KLK3 and cancer: Very low- or low-risk localized PCa is defined to include tumor stage (T1c, prostate-specific antigen [PSA] detected or T2a, small palpable nodule); PSA value (less than 10 ng/mL); Gleason score (≤ 6); and extent of disease in biopsy (<3 biopsy cores positive and ≤50% cancer in any cores) [3] (reviewed in [4, 5]).