Clinical utility of the PCA3 urine assay in European men scheduled for repeat biopsy

Haese A, de la Taille A, van Poppel H, Marberger M, Stenzl A, Mulders PFA, Huland H, Abbou C-C, Remzi M, Tinzl M, Feyerabend S, Stillebroer AB, van Gils MPMQ, Schalken JA. Eur Urol 2008;54:1081-8

• This European study in 463 men with 1-2 previous negative biopsies confirms the clinical utility of the Prostate CAncer gene 3 (PCA3) Score in guiding the decision which men need a repeat biopsy.
• The PCA3 Score may also be indicative of clinical stage and significance of prostate cancer (PCa).
• The PCA3 Score was superior to % free prostate specific antigen (PSA) for predicting repeat biopsy outcome.
• The probability of a positive repeat biopsy increased with higher PCA3 Scores.
• The mean PCA3 Score was statistically significantly higher in men with a positive repeat biopsy than in men with a negative repeat biopsy (Figure).
• The PCA3 Score was independent of the number of previous negative biopsies, age, prostate volume and serum total PSA level.
• The mean PCA3 Score was statistically significantly higher in men with clinical stage T2 vs. T1c and Gleason score >= 7 vs. < 7 (Figure).
• The mean PCA3 Score was statistically significantly higher in men with ‘significant’ PCa vs. ‘indolent’ PCa (Figure).
• The mean PCA3 Score was statistically significantly higher in men with high-grade prostate intraepithelial neoplasia (HGPIN) vs. those without HGPIN.

Figure: Mean and median PCA3 Score

Bx-: men with negative repeat biopsy; Bx+: men with a positive repeat biopsy; GS: Gleason score;
Indolent PCa: clinical stage T1c, PSA density < 0.15, Gleason score biopsy ≤ 6, percent of positive cores ≤ 33%

Reviewed by

Prof. H. van Poppel

Editorial comment

This is an important confirmatory study on the clinical use of PCA3 to guide the indication for a repeat biopsy that has demonstrated the clinical significance of this test. As shown previously there is no relation to prostate size but there is a correlation with tumour stage and grade and even in HGPIN the PCA3 score was significantly higher. Therefore PCA3 testing will be helpful in counselling patients that are candidates for a repeat biopsy.

A favourable PCA3 score below 35 or even below 10 will still not exclude the presence of cancer, not even of a significant cancer but the chance of finding this is low. Therefore patients can argue and still want to have another set of biopsies but one needs to realise that also negative biopsies cannot exclude the presence of (mostly insignificant) cancer.

More information
http://www.ncbi.nlm.nih.gov/pubmed/18602209?ordinalpos=2&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_RVDocSum