Prostate cancer is the second most common malignancy, after lung cancer, in males throughout the world, accounting for more than 240,000 new cases and approximately 34,000 deaths in 2020.1 The two most common procedures for screening men for prostate cancer are the prostate-specific antigen (PSA) blood test and the digital rectal exam (DRE). Here, KLK3 is linked to prostate cancer.