Evaluation of short term surgical outcomes of radical prostatectomy in the decade following the introduction of minimum volume standards in the Netherlands

Introduction: A minimum volume standard (MVS) of 20 radical prostatectomies (RPs) per institution per year was implemented in the Netherlands in 2014, and raised to 50 RPs in 2018 and 100 in 2019. This study aimed to evaluate the effects of implementing a MVS on the extent of care centralization and short term surgical outcomes. Methods: All patients who underwent RP between 2014 and 2022 were identified in the nationwide Netherlands Cancer Registry. Short term surgical outcomes included positive surgical margins (PSMs), PSA persistence (failure to achieve a PSA value <0.1 ng/mL within 6 months after RP) and complications (Clavien-Dindo grade ≥3) up to 30 days after RP. Multivariable logistic regression analyses were performed to evaluate surgical outcomes over time. Results: Between 2014 and 2022, 24,576 RPs were performed and the number of hospitals performing RPs decreased substantially from 40 in 2014 to 14 in 2022, whereas the median number of RPs per hospital per year increased from 85 (IQR: 57–139) to 189 (IQR: 157–393). PSM-rate decreased from 51.6% to 45.7% for pT3-4 (OR = 0.95, 95% CI 0.93–0.98) and 23.6% to 17.6% for pT2 (OR = 0.93, 95% CI 0.91–0.96) prostate cancer. A decline was observed in PSA persistence from 14.0% to 7.7% (OR = 0.84, 95% CI 0.82–0.87). Also the grade ≥3 complication-rate slightly decreased from 3.9% to 3.0% (OR = 0.94, 95% CI 0.90–0.98). Conclusion: Introduction of a MVS resulted in a substantial centralization of RP-care in the Netherlands. A gradual, but moderate, improvement was observed in complications, PSMs and PSA persistence after RP.