The development of potent novel androgen receptor inhibitors (ARi) such as apalutamide have improved the life expectancy in men with castration-resistant prostate cancer (CRPCa). However, some serious toxicity can occur limiting the choice of treatment in CRPCa. In our case, the patient experienced severe toxicity after initiation of apalutamide. Diagnostic PSMA-PET/CT confirmed the recurrence and tailored the treatment with ^(177)Lu-PSMA-617 (RLT), a beta emitter radionuclide. RLT resulted …