In the past decade, serum prostate-specific antigen (PSA) concentration has become an essential tool in the diagnosis of early, curable prostate cancer. Its clinical utility has been enhanced further by the use of parameters such as the age-specific reference ranges that increase the sensitivity for detecting clinically significant prostate adenocarcinoma in young men<sup>23Oesterling J.E., Jacobsen S.J., Chute C.G., e al. Serum prostate-specific antigen in a community-based population of healthy men: Establishment of age-specific reference ranges JAMA 1993 ;  270 : 860

Cliccare qui per andare alla sezione Riferimenti</sup> and percent free PSA, which allows for better specificity for prostate cancer if the serum PSA level is mildly elevated.<sup>16Lilja H., Christensson A., Dahlen U., e al. Prostate-specific antigen in serum occurs predominantly in complex with alpha 1-antichymotrypsin Clin Chem 1991 ;  37 : 1618

Cliccare qui per andare alla sezione Riferimenti, 29Stenman U.H., Leinone J., Alfthan H., e al. A complex between prostate-specific antigen and alpha-1-antichymotrypsin is the major form of prostate-specific antigen in serum of patients with prostate cancer: Assay of the complex improves clinical sensitivity for cancer Cancer Res 1991 ;  51 : 222

Cliccare qui per andare alla sezione Riferimenti</sup> Despite these advances, PSA is not a cancer-specific serum marker, and various physiologic and benign pathologic processes have an effect on the serum PSA concentration. In this article, the effects of prostatitis, urinary retention, ejaculation, and ambulation on the serum PSA concentration are discussed.