[Screening test for prostate cancer].

Prostate specific antigen (PSA), digital rectal examination (DRE) and transrectal ultrasonography (TRUS) are widely used for the detection of prostate cancer. The sensitivity and positive predictive value of PSA are most excellent among these modalities. However, the sensitivity of PSA was 73% when the cut off value was 6ng/ml. In the general clinical practice the use of three screening modalities must be recommended to improve the detection rate. However, the mass screening which has to diagnose many subjects during a short period should be mainly conducted by PSA, because blood sampling for PSA was performed with other kind of mass screening without any specialists (urologists). We are now investigating the effects of age specific PSA and PSA velocity to improve the sensitivity of PSA. It is estimated that the prostate cancer death and the prevalence will rapidly increase in Japan. Therefore, we had better start the preventative research including mass screening. To prove the significance of mass screening program, pilot studies in well executed randomized prospective protocols are urgently needed.