Appropriate definition of non-metastatic castration-resistant prostate cancer (nmCRPC) and optimal timing of androgen receptor signaling inhibitor (ARSI).

The timely initiation of ARSI is paramount in nmCRPC management. Our findings strongly advocate for consideration of ARSI administration in nmCRPC patients before their PSA levels exceed 2.0 ng/mL. Our results indicated a PSA threshold of 1.0 ng/mL for nmCRPC definition which is more reasonable to administer ARSI without delay.