A recent report from the European Randomized Study of Screening for Prostate Cancer (ERSPC) and Prostate, Lung, Colorectal and Ovarian Cancer Screening Trial (PLCO) indicates a continued need for novel biomarkers to supplement serum PSA to accurately predict PCa risk and stratification of indolent and aggressive PCa [22, 23]. This evidence concerns the gene KLK3 and prostate cancer.