Our Experience with Abiraterone and Enzalutamide in the Treatment of Metastatic Castration-Resistant Prostate Cancer: Retrospective Real-Life Data

ABS TRACT Objective: In recent years, agents targeting the androgen signaling pathway, such as abiraterone and enzalutamide, have be- come increasingly crucial in the treatment of metastatic castration-resistant prostate cancer (mCRPC). This study aimed to compare the effectiveness of both agents retrospectively. Material and Methods: Patients with the diagnosis of mCRPC who received abiraterone (ABI group) or enzalutamide (ENZA group) and who were followed up and treated in our clinics were analyzed retrospectively. Results: A total of 59 patients, 23 receiving abiraterone and 36 enzalutamide, were included in the study. Moreover, the prostate-specific antigen (PSA) level reduced by more than 50% in 33 (14 in the ABI group and 19 in the ENZA group) patients. The median progression-free survival (PFS) and overall survival-2 (OS-2) were 7.46±2.08 months and 13.60±6.19 months in the ABI group and 8.80±4.21 months and 21.03±3.84 months in the ENZA group (p=0.448; p=0.571), respectively. When the Cox regression analysis was performed, PSA reduction of more than 50% was statistically significant for OS-2 but not for PFS (p=0.023). Conclusion: Both abiraterone and enzalutamide are effective treatment agents for mCRPC. The decrease in the PSA value is a crucial predictive marker in evaluating the effectiveness of the treatment.