Enzalutamide in patients with castration-resistant prostate cancer: retrospective, multicenter, real life study.

BACKGROUND Metastatic castration-resistant prostate cancer (mCRPC) is the final stage of pCa history and represents a clinically relevant phenotype with an elevated burden of mortality. The aim of the present study is to evaluate the efficacy and safety of enzalutamide in a "real-life" setting in mCRPC patients. METHODS Data about all mCRPC patients treated with enzalutamide from September 2017 to September 2018 were collected. Demographics, comorbidities, clinical parameters, outcomes, toxicity, overall survival and progression free survival were analyzed. RESULTS Overall 158 patients were enrolled. Mean age was 75.8 (±8.7) years with a baseline median PSA of 16.5 (IQR 7.4-47.8) ng/mL. The median follow-up lasted 7.7 (IQR 4-14.1) months. Of all the 10.1% of patients reported grade 3-4 adverse events. 43.7% of patients experienced a progression. Overall the 6 and 12 months PFS rates were 69.5% (95% CI: 61.7-78.3%) and the 45.6% (95% CI: 36.5-57.1%); a median baseline PSA >16 ng/mL (HR:2.0, 95% CI: 1.2-3.3, p=0.005), the use of opioid (HR:3.1, 95% CI 1.9-5.0, p<0.001), a previous treatment (abiraterone, docetaxel or abiraterone + docetaxel) were significantly associated with higher rates of cancer progression. Conversely, a brief pain questionnaire of 0-1 (HR: 0.4, 95% CI: 0.2-0.7, p<0.001), a 12 weeks 50% PSA reduction (HR: 0.4, 95% CI: 0.2-0.8, p=0.006) and a longer time to mCRPC (HR: 0.4, 95% CI: 0.3-0.7, p=0.002) were related to lower cancer progression rates. CONCLUSIONS Our data shows an effective and safe profile of enzalutamide in a "realworld" perspective in patients with mcRPC.