Objective: Even though the exact mechanism is largely unknown until now, statins are supposed to improve survival outcomes in various malignancies. For prostate cancer however, statins are known to compete with dehydroepiandrosterone (DHEAS) for the transport into the cytosol both using the cell by the Solute Carrier Transporter and thus diminish the cellular uptake of DHEAS as a precursor of androgens. Abiraterone inhibits CYP17A1 and thus effectively decreases the production of all relevant androgens including DHEAS. In this study we examined whether statins still affect survival outcome in patients with metastatic castration resistant prostate cancer (mCRPC) when treated with Abiraterone.
Patients and methods: 108 men with mCRPC treated with Abiraterone from 02/2010 to 07/2015 with (n = 21) or without (n = 87) concomitant treatment with statins were investigated. Progression free survival (PFS) and overall survival (OS) were analyzed using Kaplan-Meier-estimates and univariate Cox-regression analysis. The influence on best clinical benefit under Abiraterone treatment was analyzed with bivariate and multivariate logistic regression analysis.
Results: PSA-decline ≥ 50% was not significantly different in both groups (57 vs. 53%; p = 0.73). The median PFS (9 vs. 10 months; p = 0.97) and OS (14 vs. 18 months; p = 0.77) did not differ significantly between those men treated with and without concomitant statin therapy, respectively. Accordingly, there was no improvement for best clinical benefit in patients using statins (odds ratio: 1.2 (CI: 0.4-4.2); p = 0.76).
Conclusion: Use of statins as concomitant medication did not improve survival outcomes or best clinical benefit in men with mCRPC treated with Abiraterone.