[Prostatic specific antigen and prostatic pathology. Value of preoperative blood assay. Preliminary study apropos of 709 case reports].

Prostate specific antigen (PSA) is a prostate tissue marker detected by immunostaining in 97% of specimens examined. Tissue staining is variable and cancers are more heterogeneous than normal or hyperplastic prostate. Serum PSA levels in patients with normal or hyperplastic lesions are 12 ng/ml + 19 and are positively correlated with the weight of the gland. In patients with carcinoma serum PSA levels are 216 ng/ml + 782 and are positively correlated with tumor spread. PSA assay is of little value for screening for prostatic carcinoma. However, carcinoma of prostate is more frequent when PSA levels are above 10 ng/ml and the level of 50 ng/ml indicates capsular penetration, seminal vesicle or lymph node involvement or metastatic spread.