External Validation of the European Association of Urology Biochemical Recurrence Risk Groups to Predict Metastasis and Mortality After Radical Prostatectomy in a European Cohort

Abstract

The impact of biochemical recurrence (BCR) after radical treatment of prostate cancer on oncological outcomes remains unclear. A new European Association of Urology BCR risk stratification (low and high risk) has been proposed. To validate these risk groups, we retrospectively analyzed data for 1125 post-radical prostatectomy (RP) BCR patients (surgery between 1992 and 2006). Univariable Kaplan-Meier plots and multivariable Cox regression models with time-dependent covariates were used to test the independent predictor status of the risk grouping on metastatic progression (MP) and prostate cancer-specific mortality (PCSM). The 5-yr MP-free and PCSM-free survival rates were significantly higher among patients with low BCR risk compared to their high-risk counterparts. In multivariable analyses, the BCR risk grouping reached independent predictor status for MP (hazard ratio [HR] 3.46; p<0.001) and PCSM (HR 5.12; p<0.001). Salvage radiation therapy, especially when delivered at prostate-specific antigen <0.5ng/ml, was highly protective. Our findings corroborate the validity of this novel BCR risk grouping, which is easily applicable in daily practice and could be valuable in decision-making for salvage therapy and clinical trials. PATIENT SUMMARY: The European Association of Urology grouping for the risk of biochemical recurrence of prostate cancer after radical prostatectomy was valid when applied in a European study cohort.

Keywords: Biochemical recurrence; European Association of Urology; Prostate cancer; Radical prostatectomy; Risk groups; Survival.