This pilot study aimed to evaluate the impact of short-term dutasteride treatment on standardized uptake values (SUVmax) in PSMA PET imaging and the immunohistochemical expression of PSMA for the first time in humans.<h4>Methods</h4>Four prostate cancer (PCa) patients underwent an initial PSMA PET/MRI of the prostate. The gene discussed is FOLH1; the disease is Familial prostate cancer.