PURPOSE: The current EAU-EANM-ESTRO-ESUR-ISUP-SIOG Guidelines recommend radiolabeled prostate-specific membrane antigen (PSMA), choline, or fluciclovine PET/CT at biochemical recurrence (BCR) of prostate cancer (PCa) after radical prostatectomy. Here, FOLH1 is linked to prostate carcinoma.