Risk Stratification of Castration-resistant Prostate Cancer Patients Treated with Cabazitaxel

Patient characteristics before administering the first cycle of cabazitaxel for metastatic castration-resistant prostate cancer (mCRPC) were collected to assess prognostic factors for overall survival (OS). Multivariate analysis revealed that prostate-specific antigen (PSA) ≥100 ng/ml prior to cabazitaxel treatment, visceral metastasis, and low absolute monocyte count were independent prognostic indicators for OS. The aim of the present study was to investigate prognostic biomarkers in patients treated with cabazitaxel among Japanese metastatic castration-resistant prostate cancer (mCRPC) patients. In this retrospective study, 45 patients with mCRPC treated with cabazitaxel were reviewed retrospectively. Clinicopathological factors and laboratory data before administering the first cycle of cabazitaxel were collected to assess the prognostic factors for overall survival (OS). Treatment was generally well tolerated, with a median of 5 cycles (range, 1-26). Median OS from the start of cabazitaxel treatment was 16.1 months (95% confidence interval 6.8-25.5). Univariate analysis revealed that poor performance status, visceral metastasis, hemoglobin <11 mg/dl, absolute monocyte count <400/µl, and prostate-specific antigen ≥100 ng/ml prior to cabazitaxel treatment (P=0.002) were significantly associated with shorter OS. Multivariate analysis revealed that PSA ≥100 ng/ml prior to cabazitaxel treatment, visceral metastasis, and absolute monocyte count <400/µl were independent prognostic indicators for OS. Based on the relative risk of death, patients with mCRPC before cabazitaxel therapy were divided into three risk groups: Low, intermediate, and high (P<0.001). In conclusion, the practical implications of our results may assist in tailoring the introduction of cabazitaxel.