Rationale: Understanding the mechanisms of enzalutamide as an androgen receptor inhibitor in early prostate cancer could lead to improved patient selection for treatment.~Objective: To study the effects of enzalutamide on surgical margin status and AR / DNA interaction and gene expression.~Study design: A phase II prospective single-arm analysis. With a power of 80% to detect an expected reduction in positive surgical margin rate from 34% to 17% the investigators will have to included 55 men. For the AR/DNA interaction patients will serve as there own control since biopsies will be taken before and after enzalutamide treatment.~Study population: Patients over 18 years of age with localized prostate cancer that are planned for prostatectomy.~Intervention : Men with localized prostate cancer will undergo an additional set of targeted tumor biopsies and will be subsequently treated with 3 months of enzalutamide. The prostatectomy specimen will be additionally sampled, ex vivo.~Main study parameters/endpoints: 1. The effects of neoadjuvant androgen ablation on tumor downstaging. 2. The genetic and transcriptional changes caused by neoadjuvant androgen ablation by enzalutamide.~Nature and extent of the burden and risks associated with participation, benefit and group relatedness: Burden and risks: Patients will be submitted to an additional set of 4 tumor targeted biopsies under local anesthesia and antibiotic prophylaxis. This comprises a 5 minute intervention with an elevated (2%) risk of postbiopsy urinary tract infection. Additionally oral enzalutamide treatment for a period of 3 months will result in temporary signs of androgen ablation such as: hot flushes (20%), headache (12%), diarrhea (1%), and seizures (0.9%). Benefits: neoadjuvant enzalutamide treatment has been shown to result in tumor and prostate downsizing. Earlier neoadjuvant androgen ablation studies with other agents have shown a reduced positive surgical margin rate and reduced intraoperative blood loss
Rationale: Understanding the mechanisms of enzalutamide as an androgen receptor inhibitor in early prostate cancer could lead to improved patient selection for treatment.~Objective: To study the effects of enzalutamide on surgical margin status and AR / DNA interaction and gene expression.~Intervention : Men with localized prostate cancer will undergo an additional set of targeted tumor biopsies and will be subsequently treated with 3 months of enzalutamide. The prostatectomy specimen will be additionally sampled, ex vivo.