Prostate-specific antigen: a valuable clinical tool

Abstract

Because approximately 30% of patients with benign prostatic hyperplasia (BPH) only will have an elevated serum PSA concentration, it is unlikely that PSA by itself will become an effective screening tool for the early diagnosis of prostate cancer. However, if combined with digital rectal examination (DRE) and/or transrectal ultrasound, it may become a vital part of any early detection program. Although there is a direct correlation between the serum PSA concentration and clinical stage, PSA is not sufficiently reliable to determine the clinical stage on an individual basis. This finding also applies to pathologic stage. Low preoperative serum PSA concentrations in patients with previously untreated prostate cancers, however, are predictive of a negative radionuclide bone scan. With respect to monitoring patients after definitive therapy, PSA is an exquisitely sensitive tumor marker. Irrespective of the treatment modality, PSA reflects accurately the tumor status of the patient and is prognostic of eventual outcome.