KLK3 and pachyonychia congenita: According to the Unied States of America’s National Cancer Institute, men with blood PSA levels of >4 ng/ml are recommended to undergo prostate biopsy for examination of prostatic tissue for the presence of abnormal tumor cells.12 In the Saudi population included in this study, we found that 92% of the patients with PC had recorded PSA levels of >4 ng/ml.