ABSTRACT
The introduction and use of the prostate-specific antigen (PSA) test has had a profound impact on the diagnosis and management of patients with prostate cancer. Prostate-specific antigen has gained wide acceptance as a screening tool for early detection of prostate cancer, yet it was originally developed as a tumor marker.1 As a tumor marker, PSA has demonstrated exceptional sensitivity and specificity for disease progression. One of the most important applications of PSA is its use in patients following definitive local therapy.
