Comparison of the oncological outcomes of abiraterone acetate and enzalutamide in metastatic castration-resistant prostate cancer: A multicenter real-life data

Background: To compare enzalutamide (E) and abiraterone acetate (AA) in terms of efficacy, survival and prognostic factors affecting survival in metastatic castration-resistant prostate cancer (mCRPC) patients. Methods: : A total of 250 patients treated with E or AA in 5 centers were included. Results: : The number of patients with no prostate specific antigen (PSA) decline was higher in the AA group than that in the E group, and the proportion of patients with a PSA decline of ≥50% was higher in the E group (p = 0.020). The rate of progression in the AA group (82.2%) was significantly higher than that in the E group (p <0.001). Radiological progression free survival (rPFS) and overall survival (OS) were significantly longer in the E group when compared to that in the AA group (p <0.001 and p = 0.027, respectively). In the E group, rPFS was significantly longer than that in the AA group in both pre- and post-docetaxel settings (p=0.010 and p=0.003, respectively). OS was similar in the pre-docetaxel setting; but in the post-docetaxel setting, E group had a significantly longer OS than the AA group(p=0.021). In the multivariate analysis performed in the whole patient group, we found that good prognostic factors for rPFS were E treatment, being ≥75 years and a PSA decline of ≥50% while there was no factor affecting OS. Conclusion: With longer OS and PFS, E seems to be more suitable for mCRPC patients in the post-docetaxel setting than AA.