KLK3 and Familial prostate cancer: Data reported from the randomly selected, untreated controls in the Prostate Cancer Prevention Trial (PCPT) who underwent end-of-study prostate biopsy showed that PSA levels in blood were associated with evidence of prostate cancer at biopsy (AUC: 0.68) but that there was no PSA threshold in men aged 62–91 below which the presence of any prostate cancer lesion can be ruled out [30].