Parallel Meeting on Wednesday 17, June 2026, 15:10 - 15:55
15:10 - 15:15
S05-1 (VP)
Grégoire SCHNEIDER 1, Celine GROSOS 2, Tudor ENACHE 1, Jeanne GOULIN 1, Philippe PAPAREL 3, Benoit DUMONT 4, Cécile PICARD 5, Delphine DEMEDE 1, Guillaume ROSSIGNOL 1, Valeska BIDAULT 1 and Frederic HAMEURY 1
1) Hopital Femme Mère Enfant, Hospices Civils de Lyon, Department of Pediatric Surgery and Urology, Lyon, FRANCE - 2) Hôpital Femme Mère Enfant, Hospices Civils de Lyon, Department of Pediatric Surgery and Urology, Lyon, FRANCE - 3) Hôpital Lyon , Hospices Civils de Lyon, Urologic Surgery, Lyon, FRANCE - 4) IHOPe, Centre Léon Berard, Pediatric Oncology, Lyon, FRANCE - 5) Hospices Civils de Lyon, Pathology, Lyon, FRANCE
PURPOSE
Partial nephrectomy is increasingly considered for selected non-syndromic Wilms tumours when oncological safety can be ensured. This video illustrates how intraoperative ultrasound and 3D planning strengthen the safety of robot-assisted partial nephrectomy in this setting. Intraoperative ultrasound—still rarely used in paediatric cases—helps precisely define resection planes and supports real-time surgical decision-making. The video highlights the key technical steps and illustrates how these imaging tools facilitate safe and controlled tumour excision.
MATERIAL AND METHODS
A single clinical case is presented through an operative video, illustrating imaging tools, surgical strategy, and technical tips.
RESULTS
This case involves a 3-year-9-month-old, 19-kg boy presenting with a localized right upper-pole renal mass. He received 4 weeks of preoperative chemotherapy according to the UMBRELLA protocol. Preoperative 3D CT reconstruction enabled precise assessment of the upper-pole lesion (77 × 72 × 72 mm; 210 mL) and confirmed the feasibility of partial nephrectomy. Despite the tumour size and its close relationship with major vascular structures, a robot-assisted nephron-sparing procedure was planned.
During surgery, an ultrasound probe (ROB12C4, GE) was introduced through a 12-mm trocar and easily manipulated with a robotic grasper to define the parenchymal transection line. The video details the standardized operative strategy: complete renal mobilization, hilar control, ultrasound-guided identification of the resection plane, hilar clamping, tumour excision with parenchymal and calyceal transection, and reconstruction using self-locking sutures. The procedure proceeded uneventfully, with negligible blood loss, and the patient was discharged on postoperative day X4.
Histopathological analysis confirmed a nephroblastoma with clear surgical margins and an estimated 50% of functional renal tissue preserved. At 6-month follow-up, the patient remained in complete remission, with good preservation of the lower renal pole.
CONCLUSIONS
This video demonstrates that robotic partial nephrectomy can be safely performed in selected paediatric Wilms tumours using intraoperative ultrasound, 3D segmentation, and a standardized surgical workflow.
15:15 - 15:18
S05-2 (CP)
Marcela PYCHOVA 1, Karel SVOJGR 2, Karel PYCHA 1, Silvia DOBRANSKA 2, Jaromir HACEK 3, Josef MALIS 2, Martin KYNCL 4, Lucie SRAMKOVA 2 and Michal RYGL 1
1) Second Faculty of Medicine Charles University and Motol University Hospital, Department of Paediatric Surgery, Prague, CZECH REPUBLIC - 2) Second Faculty of Medicine Charles University and Motol University Hospital, Department of Paediatric Haematology and Oncology, Prague, CZECH REPUBLIC - 3) Second Faculty of Medicine Charles University and Motol University Hospital, Department of Pathology and Molecular Medicine, Prague, CZECH REPUBLIC - 4) Second Faculty of Medicine Charles University and Motol University Hospital, Department of Radiology, Prague, CZECH REPUBLIC
PURPOSE
The aim of the study is to evaluate oncological and renal outcomes in children with bilateral Wilms tumor (BWT) treated with nephron-sparing surgery (NSS) whenever technically feasible, and to assess whether partial tumor resection provides safe and effective long-term survival.
