Urinary TMPRSS2:ERG and PCA3 in an active surveillance cohort: results from a baseline analysis in the Canary Prostate Active Surveillance Study
Menée sur une cohorte de 387 hommes atteints d'un cancer de la prostate sous surveillance active, cette étude multicentrique analyse l'association entre les niveaux urinaires de l'ARN messager du gène PCA3 ou du gène de fusion TMPRSS2-ERG et le volume ou le grade tumoral
Purpose: Active surveillance is used to manage low risk prostate cancer. Both PCA3 and TMRPSS2-ERG are promising biomarkers that may be associated with aggressive disease. This study examines the correlation of these biomarkers with higher cancer volume and grade determined at the time of biopsy in an active surveillance cohort. Experimental Design:Post-DRE urine was collected prospectively as part of the multi-institutional Canary Prostate Active Surveillance Study (PASS). PCA3 and TMPRSS2-ERG levels were analyzed in urine collected at study entry. Biomarker scores were correlated to clinical and pathologic variables. Results: In 387 men, both PCA3 and TMPRSS2-ERG scores were significantly associated with higher volume disease. For a negative repeat biopsy, and 1-10%, 11-33%, ≥34% positive cores, median PCA3 and TMPRSS2-ERG scores increased incrementally (P < 0.005). Both PCA3 and TMPRSS2-ERG scores were also significantly associated with presence of high grade disease. For a negative repeat biopsy, Gleason 6 and Gleason ≥7 cancers, the median PCA3 and TMPRSS2-ERG scores also increased incrementally (P = 0.02 and P = 0.001, respectively). Using the marker scores as a continuous variables, the odds ratio for a biopsy in which cancer was detected versus a negative repeat biopsy (ref) on modeling was 1.41 (95% CI 1.07-1.85), P = 0.01 for PCA3 and 1.28 (95% CI 1.10-1.49), P = 0.001 for TMPRSS2-ERG. Conclusions:For men on active surveillance both PCA3 and TMPRSS2-ERG appear to stratify risk of having aggressive cancer as defined by tumor volume or Gleason score.
Clinical Cancer Research , résumé, 2013