[Significance of the PSA-concentration for the detection of prostate cancer].

Prostate cancer among adult males is the most common neoplasm in western countries. Prostate specific antigen (PSA) is now a well established tumor marker that aids in the early detection of localized prostate cancer. Increased PSA concentrations are found in the serum of patients with benign prostatic hyperplasia or patients with prostate cancer, respectively. Therefore, in general the specificity of this test is low. The diagnostic value of PSA can be improved in consideration of clinical data, patients age, the measurement of free or complexed PSA, and the measurement of PSA velocity, respectively. Furthermore, there is a high variability between commercial PSA assays. Finally, the pre-analytical laboratory procedures have a high impact on the PSA measurement.