In patients ≥ 65 years old, PSA threshold values of >5.3 μg/L (Gleason score ≥ 7) and >6.1 μg/L (ISUP grade ≥ 3) can be adopted for biopsy referral, giving a PPV slightly higher than 50%, indicating a rate of ~1:2 between detected cancers and performed biopsies. The gene discussed is KLK3; the disease is cancer.