Low-dose docetaxel, estramustine and prednisolone combination chemotherapy for castration-resistant prostate cancer

The objective of this study was to report our experience with weekly low-dose docetaxel (DOC) chemotherapy for patients with castration-resistant prostate cancer (CRPC). From 2007 to 2014, 39 consecutive patients received weekly low-dose DOC; the oncological effectiveness, side effects and tolerability were prospectively analyzed. The median patient age, serum prostate-specific antigen (PSA) level and Gleason score at diagnosis of prostate cancer were 71 years (range, 55-83 years), 187 ng/ml (range, 2.0-1711 ng/ml) and 8 (range, 5-10), respectively. The median number of cycles of DOC was 7 (range, 1-45 cycles). Of the 39 patients, the PSA level decreased by >50% in 13 (33%). In the multivariate analysis of prediction of patient overall survival, a decrease of the PSA level to <50% was a significant predictor (hazard ratio = 6.913; 95% confidence interval: 1.147-41.669; P=0.035). The median cancer-specific overall survival from the diagnosis of CRPC was 16.7 months (range, 2-54 months). Grade 3 toxicities were observed in 5 patients (13%); specifically, limb edema, nausea and hepatic disorders were detected in 2 (5%), 2 (5%) and 1 patient (3%), respectively. Treatment-related death (grade 5) occurred in 1 patient due to interstitial pneumonia after two courses of chemotherapy. The chemotherapy was completed in the majority of the patients (n=37, 94.8%) in the outpatient department, without interruption. These findings suggest that weekly low-dose DOC is feasible and safe for selected patients with CRPC, without treament with novel agents, such as abiraterone, enzalutamide and cabazitaxel.