Background/Objectives: The aim of this study was to investigate the relationship between the PRIMARY score derived from [68Ga]Ga-PSMA PET/CT and key clinical and pathological parameters of prostate cancer aggressiveness, including the PSA level, ISUP Grade Group, and D’Amico risk classification, in patients with biopsy-proven prostate cancer. The gene discussed is FOLH1; the disease is Familial prostate cancer.