Post treatment NLR is a predictor of response to immune checkpoint inhibitor therapy in patients with esophageal squamous cell carcinoma

BACKGROUND: In view of the fact that peripheral blood parameters have been reported as predictors of immunotherapy to various cancers, this study aimed to determine the predictors of response to anti-programmed death-1 (anti-PD-1) therapy in patients with esophageal squamous cell carcinoma (ESCC) from peripheral blood parameters. METHODS: A retrospective analysis was conducted to investigate the predictive value of peripheral blood parameters including neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), monocyte-to-lymphocyte ratio (MLR) and systemic immune-inflammation index (SII) in the response to anti-PD-1 antibody treatment. 119 ESCC patients receiving combined treatment including anti-PD-1 antibody were enrolled in this study. RESULTS: The median progression-free survival (PFS) of all ESCC patients was 3.73 months. PFS rate in ESCC patients with low NLR at 6 weeks post treatment was higher than patients with high NLR (HR = 2.097, 95% CI 0.996–4.417, P = 0.027). However, PFS rate in ESCC patients with low NLR at baseline (HR = 1.060, 95% CI 0.524–2.146, P = 0.869) or 3 weeks post treatment (HR = 1.293, 95% CI 0.628–2.663, P = 0.459) was comparable with high NLR. And no statistically different was found in PFS rate between low PLR and high PLR at baseline (HR = 0.786, 95% CI 0.389–1.589, P = 0.469), 3 weeks post treatment (HR = 0.767, 95% CI 0.379–1.552, P = 0.452) or 6 weeks post treatment (HR = 1.272, 95% CI 0.624–2.594, P = 0.488) in ESCC patients. PFS rate was also comparable between low MLR and high MLR at baseline (HR = 0.826, 95% CI 0.408–1.670, P = 0.587), 3 weeks post treatment (HR = 1.209, 95% CI 0.590–2.475, P = 0.580) or 6 weeks post treatment (HR = 1.199, 95% CI 0.586–2.454, P = 0.596). PFS rate was similar between patients with low SII and high SII at baseline (HR = 1.120, 95% CI 0.554–2.264, P = 0.749), 3 weeks post treatment (HR = 1.022, 95% CI 0.500–2.089, P = 0.951) and 6 weeks post treatment (HR = 1.759, 95% CI 0.851–3.635, P = 0.097). CONCLUSIONS: NLR at 6 weeks post treatment is a predictor of the response to anti-PD-1 treatment in patients with ESCC.