KLK3 and prostate cancer: In common with D’Amico et al., the “German S3-Guideline for Prostate Cancer” and the European Association of Urology (EAU)-guideline (see Additional file 11) define HRLPCa as having prostate specific antigens (PSA) at a level of > 20 ng/ml, a Gleason score (GS) ≥8, or clinical stage ≥ T2c [8, 9].