PTEN loss with ERG-Negative Status is Associated with Lethal Disease after Radical Prostatectomy
Menée à partir de l'analyse immunohistochimique d'échantillons tumoraux issus de 791 patients atteints d'un cancer de la prostate de stade localisé traité par prostatectomie radicale (durée médiane de suivi : 12,8 ans), cette étude met en évidence une association entre l'absence d'expression intratumorale des gènes PTEN et ERG et le risque de décès par cancer de la prostate après le traitement
Purpose: Few studies have investigated the combined effects of PTEN loss and ERG expression on outcomes of metastasis or death from prostate cancer (PCa) in surgically treated patients. Here, we examined the association of PTEN/ERG status with lethal PCa in patients treated with radical prostatectomy (RP).
Materials and Methods: We included 791 patients with clinically localized PCa treated with RP at a single institution. Genetically validated immunohistochemistry (IHC) assays for PTEN and ERG were performed on tissue microarrays. Multivariable Cox proportional hazard models assessed the association of PTEN/ERG status with lethal PCa (defined as metastasis or PCa-specific death), adjusting for age, race, pathologic grade and stage, and surgical margin status.
Results: Median follow up for the cohort was 12.8 years. Twenty-five percent of cases (203/791) demonstrated PTEN loss, and 43% (330/776) were ERG-positive. On multivariable analysis, PTEN loss (HR 1.9, 95% CI 1.2–3.0, p=0.012) but not ERG expression (HR 0.6, 95% CI 0.4–1.1, p=0.11) was associated with increased risk of lethal PCa. The association of PTEN loss with lethal disease only remained among men with ERG-negative tumors (HR 2.3, 95% CI 1.3–4.1, p=0.005) and not ERG-positive tumors (HR 1.1, 95% CI 0.6–2.1, p=0.81).
Conclusions: PTEN loss is associated with an increased risk of lethal PCa after RP, and this risk is most pronounced in the subgroup of patients with ERG-negative tumors. This work corroborates the use of PTEN and ERG status for risk stratification in surgically treated patients.
Journal of Urology , résumé, 2018