Personalizing Enzalutamide Therapy by Understanding the Relation Between Tumor mRNAs, miRNAs and Treatment Response

Inclusion Criteria: * Male patients with chemotherapy naive metastatic castration resistant prostate cancer\* * Age at least 18 years * Patients from who it is possible to collect blood samples * Patient who are able and willing to give written informed consent prior to screening and enrollment * Life expectancy of \> 6 months * Measurable disease \*definition of CRPC according to EAU guidelines 2014 Exclusion Criteria: * None The study objective is to explore the effect of enzalutamide on biomarker exposure in a group of patients treated with enzalutamide in agreement with the drug label. Therefore no strict exclusion criteria will be used in this study