Nephron-sparing Surgery for Pediatric Renal Tumors After Centralization of Pediatric Oncology Care in the Netherlands: Improved Outcomes With 3D Modeling

Background and aim: In this retrospective single center cohort study, we report the surgical outcomes of nephron-sparing surgery (NSS) for Wilms' tumor (WT) patients since centralization of pediatric oncology care in the Netherlands, and implementation of technological advancements. Therewith we describe the influence of experience and innovations for this type of surgery.

Methods: We retrospectively assessed all NSS procedures from January 1st 2015 until January 1st 2024 for patients who underwent surgery for a renal tumor at the Princess Máxima Center for Pediatric Oncology. Data were gathered on patient characteristics, diagnostic information, radiological characteristics, surgical technique and use of innovations, postoperative outcome, administered treatment and surgical follow-up.

Results: 36 patients (58 % female, 42 % male) were included with a total of 43 NSS procedures. Mean (SD) age at diagnosis was 33.3 (23.1) months. 16 procedures were performed without 3D models, of which 3 (18.8 %) resulted in an unexpected positive margin. 27 procedures were preoperatively planned with a 3D model with one (3.7 %) unexpected anticipated positive margins (p = 0.101). Six (13.9 %) procedures had post-operative complications including five urine leakages, one chyle leakage and two (reversible) acute kidney insufficiency. Four patients received a re-intervention (JJ-stent or drain).

Conclusions: In this retrospective single center cohort study, we show a good surgical outcome after NSS for children with renal tumors after the implementation of 3D models. This study can act as a baseline cohort to harmonize preoperative assessment, intraoperative technique and implementation of innovative surgical technology for further expansion of NSS for WT patients.