Neutrophil-to-lymphocyte ratio as a prognostic factor in patients with castration-resistant prostate cancer treated with docetaxel-based chemotherapy: a meta-analysis.

Background: In recent years, many studies have illustrated that the neutrophil-to-lymphocyte ratio (NLR) is a prognostic factor of metastatic castration-resistant prostate cancer (mCRPC), but their conclusions are controversial. The aim of this study was to assess the prognostic value of the NLR in patients with mCRPC treated with docetaxel-based chemotherapy.

Methods: Database searches were conducted in PubMed, EMBASE and the Cochrane Library to retrieve relevant published English-language literature up to 20 February 2023. RevMan 5.4.1 was used to summarize the hazard ratio (HR) and its 95% confidence interval (CI) for overall survival (OS) and progression-free survival (PFS) with subgroup analysis. Finally, Stata software was adopted for sensitivity analysis, and Egger's test was used to calculate the results of stability to determine whether there was publication bias.

Results: A total of 1,983 mCRPC patients from 14 retrospective cohort studies were included in this meta-analysis. The combined results showed that elevated NLR was significantly associated with worse OS (HR = 1.86, 95% CI: 1.55-2.23, P < 0.00001) and PFS (HR = 1.96 (95% CI: 1.52-2.53), P < 0.00001) in patients with mCRPC treated with docetaxel-based therapy. For subgroup analysis of high NLR, studies performed in Asia and cutoff value > 3 were associated with poorer OS, while cutoff values > 3 were associated with poorer PFS.

Conclusion: Our results suggest that the neutrophil-to-lymphocyte ratio may be a prognostic factor in patients with mCPRC with docetaxel-based chemotherapy.