KLK3 and prostate carcinoma: Most previous population-based PCa screening trials with PSA, including the Cluster Randomized Trial of PSA Testing for Prostate Cancer (CAP), the PLCO trial, the PROBASE trial, the ERSPC, and the GÖTEBORG-2 Trial (Andriole et al., 2009; Arsov et al., 2013; Martin et al., 2018; Hugosson et al., 2019; Hugosson et al., 2022), used a single PSA cut-off value (≥3.0 or 4 ng/mL) as the definition of a positive PSA test and recommended further examinations after positive PSA.