Effects of statin use on the response duration to androgen deprivation therapy in metastatic prostate cancer

PURPOSE: To determine whether statin use delays the development of castration-resistant prostate cancer (CRPC) in patients with metastatic prostate cancer treated with androgen deprivation therapy (ADT). MATERIALS AND METHODS: A total of 171 patients with metastatic prostate cancer at the time of diagnosis who were treated with ADT between January 1997 and December 2013 were retrospectively analyzed. The patients were classified into two groups: the nonstatin use group (A group) and the statin use group (B group). Multivariate analysis was performed on statin use and other factors considered likely to have an effect on the time to progression to CRPC. RESULTS: The mean patient age was 67.1±9.1 years, and the mean follow-up period was 52 months. The mean initial prostate-specific antigen (PSA) level was 537 ng/mL. Of the 171 patients, 125 (73%) were in group A and 46 (27%) were in group B. The time to progression to CRPC was 22.7 months in group A and 30.5 months in group B, and this difference was significant (p=0.032). Blood cholesterol and initial PSA levels did not differ significantly according to the time to progression to CRPC (p=0.288, p=0.198). Multivariate analysis using the Cox regression method showed that not having diabetes (p=0.037) and using a statin (p=0.045) significantly increased the odds ratio of a longer progression to CRPC. CONCLUSIONS: Statin use in metastatic prostate cancer patients appears to delay the progression to CRPC. Large-scale, long-term follow-up studies are needed to validate this finding.