MATERIAL AND METHODS
We performed a retrospective review of all patients with BWT treated at our institution between January 2000 and December 2024 according to the SIOP 2001 and SIOP–RTSG Umbrella 2016 protocols. Clinical, radiological, operative and follow-up data were extracted from electronic medical records. Variables included demographics, tumour characteristics, treatment modality, surgical margins, renal function, recurrence and survival. All data were entered into structured Excel spreadsheets and cross-validated for accuracy. Survival analysis (event-free survival [EFS] and overall survival [OS]) was conducted using the Kaplan–Meier method. The primary endpoint was long-term OS, secondary endpoints included EFS, renal preservation, and incidence of chronic kidney disease (CKD) or end-stage renal disease (ESRD).
RESULTS
Twenty-two patients (11 female / 11 male) with bilateral nephroblastoma were identified. Median age at diagnosis was 2.21 years (0.3–6.62). Four children (18%) had a recognised predisposition syndrome. Twenty-one patients presented with synchronous tumours, one developed a metachronous tumour. Preoperative chemotherapy was administered to 19 patients (86%), three (14%) underwent primary surgery. Adequate normal renal parenchyma was preserved at the time of surgery in all cases. Bilateral tumour-directed resections were performed in eight patients, the remaining underwent unilateral nephrectomy combined with contralateral NSS. Four patients with microscopically positive margins after NSS received adjuvant radiotherapy; all survived. The mean follow-up was 11.5 years (1.9–22.8). Kaplan–Meier estimates demonstrated an EFS of 59.1% and OS of 86.4%. Two patients developed acute renal failure requiring dialysis during treatment and subsequently died from tumour recurrence. Two patients with Denys–Drash syndrome progressed to ESRD and underwent kidney transplantation. One additional patient required transplantation in adulthood. All remaining survivors maintain normal renal function.
CONCLUSIONS
NSS in bilateral Wilms tumour, even when postoperative microscopic residue persists after preoperative chemotherapy, provides high overall survival with preservation of renal function. These findings support nephron-sparing approaches as a safe and effective strategy in BWT.
15:18 - 15:21
S05-3 (CP)
Ugo Maria PIERUCCI 1, Thibault PLANCHAMP 2, Dominique BERREBI 3, Lauriane LEMELLE 4, Daniel ORBACH 5, Nicolas NAYLA 6, Claire DAGORNO 2, Alaa EL GHONEIMI 2, Pascale PHILIPPE-CHOMETTE 2 and Matthieu PEYCELON 2
1) University Hospital Robert-Debré and Buzzi Children's Hospital, Department of Pediatric Surgery and Urology, National Reference Centre for Rare Urinary Tract Malformations (MARVU), ERN eUROGEN accredited center, Milan, ITALY - 2) University Hospital Robert-Debré, Department of Pediatric Surgery and Urology, National Reference Centre for Rare Urinary Tract Malformations (MARVU), ERN eUROGEN accredited center, Paris, FRANCE - 3) Hôpital Necker-Enfants Malades, Department of Pathology, AP-HP. Centre-Université Paris Cité, Paris, FRANCE - 4) Institut Curie, SIREDO Oncology Center (Care, Innovation and Research for Children and AYA with Cancer), PSL Research University, Paris, FRANCE - 5) Institut Curie, SIREDO Oncology Center - Care, Innovation and Research for Children and AYA with Cancer - PSL Research University, Paris, FRANCE - 6) Institut Curie, Department of Imaging, Paris, FRANCE
PURPOSE
Minimally invasive surgery (MIS) is increasingly used in pediatric oncology, but evidence supporting robotic-assisted surgery (RAS) for Wilms’ tumor (WT) remain limited. Current international guidelines still list several formal contraindications to MIS. This study reports the preliminary experience of a tertiary referral center performing RAS for WT, including in children with criteria traditionally considered unsuitable for MIS.
MATERIAL AND METHODS
A retrospective review was conducted of all pediatric patients who had RAS for histologically confirmed WT(2020-2024). Perioperative, oncological, and follow-up outcomes were evaluated. Subgroup analysis compared patients with versus without formal MIS contraindications according to SIOP–UMBRELLA 2016 criteria. Statistical analysis: descriptive and univariate comparison.
