KLK3 and prostate cancer: The European Randomised Study of Screening for Prostate Cancer (ERSPC) and the GÖTEBORG-1 (G1) trials demonstrated a 20%–30% reduction in prostate cancer-specific mortality at 16–22 years of follow-up.1, 3 The main harms of screening are overdiagnosis and overtreatment with side-effects that may significantly impact men’s quality of life.24, 6 Given the uncertain balance between benefits and harms, most organisations and guidelines recommend that asymptomatic men participate in shared decision making about PSA-testing.7 8