Efficacy and safety of docetaxel and prednisolone for castration-resistant prostate cancer: a multi-institutional retrospective study in Japan.

OBJECTIVE Although some new drugs for castration-resistant prostate cancer are available, docetaxel still plays an important role in castration-resistant prostate cancer treatment. In this study, we evaluated the efficacy and safety of docetaxel and prednisolone in patients with castration-resistant prostate cancer. METHODS We conducted a retrospective chart review of castration-resistant prostate cancer patients who received docetaxel and prednisolone at 14 hospitals in the Sapporo Medical University Urologic Oncology Consortium from August 2004 to December 2011. RESULTS A total of 140 patients with castration-resistant prostate cancer received docetaxel and prednisolone (median age, 73.8 years; median prostate specific antigen, 54.7 ng/ml). A median of six cycles (range: 1-43) of docetaxel and prednisolone was administered per patient. Median follow-up was 13.7 months. Median overall survival was 22.0 months. The log-rank test revealed that prostate specific antigen before docetaxel and prednisolone (<50 ng/ml) and the prostate specific antigen reduction rate (≥30%) were associated with overall survival (P < 0.001 and P < 0.001, respectively). Eighty patients (57.1%) achieved a prostate specific antigen reduction rate of over 30%. All except two (97.5%) reached 30% prostate specific antigen reduction within five cycles of docetaxel and prednisolone. There were two (1.4%) treatment-related deaths due to adverse events, which were interstitial lung disease, and febrile neutropenia and bacterial pneumonia. Interstitial lung disease occurred in 14 (10.0%) patients within a median of 2.5 cycles of docetaxel and prednisolone. Grade 5 interstitial lung disease was seen after three cycles of docetaxel and prednisolone. CONCLUSIONS If a prostate specific antigen reduction rate of over 30% is not obtained within five cycles of docetaxel and prednisolone, other treatment options should be considered. Although most patients safely received docetaxel and prednisolone, we must always keep interstitial lung disease in mind as a possible lethal adverse event.