The Role of Neutrophil-lymphocyte Ratio and Platelet-lymphocyte Ratio in Predicting Neoadjuvant Chemotherapy Response in Breast Cancer

Purpose: The role of the host immunologic environment is crucial in cancer progression. Recent studies revealed that neutrophil-lymphocyte ratio (NLR) and platelet-lymphocyte ratio (PLR), are possible surrogate markers of outcome in various cancers. In breast cancer, the therapeutic effect of neoadjuvant chemotherapy (NAC) differs in patients, and higher response rate reflects better outcomes. This study aimed to determine the predictive value of peripheral blood NLR and PLR for NAC response along with their prognostic role in breast cancer. Method: A total of 105 patients with breast cancer treated with NAC between 2009 and 2017 were analyzed retrospectively. NAC response and prognosis (disease-free-survival [DFS], progression-free-survival [PFS] and overall survival [OS]) according to NLR and PLR were evaluated. According to the optimal cut-off values for NAC response obtained from receiver operating characteristic (ROC) curves, patients satisfying both low NLR and PLR levels (low-ratio group) were compared to those who did not (high-ratio group). Results: The NLR cut-off value was <= 2.21 (area under the ROC curve [AUC], 0.617; 95% confidence interval [CI], 0.517-0.710; p= 0.030) with 94.1% sensitivity and 38.0% specificity. The PLR cut-off value was <= 143.36 (AUC, 0.618; 95% CI, 0.518-0.711; p = 0.040) with 85.3% sensitivity and 39.4% specificity. The low-ratio group demonstrated a better NAC response (p = 0.006) in multivariate analysis than the high-ratio group. The low-ratio group showed better DFS and PFS (p = 0.046 and p = 0.040, respectively) and longer OS (p = 0.078) in univariate survival analysis than the high-ratio group. In multivariate analysis, the low-ratio group had significantly better PFS (p = 0.049) and higher DFS (p = 0.054) than the high-ratio group. Conclusions: The combination of NLR and PLR showed improved prediction of NAC response, revealing their potential as screening tools, significant prognostic role in breast cancer patients who receive NAC. Further studies with subgroup analysis, larger population and longer follow up duration are required.