Clinical utility of proPSA and "benign" PSA when percent free PSA is less than 15%.

Objectives: To investigate the clinical utility of the subforms of free prostate-specific antigen (PSA), namely proPSA and "benign" PSA (BPSA), to improve cancer detection when the percent free PSA level is less than 15%. Percent free PSA, while maintaining sensitivity, has greatly improved the specificity of PSA for the early detection of prostate cancer. A low percent free PSA value indicates a greater risk of cancer, but only 30% to 50% of men with percent free PSA levels of less than 15% actually have cancer at biopsy.

Serum BPSA outperforms both total PSA and free PSA as a predictor of prostatic enlargement in men without prostate cancer.

Objectives: To determine whether the serum concentration of BPSA, a distinct form of free prostate-specific antigen (PSA) enriched in the nodular transition zone (TZ) tissue of benign prostatic hyperplasia (BPH), can predict TZ volume and diagnose BPH-associated prostatic enlargement in patients without prostate cancer.

Methods: We studied 91 consecutive patients without prostate cancer who underwent a 10-core or greater biopsy of the prostate. The associations between prostate volume, age, International Prostate Symptom Score, and serum concentrations of PSA, free PSA, and BPSA were evaluated by receiver operating characteristic curve and linear and binary logistic regression analyses.

Serum pro-prostate specific antigen preferentially detects aggressive prostate cancers in men with 2 to 4 ng/ml prostate specific antigen.

Purpose: Pro forms of prostate specific antigen (PSA) have been reported to be more cancer specific markers of prostate cancer than total PSA and they also may preferentially detect the more aggressive forms of the disease.

Materials And Methods: Research immunoassays with high specificity for pro-PSA forms were used to study 1091 retrospective serum specimens, including 555 with 2 to 4 and 536 with 4 to 10 ng/ml PSA, from men enrolled in prostate cancer screening studies who underwent prostate biopsy.

Results: In the 2 to 4 ng/ml PSA range the ratio of pro- to free-PSA (percent pro-PSA) using a cutoff of 1.

Proenzyme forms of prostate-specific antigen in serum improve the detection of prostate cancer.

Introduction: Pro or precursor forms of prostate-specific antigen (PSA) have emerged as potentially important diagnostic serum markers for prostate cancer detection. Immunoassays were developed to measure specific proPSA forms containing propeptides of 2, 4, and 7 amino acids [(-2)proPSA, (-4)proPSA, and (-7)proPSA, respectively].

Methods: Research-use dual monoclonal antibody immunoassays using europium-labeled detection monoclonal antibodies were developed for each form of proPSA.

Serum pro prostate specific antigen improves cancer detection compared to free and complexed prostate specific antigen in men with prostate specific antigen 2 to 4 ng/ml.

Purpose: Pro prostate specific antigen (pPSA) is a precursor form of PSA enriched in tumor compared to benign prostate tissues that may be a more specific serum marker for prostate cancer. Serum pPSA was measured in the clinically relevant early detection PSA range of 2 to 10 ng/ml.

Materials And Methods: Research use immunoassays were used to measure native and truncated forms of pPSA.

Proenzyme psa for the early detection of prostate cancer in the 2.5-4.0 ng/ml total psa range: preliminary analysis.

Objectives: To determine the clinical utility of using proenzyme prostate-specific antigen (pPSA) for early detection of prostate cancer in the 2.5 to 4.0 ng/mL total PSA range.

Benign prostate-specific antigen (BPSA) in serum is increased in benign prostate disease.

Background: BPSA is a "benign" form of free prostate-specific antigen (PSA) that is increased in prostate transition zone tissues of men with pathologic benign prostatic hyperplasia (BPH). We developed an immunoassay to determine the concentration of BPSA in the serum of men with BPH.

Methods: The BPSA antigen was purified by HPLC, and murine monoclonal antibodies were prepared by standard methods.