Neutrophil‐To‐Lymphocyte Ratio and Survival in Pembrolizumab‐Treated Oropharyngeal Cancer

Background A minority of patients receiving immunotherapy for oropharyngeal head and neck squamous cell carcinoma benefit. Finding biomarkers that predict response to ICI is important for improving outcomes in these patients. In this study, we determine the relationship between pretreatment neutrophil‐to‐lymphocyte ratio (NLR) and 6‐month progression‐free survival (PFS)/2‐year overall survival (OS) among patients with recurrent or metastatic (R/M) oropharyngeal cancer on pembrolizumab. Methods This study was a retrospective cohort study of patients with recurrent/metastatic OPSCC who were treated with pembrolizumab between May 2016 and May 2022 at a tertiary care academic center. The primary outcome was 6‐month progression‐free survival. The secondary outcome was 2‐year overall survival. NLR was treated as a continuous and dichotomous variable. Disease progression was determined using radiographic criteria adopted from the Response Evaluation Criteria in Solid Tumors. Results Sixty‐four patients with OPSCC were included. The median pre‐treatment NLR was 5.1 (IQR 3.1–8.3). Thirty‐seven (58%) patients had distant metastases at the start of ICI. When treated as a continuous variable, higher pretreatment NLR was associated with poorer 6‐month PFS [HR 1.14 (1.03, 1.27), p = 0.016] and 2‐year OS [HR 1.21 (1.09, 1.35), p = 0.001] for patients on pembrolizumab. Subgroup analyzes on patients who were p16+ versus p16‐ revealed that NLR was only associated with poorer survival for p16+ patients [HR 1.16 (1.00, 1.33), p = 0.046 versus HR 1.11 (0.94, 1.31), p = 0.203, respectively]. Conclusion Higher pretreatment NLR was associated with poorer 6‐month PFS and 2‐year OS in OPSCC patients treated with pembrolizumab. When stratified by p16 status, this association only remained significant among p16+ patients.