Patient Benefits of Radical Prostatectomy in Certified Prostate Cancer Centers: Comparative Results from the Multicenter IMPROVE Study

Abstract

Introduction: We investigated differences in treatment outcomes following radical prostatectomy (RP) between certified centers (CCs) and noncertified centers (nCCs) within the IMPROVE study group. Methods: A validated survey assessing various factors, including stress urinary incontinence (SUI) and decision regret (DR), was administered to 950 patients who underwent RP across 19 hospitals (12 CCs and 7 nCCs) at a median follow-up of 15 months after RP (interquartile range: 11–20). The response rate was 74%, with 703 patients participating, including 480 (68%) from CCs. Multivariate binary regression models were used to analyze differences between CCs and nCCs regarding the following binary endpoints: nerve-sparing (NS), positive surgical margins (PSM), SUI (defined as >1 safety pad), complications based on the Clavien-Dindo classification (grade ≥1, grade ≥3) and DR (>15 points indicating critical DR). Results: Considering the multivariate analysis, the rate of NS surgery was lower in CCs than in nCCs (OR = 0.52; p = 0.004). No significant differences were observed in the PSM rate (OR = 1.67; p = 0.051), SUI (OR = 1.03; p = 0.919), and DR (OR = 1.00; p = 0.990). SUI (OR 0.39; p < 0.001) and DR (OR 0.62; p = 0.026) were reported significantly less frequently by patients treated with robotic-assisted RP, which was significantly more often performed in CCs than in nCCs (68.3% vs. 18%; p < 0.001). The total complication rate was 45% lower in CCs (OR = 0.55; p = 0.004), although the number of complications requiring intervention (Clavien-Dindo classification ≥3) did not differ significantly between CCs and nCCs (OR = 2.52; p = 0.051). Conclusion: Within the IMPROVE study group, similarly favorable outcomes after RP were found in both CCs and nCCs, which, however, cannot be transferred to the general treatment landscape of PCA in Germany. Of note, robotic-assisted RP was more often performed in CCs and associated with less SUI and DR, while open prostatectomy was the treatment of choice in low-volume nCCs. Future prospective and region wide studies should also investigate the surgeon caseload and experience as well as a spillover effect of the certification process on nCCs.