Neutrophile-to-lymphocyte, lymphocyte-to-monocyte, and platelet-to-lymphocyte ratios as prognostic and response biomarkers for resectable locally advanced gastric cancer

Background: Perioperative fluorouracil plus leucovorin, oxaliplatin, and docetaxel (FLOT) improves prognosis in locally advanced gastric cancer (LAGC). Neutrophil-to-lymphocyte (NLR), lymphocyte-to-monocyte (LMR), and platelet-to-lymphocyte (PLR) ratios are prognostic biomarkers but not predictive factors.

Aim: To assess blood ratios' (NLR, LMR and PLR) potential predictive response to FLOT and survival outcomes in resectable LAGC patients.

Methods: This was a multicentric retrospective study investigating the clinical potential of NLR, LMR, and PLR in resectable LAGC patients, treated with at least one preoperative FLOT cycle, from 12 Portuguese hospitals. Means were compared through non-parametric Mann-Whitney tests. Receiver operating characteristic curve analysis defined the cut-off values as: High PLR > 141 for progression and > 144 for mortality; high LMR > 3.56 for T stage regression (TSR). Poisson and Cox regression models the calculated relative risks/hazard ratios, using NLR, pathologic complete response, TSR, and tumor regression grade (TRG) as independent variables, and overall survival (OS) as the dependent variable.

Results: This study included 295 patients (mean age, 63.7 years; 59.7% males). NLR was correlated with survival time (r = 0.143, P = 0.014). PLR was associated with systemic progression during FLOT (P = 0.022) and mortality (P = 0.013), with high PLR patients having a 2.2-times higher risk of progression [95% confidence interval (CI): 0.89-5.26] and 1.5-times higher risk of mortality (95%CI: 0.92-2.55). LMR was associated with TSR, and high LMR patients had a 1.4-times higher risk of achieving TSR (95%CI: 1.01-1.99). OS benefit was found with TSR (P = 0.015) and partial/complete TRG (P < 0.001). Patients without TSR and with no evidence of pathological response had 2.1-times (95%CI: 1.14-3.96) and 2.8-times (95%CI: 1.6-5) higher risk of death.

Conclusion: Higher NLR is correlated with longer survival time. High LMR patients have a higher risk of decreasing T stage, whereas high PLR patients have higher odds of progressing under FLOT and dying. Patients with TSR and a pathological response have better OS and lower risk of dying.