Prostate Specific Antigen is Metabolized in the Liver

AbstractPurpose: The site of metabolism of prostate specific antigen (PSA) was determined.Materials and Methods: In a prospective study, during clinically indicated left and right heart catheterizations for various cardiac diseases in 12 men (mean age 62.5 plus/minus 8.3 years, standard deviation), selective blood samples were obtained from the infra-renal, infra-hepatic and supra-hepatic inferior vena cava, renal vein, superior vena cava, pulmonary artery and femoral artery. Mean PSA concentration was calculated for all vascular sites. Using a paired Student t test, the mean difference between the afferent and efferent PSA concentrations across the renal, hepatic, pulmonary and pelvic circulation was calculated.Results: The hepatic gradient between the infra-hepatic and suprahepatic inferior vena cava showed the greatest decrease (0.11 plus/minus 0.16 ng./ml. or 8.3 percent) in PSA concentration and was statistically significant (p = 0.04). A smaller decrease across the pulmonary circulation was statisti...