Prognostic significance of complete blood count parameters in castration-resistant prostate cancer patients treated with androgen receptor pathway inhibitors

Background: This study investigated the prognostic significance of complete blood count data in castration-resistant prostate cancer patients treated using androgen receptor pathway inhibitors (ARPIs). Patients and Methods: Patients treated with an ARPI, abiraterone or enzalutamide, as first-line therapy for castration-resistant prostate cancer from 2014 to 2018 were included. The association between complete blood count data and prognoses including progression-free survival and overall survival (OS) was investigated. Results: High white blood cell counts (<median vs. >= median; hazard ratio [HR], 1.82, 95% confidence interval [CI], 1.14-2.89; P = 0.012) and high neutrophil-to-lymphocyte ratios (<median vs. >= median; HR, 1.90, 95% CI, 1.11-3.27; P = 0.020) were associated with a high risk of progression in univariate analysis. In univariate analysis, high hemoglobin (Hb) levels (<median vs. >= median; HR, 0.41, 95% CI, 0.24-0.73; P = 0.0023) and high red cell distribution widths (<median vs. >= median; HR, 2.41, 95% CI, 1.37-4.25; P = 0.0023) were associated with a low and a high risk of all-cause mortality, respectively. In multivariate analysis, high Hb levels (< median vs. >= median; HR, 0.42, 95% CI, 0.22- 0.79; P = 0.0076) were repeatedly associated with a low risk of all-cause mortality. Conclusion: We found that white blood cell counts and neutrophil-to-lymphocyte ratios may be prognostic for progression-free survival while red cell distribution widths may be prognostic for OS. In particular, a low Hb level was a robust prognostic factor for poor OS. These findings could be useful in predicting prognosis in CRPC patients treated with ARPIs. (C) 2020 Elsevier Inc. All rights reserved.