Correlation of Neutrophil to Lymphocyte Ratio and Absolute Neutrophil Count With Outcomes With PD-1 Axis Inhibitors in Patients With Advanced Non–Small-Cell Lung Cancer

Abstract Introduction Programmed death-1 (PD-1) axis inhibitors have become standard therapy in advanced non–small-cell lung cancer (NSCLC). Response might be delayed and pseudo-progression occasionally occurs in patients who eventually benefit from treatment. Additional markers beyond programmed death ligand 1 (PD-L1) expression are needed to assist in patient selection, response evaluation, and treatment decisions. Materials and Methods The relationship between prospectively collected clinical outcomes (response, disease control rate [DCR], treatment duration, overall survival) and hematologic parameters (neutrophil to lymphocyte ratio [NLR], absolute neutrophil count [ANC], and platelet to lymphocyte ratio [PLR]) was explored retrospectively in advanced NSCLC patients treated with PD-1 axis inhibitors at a major cancer center from May 2013 to August 2016. Hematologic parameters at baseline and during treatment (week 2 or 3 and week 8) were included. Results Of 88 patients treated with PD-1 axis inhibitors, 22 (25%) experienced partial response. Baseline NLR ≤4 was associated with superior DCR (74% vs. 50%; P  = .025), treatment duration ( P  = .037), time to progression ( P  = .053), and overall survival ( P  = .019), with no differential association according to PD-L1 tumor expression. Lower NLR and ANC during treatment were also associated with response to treatment ( P  = .025 and P  = .017, respectively), and treatment duration ( P  = .036 and P  = .008). No association was found between baseline PLR and DCR, response, treatment duration, nor overall survival. Conclusion Baseline NLR ≤4 and lower NLR and ANC during treatment might correlate with disease control and treatment response and should be explored further as potential predictors of treatment benefit in larger studies.