Influence of high-grade prostatic intra-epithelial neoplasia on total and percentage free serum prostatic specific antigen.

Abstract

To analyse the influence of high-grade prostatic intra-epithelial neoplasia (HGPIN) on total and percentage free serum prostatic specific antigen (PSA). The total and free serum PSA levels were measured (using a double-monoclonal antibody immunoassay, Tandem and Tandem free PSA, Hybritech Inc, Liège, Belgium) in 570 consecutive patients undergoing sextant ultrasound-guided prostatic biopsy because of an abnormal digital rectal examination or a serum PSA concentration of > 4.0 ng/mL. The main diagnosis was benign disease in 321 (56%) and prostate cancer in 249 (44%). HGPIN was detected in 85 (15%) of the patients; in 17 (20%) it was associated with benign tissue and in 68 (80%) with prostate cancer. Patients with benign disease had a median total serum PSA level of 7.2 with no HGPIN and 7.7 ng/mL when HGPIN was present (P>0.05); the corresponding values in patients with prostate cancer were 16.0 and 15.9 ng/mL (P>0.05). The median percentage free serum PSA was 15.8 in patients with HGPIN-free benign disease and 14.1 when HGPIN was present (P>0.05); the corresponding values in patients with prostate cancer were 9.7 and 11.0 (P>0.05). In a multivariate analysis, prostate cancer was the major contributor to total and percentage free serum PSA levels. The presence of HGPIN does not contribute significantly to total and percentage free serum PSA levels.