Guan Y, et al. - This study was undertaken to evaluate the prognostic value of the neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR) in metastatic castration-resistant prostate cancer (mCRPC) individuals and to evaluate the response of abiraterone or enzalutamide through applying NLR and PLR. Databases searching was carried in PubMed, EMBASE, Google Scholar, and the Cochrane Library for relevant published literature up to October 2019. Researchers conducted data extraction and quality evaluation on the eligible studies. The study consisted of 3,144 mCRPC individuals (from 15 cohort studies) in this meta-analysis. In mCRPC individuals, NLR and PLR were effective biomarkers for predicting prognosis and served as indicators of the efficacy of personalized treatment of mCRPC applying abiraterone or enzalutamide. Further, more randomized control trials (RCTs) are required in order to investigate the promising value of hematologic parameters.