KLK3 and pachyonychia congenita: To mitigate this, the IMPACT Study (Identification of Men with a genetic predisposition to PC: Targeted screening in BRCA 1/2 mutation carriers and controls) screened and enrolled 1522 PC patients with germline BRCA 1/2 mutation along with 959 controls [19] with annual prostate specific antigen (PSA) testing and warranting prostate biopsy if PSA >3ng/mL were performed.