AR and Familial prostate cancer: Although new generation androgen receptor (AR) pathway inhibitors (ARPIs) are effective in prolonging the survival of patients with metastatic prostate cancer [1, 2], emerging evidence indicates that a subtype of castrate-resistant prostate cancer, called treatment-induced neuroendocrine prostate cancer (t-NEPC), is becoming more prevalent due to the selection pressure of ARPIs [3–6].