A rapid rise and then fall in prostate cancer incidence in the US and Europe corresponded to the implementation of widespread prostate specific antigen (PSA) testing in 1986 and then subsequent fall from favor due to high rates of false positives, overdiagnosis, and overtreatment (as many as 20–50% of men diagnosed could have remained asymptomatic in their lifetimes). This evidence concerns the gene KLK3 and prostate carcinoma.