RESULTS
Nineteen children had RAS during the study period. Median age at diagnosis was 55.0 months(IQR:17–80). Most tumors were unilateral(89%), and74% received preoperative chemotherapy. Median (IQR) tumor volume decreased from 503.0 mL(35–940) at diagnosis to 220.5 mL(31–506 mL) after chemotherapy(median regression: 44.5%). Seventeen patients had radical nephrectomy, one partial nephrectomy, and one tumorectomy. Median operative time was 265 minutes. Lymphadenectomy was performed in 95% of cases (median (IQR):3nodes(2–3)). Only one conversion occurred (5%). Two postoperative complications were observed (Clavien–Madadi IB and IIIA), with no intraoperative adverse events. Final pathology revealed Stage I disease in 74% and intermediate-risk histology in 79%. Two patients experienced distant metastatic relapse (one hepatic, one pulmonary), both successfully treated. At a median (IQR) follow-up of 32.0 months(11.0-38.0), all patients were alive without long-term surgical sequelae. One-and three-year overall survival rates were 100%, event-free survival rates were 94.7% and 89.5%, respectively. Subgroup analysis showed that 6 patients(32%) had one or more formal SIOP–UMBRELLA-MIS contraindications (large tumor volume, vertebral extension, limited chemotherapy response). Despite longer operative(335vs250 min; p=0.001) time and length of stay (4.5vs.3.0 days; p=0.037) [PM1] in this subgroup, no significant differences were observed in complications (1(17%)vs .(8%);p 0.99), conversion (0(17%)vs1(8%);p=0.99), ), margin positivity (1(17%)vs.3 (23%); p=0.99), or recurrence (1(17%)vs.1(8%);p=0.99).
CONCLUSIONS
Robotic-assisted surgery for Wilms’ tumor appears feasible and safe in carefully selected patients, including some with traditional MIS contraindications. These preliminary results suggest that the indications for RAS may be broader than currently recommended.
15:33 - 15:37
S05-4 (BSP)
Osanna KOSOYAN 1, Valentina VILLANI 1, Sean MONJI 1, Aditya DESAI 1, Astgik PETROSYAN 1, Valter LONGO 2, Stefano DA SACCO 1 and Laura PERIN 1
1) Children's Hospital Los Angeles, Urology, Los Angeles, USA - 2) University of Southern California, Los Angeles, USA
PURPOSE
Wilms tumor (WT) is the most common renal malignancy in childhood, presenting therapeutic challenges, especially for patients with relapsed or high-risk aggressive forms. While current dietary approaches address malnutrition in cancer patients, they do not target tumor growth. Preclinical data show that a fasting-mimicking diet (FMD) delays tumor progression and reduces chemotherapy toxicity in different cancers. Here, we study the role of the FMD in WT.
MATERIAL AND METHODS
Using different in vitro and in vivo tools, we characterized the WT cancer stem cells (WT-CSC). We designed a starvation protocol (STS) and performed proliferation and viability assays on WT-CSC. We performed western blot, knockdown experiments, and bulk RNA-seq study to the mechanisms of action of the STS. We also performed time-course chemoresistance experiments to determine the synergic effects of the STS+ drugs in reducing self-renewal in WT-CSC.
RESULTS
WT-CSC are self-renewing, chemoresistant, generate xenografts that recapitulate the original tumor, and can also metastasize. WT-CSC exposed to STS showed reduced viability and proliferation and a significant reduction in IGF1-R, p-AKT/AKT, and p-p70S6K/p70S6K, and a reduction of CITED1 and SIX2, the master genes regulating self-renewal in these cells. Bulk RNA-seq revealed significant gene expression changes in WT-CSCs at both the end of STS and 1 week post-refeeding, revealing a downregulation of pathways including ABC-type transporters, cell cycle processes, and apoptosis. KD studies confirmed the direct AKT-mediated regulation of β-catenin in modulating WT-CSC. When vincristine and actinomycin-D are applied in combination with the STS, the proliferation and self-renewal are highly diminished compared to the drugs alone.
CONCLUSIONS
Our data suggest that FMD impairs WT-CSC self-renewal by downregulating the IGF1 signaling and downstream targets and that its combination with chemo-drugs decreases survival and proliferation of WT-CSC. Our results provide new knowledge into key factors critical to the development of WT and will set the foundation for investigating the effects of FMD on this pediatric renal cancer. The benefits of the FMD, a safe and accessible therapy, would have a tremendous medical and societal impact on these kids.
15:37 - 15:40
S05-5 (CP)
Irene DIEZ BARTOLOMÉ, María Victoria LÓPEZ CANELADA, Carla RAMÍREZ AMORÓS, Virginia AMESTY MORELLO, Susana RIVAS VILA, Roberto LOBATO ROMERA, Pedro LÓPEZ PEREIRA and María José MARTÍNEZ URRUTIA
Hospital Universitario La Paz, Paediatric urology, Madrid, SPAIN
INTRODUCTION
A minority of patients with Wilms tumor (WT) present intravascular extension at diagnosis, which challenges treatment and prognosis. Our objective was to retrospectively analyze the clinical characteristics, surgical management, and outcomes of of patients with WT and intravascular invasión treated at our center over the past 30 years.
