KLK3 and prostate carcinoma: In the PRIMARY2 study (NCT05154162), which is a currently recruiting non-inferiority trial (powered on the PRIMARY1 study outcomes) of the prostate MRI plus PSMA-PET/CT to detect clinically significant prostate cancer, only PI-RADS 3 and PI-RADS 2 patients with high-risk features are allowed to participate (PSA density > 0.1 ng/ml2, abnormal digital rectal exam, strong family history, BRCA mutation, PSA > 10, PSA doubling time < 36 months, PSA velocity > 0.75 ng/ml/yr).