Atypical onset of bicalutamide-induced liver injury

Anti-androgen therapy is the leading treatment for advanced prostate cancer and is commonly used for neoadjuvant or adjuvant treatment. Bicalutamide is a non-steroidal anti-androgen, used during the initiation of androgen deprivation therapy along with a luteinizing hormone-releasing hormone agonist to reduce the symptoms of tumor-related flares in patients with advanced prostate cancer. As side effects, bicalutamide can cause fatigue, gynecomastia, and decreased libido through competitive androgen receptor blockade. Additionally, although not as common, drug-induced liver injury has also been reported. Herein, we report a case of hepatotoxicity secondary to bicalutamide use. Typically, bicalutamide-induced hepatotoxicity develops after a few days; however, in this case, hepatic injury occurred 5 mo after treatment initiation. Based on this rare case of delayed liver injury, we recommend careful monitoring of liver function throughout bicalutamide treatment for prostate cancer.