Prostate-Specific Antigen Flare Phenomenon Induced by Abiraterone Acetate in Chemotherapy-Naive Patients With Metastatic Castration-Resistant Prostate Cancer

The PSA flare phenomenon is not rare event during AA treatment. A PSA decline during AA treatment, with or without a PSA flare, was associated with favorable clinical outcomes. Thus, AA should not be withdrawn early in patients with mCRPC in whom an initial, isolated PSA increase has been observed.