[Prostatic specific antigen in practice in 1997].

PSA (Prostate Specific Antigen) has modified the management of prostatic disease. Changes of PSA levels can be observed in many clinical circumstances other than cancer (endoscopic procedures, prostatitis, medications, etc.). Various methods have been proposed to increase the specificity of PSA in prostatic cancer, particularly when the PSA level is between 4 and 10 ng/ml: age-related PSA, PSA density, PSA velocity, freePSA. These methods allow more refined indications for transrectal biopsies of the prostate which provide the histological evidence essential for the diagnosis of cancer.