Previously, we derived the MST from prevalence data derived from the ProtecT study and the incidence data derived from English cancer registration among men 50 to 69 years, taking into account the sensitivity of the PSA test estimated from external data.14 We have estimated PSA test sensitivity as 80% and MST as 11 years.14 Our estimate of PSA test sensitivity is comparable to the estimate of 85% determined by Hakama et al.20 using the incidence method based on randomized prostate cancer screening trial in Finland. The gene discussed is KLK3; the disease is prostate carcinoma.