Accuracy of the Prostate Health Index versus the urinary Prostate Cancer Antigen 3 score to predict overall and significant prostate cancer at initial biopsy - Abstract

BACKGROUND: It remains unclear whether the Prostate Health Index (PHI) or the urinary Prostate-Cancer Antigen 3 (PCA-3) score is more accurate at screening for prostate cancer (PCa).

The aim of this study was to prospectively compare the accuracy of PHI and PCA-3 scores to predict overall and significant PCa in men undergoing an initial prostate biopsy.

METHODS: Double-blind assessments of PHI and PCA-3 were conducted by referent physicians in 138 patients who subsequently underwent trans-rectal ultrasound-guided prostate biopsy according to a 12-core scheme. Predictive accuracies of PHI and PCA-3 were assessed using AUC and compared according to the DeLong method. Diagnostic performances with usual cut-off values for positivity (i.e., PHI >40 and PCA-3 >35) were calculated, and odds ratios associated with predicting PCa overall and significant PCa as defined by pathological updated Epstein criteria (i.e., Gleason score ≥7, more than three positive cores, or >50% cancer involvement in any core) were estimated using logistic regression.

RESULTS: Prevalences of overall and significant PCa were 44.9% and 28.3%, respectively. PCA-3 (AUC = 0.71) was the most accurate predictor of PCa overall, and significantly outperformed PHI (AUC = 0.65; P = 0.03). However, PHI (AUC = 0.80) remained the most accurate predictor when screening exclusively for significant PCa and significantly outperformed PCA-3 (AUC = 0.55; P = 0.03). Furthermore, PCA-3 >35 had the best accuracy, and positive or negative predictive values when screening for PCa overall whereas these diagnostic performances were greater for PHI >40 when exclusively screening for significant PCa. PHI > 40 combined with PCA-3 > 35 was more specific in both cases. In multivariate analyses, PCA-3 >35 (OR = 5.68; 95%CI = (2.21-14.59); P < 0.001) was significantly correlated with the presence of PCa overall, but PHI >40 (OR = 9.60; 95%CI = (1.72-91.32); P = 0.001) was the only independent predictor for detecting significant PCa.

CONCLUSIONS: Although PCA-3 score is the best predictor for PCa overall at initial biopsy, our findings strongly indicate that PHI should be used for population-based screening to avoid over-diagnosis of indolent tumors that are unlikely to cause death.

Written by:
Seisen T, Rouprêt M, Brault D, Léon P, Cancel-Tassin G, Compérat E, Renard-Penna R, Mozer P, Guechot J, Cussenot O.   Are you the author?
Academic Department of Urology, Pitié-Salpétrière Hospital, AP-HP, Paris, France; UPMC Univ Paris 06, GRC5, ONCOTYPE-URO, Institut Universitaire de Cancérologie, Paris, France.

Reference: Prostate. 2014 Oct 18. Epub ahead of print.
doi: 10.1002/pros.22898

PubMed Abstract
PMID: 25327361 Prostate Cancer Section