The survival outcome, prostate-specific antigen (PSA) response and risk of fatigue of enzalutamide as first- and later-line treatment options in patients with metastatic castration-resistant prostate cancer (mCRPC): The real-world experience.

330Background: The real-world data regarding the efficacy and toxicity, particularly fatigue, of Enzalutmide (Enza) as first and later line treatment options in mCRPC patients is currently lacking. We aimed to evaluate the survival outcome, PSA response and rate of fatigue of Enza in clinical practice outside trial setting. Methods: The clinical records of mCRPC patients treated with Enza from all 7 public oncology centers in Hong Kong between August 2015 and October 2017 were reviewed. The treatment efficacy and its determinants, and toxicities were determined. Results: A total of 117 mCRPC patients were treated with Enza, of whom 29.1%, 48.7%, 19.3% had Enza as their first (chemo-naive), 2nd (post-docetaxel or abiraterone) and 3rd or above (had at least 2 of the prior followings: docetaxel, abiraterone, cabazitaxel or radium-223) line treatment options. Visceral metastases were present in 20.6/29.8/50% patients with 1st/ 2nd / 3rd or above line Enza. The median overall survival (OS) and progression-free...