Évolution des formes moléculaires de l'antigène spécifique de la prostate chez des groupes sérologiques de patients atteints de pathologies prostatiques

The prostate-specific antigen (PSA) is a human tissular kallikrein used as serum tumoral marker of prostate cancer. The Total PSA and its molecular forms were detected at several different proportions in both patients with benign prostatic hyperplasia (BHP) and patients with prostate cancer (PCa). The purpose of the present study was to measure the total PSA in patients with these pathologies and to analyse the free PSA's evolution in each pathology group. Serums were taken from 90 patients with BHP and 23 with PCa. The DPC Immulite assays was used to determine total PSA and free PSA levels. The cut-off total PSA was 4 ng/ml. On a second hand were revelled that total PSA levels were variable in both BPH and PCa patients considering cut-off value. We showed that for BPH patients, 47 out of 90 present total PSA levels between 4-20 ng/ml, 6/90 between 20-100 ng/ml and 2/90 between 10-500 ng/ml. For PCa patients, 6 out of 23 present total PSA levels lower than 4 ng/ml. While, 2/23 of them between 4-20 ng/ml, 11/23 between 20-100 ng/ml and 4/23 between 100-900 ng/ml. Each serological group present a characteristic distribution of free molecular form of PSA, free PSA, marked by progressive free PSA level in related with total PSA. This individual concentration is variable in groups of patients having PSA levels higher than 20 ng/ml. The analysis of percentage free PSA/total PSA in each group of patient's showed characteristic percentages with a significant difference between BHP and PCa patients essentially in group with total PSA level between 4-20 ng/ml (P = 0,0004), followed a less significant difference less for the group with total PSA between 0-4 ng/ml. Differences are not significant in groups patient's with total PSA higher than 20 ng/ml.