Multicenter evaluation of [-2]proprostate-specific antigen and the prostate health index for detecting prostate cancer.
Clin Chem
; 59(1): 306-14, 2013 Jan.
Article
em En
| MEDLINE
| ID: mdl-23213080
ABSTRACT
BACKGROUND:
Total prostate-specific antigen (tPSA) is flawed for prostate cancer (PCa) detection. [-2]proprostate-specific antigen (p2PSA), a molecular isoform of free PSA (fPSA), shows higher specificity compared with tPSA or percentage of free PSA (%fPSA). The prostate health index (Phi), a measure based on p2PSA and calculated as p2PSA/fPSA × âtPSA, was evaluated in a multicenter study for detecting PCa.METHODS:
A total of 1362 patients from 4 different study sites who had tPSA values of 1.6-8.0 µg/L (668 patients with PCa, 694 without PCa) underwent ≥10 core biopsies. Serum concentrations of tPSA, fPSA (both calibrated against a WHO reference material), and p2PSA were measured on Access2 or DxI800 analyzers (Beckman Coulter).RESULTS:
The percentage ratio of p2PSA to fPSA (%p2PSA) and Phi were significantly higher in all PCa subcohorts (positive initial or repeat biopsy result or negative digital rectal examination) (P < 0.0001) compared with patients without PCa. Phi had the largest area under the ROC curve (AUC) (AUC = 0.74) and provided significantly better clinical performance for predicting PCa compared with %p2PSA (AUC = 0.72, P = 0.018), p2PSA (AUC = 0.63, P < 0.0001), %fPSA (AUC = 0.61) or tPSA (AUC = 0.56). Significantly higher median values of Phi were observed for patients with a Gleason score ≥7 (Phi = 60) compared with a Gleason score <7 (Phi = 53; P = 0.0018). The proportion of aggressive PCa (Gleason score ≥7) increased with the Phi score.CONCLUSIONS:
The results of this multicenter study show that Phi, compared with tPSA or %fPSA, demonstrated superior clinical performance in detecting PCa at tPSA 1.6-8.0 µg/L (i.e., approximately 2-10 µg/L in traditional calibration) and is better able to detect aggressive PCa.
Texto completo:
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Base de dados:
MEDLINE
Assunto principal:
Neoplasias da Próstata
/
Antígeno Prostático Específico
Tipo de estudo:
Clinical_trials
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Diagnostic_studies
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Observational_studies
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Prognostic_studies
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Risk_factors_studies
Limite:
Humans
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Male
Idioma:
En
Ano de publicação:
2013
Tipo de documento:
Article