Prostatic-specific antigen: clinical experience utilizing immunoperoxidase staining techniques in patients with metastatic prostate cancer.

A human prostatic-specific antigen was first purified in 1979 by M.C. Wang et al. In the years to follow, investigators have been able to develop antisera to prostatic-specific antigen. Using an immunoperoxidase technique to stain both fresh and archival specimens, tissue of prostatic origin can be identified. The stain in our experience has been both specific and sensitive as an indicator of extraprostatic spread of carcinoma. We describe five cases where this technique has been useful in clinical practice.