In man, the prostate antigen (PSA) is secreted by the prostate. The prostate antigen level gives information about the prostate physiological condition. Thus, levels above the norm may show pathology of the prostate (benign hypertrophy, prostatitis, cancer, etc.).

The PSA assay should be performed at least once a year in men over 50 years. In case of prostate proble, early sceening allows considerably increasing recovery possibilities.