Role of Neutrophil to Lymphocyte Ratio and Platelet to Lymphocyte Ratio in Predicting the Response to First Line Chemotherapy in Colorectal Cancer Patients with Synchronous Liver Metastases: A Retrospective Study

Background: There is some evidence that high level of neutrophil to lymphocyte ratio (NLR) and platelet to lymphocyte ratio (PLR) is associated with poor survival in several malignancies including colorectal cancer (CRC); however data on the significance of these markers to predict response to systemic therapy is limited. Objectives: The aim of this study was to assess the role of pretreatment NLR and PLR in predicting response to first line chemotherapy in CRC patients with synchronous metastases. Methods: Clinical records of 81 CRC patients with synchronous liver metastases, who underwent upfront chemotherapy, were included in this retrospective study. The optimal cut of value for NLR and PLR was determined according to receiver operating characteristic (ROC) curve analysis. Correlation between response to chemotherapy and NLR or PLR was evaluated. Results: The optimal cut off for NLR and PLR was 2.666 and 182.589, respectively. Patients with low NLR had significantly higher objective response (complete response + partial response) compared to patients with high NLR (54.3% versus 13%, respectively, P: < 0.001). In patients with low PLR, 41.2% had objective response compared to 13.3% of patients with high PLR (P = 0.012). The univariate analysis determined that, both NLR and PLR are significantly associated with better objective response, but in multivariate analysis, only NLR was identified asan independent predictive marker of response [odds ratio = 4.55; P = 0.013]. Conclusions: Results of this study indicate that, measuring NLR might provide us an inexpensive method to predict response to first-line chemotherapy in CRC patients with synchronous liver metastases.