Neutrophil-to-Lymphocyte Ratio (NLR) Predicts PD-1 Inhibitor Survival in Patients with Metastatic Gastric Cancer

Abstract

Background and Aims. Biomarkers for systemic inflammation have been introduced into clinical practice for risk-rating in cancer patients’ treatment. This study is aimed at confirming the prognostic role of the neutrophil-to-lymphocyte ratio (NLR) as an effective biomarker for patients with metastatic gastric cancer (MGC) receiving anti-PD-1 agents. Method. Patients with MGC who received anti-PD-1 treatment at the Chinese PLA General Hospital between January 2016 and November 2020 were reviewed. The study analyzed the association of NLR and overall survival (OS) or progression-free survival (PFS) and antitumor response rate with PD-1 inhibitors. Results. 137 patients were included in the final analysis. The area under the curve value of NLR for 6-month OS was 0.71. The best cut-off value for NLR was 3.23. $\text{NLR}<3.23$ was associated with longer OS ( $\text{HR}=0.38$ , 95% CI, 0.26-0.57, $p<0.001$ ) and PFS ( $\text{HR}=0.42$ , 95% CI, 0.29-0.62, $p<0.001$ ) in patients with MGC. No significant difference was observed in the objective response rate (ORR) (35.8% vs. 28.6%, $p=0.377$ ) and disease control rate (DCR) (86.4% vs. 78.6%, $p=0.229$ ) in the $\text{NLR}<3.23$ group and in the $\text{NLR}\ge 3.23$ group, respectively. Univariate analysis and multivariate analysis found that NLR was an independent prognosis biomarker for PFS and OS. Conclusions. Pretreatment elevated NLR was significantly associated with inferior PFS and OS in patients with MGC who received anti-PD-1 inhibitors. Clinicians need to consider patients with elevated NLR for decisions on immunotherapy strategy.