate analysis) as prognostic factors. The median follow up time was 38 months and 5-year PFS and OS for all patients were 62.3% and 72.1%. With NLR >2.7 considered as high according to receiver operating characteristic curve using PFS as an endpoint, 172 patients had a high NLR. Patients with high NLR showed significantly higher regional failure rate (37.8% vs, 28.6%, p <0.001) while incidence of local and distant failure were comparable to those with low NLR. PFS and OS were significantly lower in high NLR patients (5-year PFS 39.7% vs. 74.8%; 5-year OS. 51.0% vs. 83.7%, p <0.001, respectively). In subgroup analysis according to subsite of HNSCC, patients with high NLR showed significantly better PFS and OS in oral cavity, nasopharyngeal, hypopharyngeal and laryngeal cancer as well, while difference between two groups showed borderline significance in oropharyngeal cancer. In multivariate analysis, high NLR still remained as a independent prognostic factor for PFS and OS (HR for PFS 2.863, 95% CI 1.755-4.670, p<0.001; HR for OS 2.863, 95% CI 1.755-4.670, p<0.001). The patients with high NLR showed poorer survival and different patterns of failure. The optimal therapeutic approaches should be considered for these patients.