Prostate specific antigen (PSA) was measured in benign and malignant gland using the immunoradiometric assay (IRMA) .In sera of 36 patients with prostate cancer the mean value of PSA was 50 ng /ml while the obtained mean value from 52 patients with BPH was 7.1 .The characteristics of the binding of tissues PSA of Prostate cancer with labelled iodine 125 -anti total PSA antibody were investigated . Different factors affecting this binding were extensively...