MATERIAL AND METHODS
We included patients with WT and intravascular involvement who received neoadjuvant chemotherapy according to SIOP protocol. Tumor characteristics, extent of vascular involvement, response to chemotherapy, surgical approach, pathological findings, postoperative complications, recurrence, and mortality were evaluated. Survival was assessed using Kaplan-Meier curves and the log-rank test (p < 0.05 considered significant).
RESULTS
Among 153 patients with WT, 18(12.4%) presented intravascular invasion. The median age at diagnosis was 4(2-12). A palpable abdominal mass was the presenting sign in 55.5% of cases. Tumors were located on the right kidney in 10 patients(55.5%), and bilateral involvement occurred in 2(11.1%). According to Daum's classification, intravascular extension was type I in 3/18, II in 6/18, III in 4/18, and IV in 6/18 patients. Seven patients(38.9%) had metastatic disease, involving liver and/or lungs. After chemotherapy, tumor size decreased in 10 patients(55.5%), and complete disappearance of the thrombus occurred in 2(11.1%).
All patients underwent nephroureterectomy, with thrombectomy performed in 16(88.9%) who had residual thrombus; the two bilateral cases(11.1%) required contralateral partial tumorectomy. Hepatic vascular exclusion was used in 10 patients(55.5%), cardiopulmonary bypass in 4(22.2%), and cavotomy in 16(88.8%). Thrombus resection was incomplete in 2 patients(11.1%). Histology revealed a predominance of stromal components(48%). Tumor risk groups were low in 3 patients(16.7%), intermediate in 12(66.7%), and high in 3(16.7%). Viable tumor cells were identified within the thrombus in 12 patients(66.7%). Postoperative complications included bowel obstruction in 2 cases and inferior vena cava stenosis in 1. Three patients(16.7%) developed recurrence, and 3(15.8%) died. No significant differences in survival were observed according to tumor viability or completeness of resection (log-rank p > 0.05).
CONCLUSIONS
The presence of viable cells within the thrombus or incomplete resection did not appear to significantly affect overall survival. Our findings highlight the importance of careful surgical planning and multidisciplinary management.
15:40 - 15:43
S05-6 (CP)
Hyomyoung LEE, Jae Jin LEE, Kwanjin PARK and Young Jae IM
Seoul National University Children's Hospital, Seoul, Republic of Korea, Department of Pediatric Urology, Seoul, REPUBLIC OF KOREA
PURPOSE
Current guidelines for the management of unilateral non-syndromic Wilms’ tumor (NSWT) advocate for radical nephrectomy. However, concerns persist that the consequent reduction in nephron mass and glomerular filtration rate may predispose patients to the onset and rapid progression of chronic kidney disease. This study evaluated long-term renal function outcomes in survivors of NSWT who underwent unilateral nephrectomy with adjuvant therapy.
MATERIAL AND METHODS
This retrospective study included patients with NSWT treated with unilateral nephrectomy and standard adjuvant therapy, at Seoul National University Children’s hospital between March 2016 and June 2022. Patients with bilateral or syndromic WT, incomplete clinical data or less than three years of follow-up were excluded. Primary outcome was the change in estimated glomerular filtrateion rate (eGFR) from preoperative to 3 years postoperatively. Secondary outcomes were the predictors associated with postoperative renal function decline.
RESULTS
A total of 26 patients were identified. Median age was 3.0 years (IQR, 1.3–4.0) and median follow-up duration was 6.6 years (IQR, 4.6–8.1). Median preoperative eGFR was 93.8 mL/min/1.73 m² (IQR, 84.6–134.8), and 61.5% were classified as chronic kidney disease (CKD) stage 1. Stage 1 Wilms tumor was the most common (34.6%). All patients received adjuvant chemotherapy, while 65.4% received neoadjuvant chemotherapy and 19.2% underwent radiotherapy. Median eGFR declined significantly from 93.8 (84.6–134.8) to 82.7 mL/min/1.73 m² (73.9–90.3) at 3 years postoperatively/. At that time, 61.5% were classified as CKD stage 2 and 11.5% as CKD stage 3, with no progression to CKD stage 4 or 5. Hypertension was observed in 38.5%, and no cases of proteinuria were identified. No significant clinical, tumor-related, or treatement-related predictors of stage 3 CKD were found.
CONCLUSIONS
Patients with NSWT showed a significant decline in eGFR over the 3 years following nephrectomy. However, most remained within CKD stages 1–2. Hypertension was common at 3 years postoperatively. No clear predictors of CKD stage 3 were identified. These findings emphasize the need for structured long-term monitoring of renal function and blood pressure in Wilms tumor survivors.