KLK3 and Familial prostate cancer: The inverse association for diabetes remained in the subgroup of men with regular PSA testing, which were consistent with our previous results2 and findings from the Prostate, Lung, Colorectal, and Ovarian (PLCO) Screening Trial cohort.7 Moreover, when stratified on men with normal PSA levels at testing, the reduced risk of overall and nonaggressive prostate cancer among males with diabetes persisted.