The Pretherapeutic Neutrophil-to-Lymphocyte Ratio for Docetaxel-Based Chemotherapy Is Useful for Predicting the Prognosis of Japanese Patients with Castration-Resistant Prostate Cancer

INTRODUCTION AND OBJECTIVES: The neutrophil-to-lymphocyte ratio (NLR) has been suggested as a simple marker of the systemic inflammatory response in critical care patients. The NLR can be easily calculated from routine complete blood counts in the peripheral blood. This parameter has been reported to be an independent prognosticator for some solid malignancies. In the present study, we examined the importance of the NLR as a prognostic marker for castration-resistant prostate cancer (CRPC) patients who received docetaxel- (DOC-) based chemotherapy. METHODS: We analyzed a total of 73 patients who received DOC chemotherapy for CRPC in Yokohama City University Medical Center and affiliated hospitals. Complete blood cell counts were performed, and the NLR was calculated using the neutrophil and lymphocyte counts obtained on the same day or a few days before the initiation of DOC chemotherapy. We determined the NLR cutoff value based on the sensitivity and specificity levels derived from area under the receiver operator characteristic curves for death. RESULTS: The median overall survival (OS) after DOC was 21.0 months (range: 2.0–51.0). The median OS was shorter in patients with a high NLR (≥2.59) than in those with a low NLR (<2.59) (12.0 versus 31.6 months, p=0.001). In the multivariate analysis, the NLR and lymph node (LN) metastasis were independent predictors of the OS (hazard ratio 3.643, p=0.001; hazard ratio 2.184, p=0.038, respectively). CONCLUSIONS: The higher NLR group showed a significantly poorer OS than the lower NLR group. Pre-DOC NLR might be a new marker for predicting the prognosis of patients who receive DOC chemotherapy.