LAUSR

e598Background: In this study, we evaluated our cohort treated with enzalutamide retrospectively. We focused on Gleason pattern 5 prostate cancer which was very aggressive cancer and we investigated the difference in efficacy of enzalutamide between the groups including Gleason pattern 5 or not, to understand if initial aggressiveness of prostate cancer influence the enzalutamide responses. Methods: A total of 190 CRPC cases treated with enzalutamide between June 2014 and July 2016 at our university and affiliated institutions were included in this study. We evaluated clinical and pathological factors, Prostate specific antigen(PSA) responses, and overall survival, retrospectively. Results: Of these, 80 cases did not have Gleason pattern 5 and 110 cases had Gleason pattern 5 (Gleason Score 4+5, 5+4 or 5+5). Initial PSA level was higher and metastasis was more frequent in Gleason pattern 5 group (p = 0.0328, and 0.0171, respectively). Docetaxel pretreatment, abiraterone pretreatment, PSA and other serologi...