(UroToday.com) In the on-demand poster session of the European Society for Medical Oncology (ESMO) Annual Congress, Dr. Klara Kvorning Ternov presented an analysis of treatment-related changes in serum androgens for patients treated with abiraterone or enzalutamide in the context of a randomized controlled trial. There is a rationale for a potential difference. While enzalutamide and abiraterone acetate plus prednisone are both androgen receptor targeting treatments for metastatic castration-resistant prostate cancer (mCRPC), mechanistically they differ as abiraterone acetate inhibits the androgen production, whereas enzalutamide blocks the androgen receptor signaling.