Late Health Outcomes Among Survivors of Wilms Tumor Diagnosed Over Three Decades: A Report From the Childhood Cancer Survivor Study

Nephron-Sparing Surgery for Patients With Wilms Tumor, a Surgical Delphi Study Consensus Statement

BACKGROUND AND AIM

Current pediatric renal tumor treatment protocols allow for nephron-sparing surgery (NSS) for unilateral disease only under strict conditions. Oncological guidelines do not account for surgical feasibility, however, possibly reducing the utilization of NSS. To potentially change this, a definition of surgical feasibility is required. This study aimed to define surgical consensus statements for the assessment of patients with Wilms tumor (WT) for NSS.

METHODS

A Delphi study was performed inviting 34 potential experts. Surgeons were asked to answer the questionnaires without considering their current treatment protocol. The first questionnaire contained five open-ended questions regarding surgery, oncology, contraindications for NSS, technique, and organization. Follow-up questionnaires contained closed-ended statements based on previous answers.

RESULTS

Eleven surgeons were included in the expert panel and continued with three follow-up questionnaires containing 72 statements in total. A median of seven (3 minimum to 10 maximum) NSS procedures were performed per year in the hospitals of the experts. NSS for nonsyndromic unilateral WT patients can be surgically considered if they receive 4 weeks of neoadjuvant chemotherapy, have a preoperative tumor volume of less than 200 mL, and if partial nephrectomy with wide resection margin (>5 mm) can be performed. In keeping with organizational guidelines, among COG surgeons, NSS was not advocated for patients with nonsyndromic unilateral WT.

CONCLUSIONS

Using a Delphi method, surgical experts defined consensus statements regarding NSS for patients with WT to define surgical feasibility in future treatment protocols and expand the utilization of oncologically appropriate NSS.

Current surgical approaches to pediatric renal tumors

Pediatric renal tumors are among the most common pediatric solid malignancies. Surgical resection is a key component in the multidisciplinary therapy for children with kidney tumors. Therefore, it is imperative that surgeons caring for children with renal tumors fully understand the current standards of care in order to provide appropriate surgical expertise within this multimodal framework. Fortunately, the last 60 years of international, multidisciplinary pediatric cancer cooperative group studies have enabled high rates of cure for these patients. This review will highlight the international surgical approaches to pediatric patients with kidney cancer to help surgeons understand the key differences and similarities between the European (International Society of Pediatric Oncology) and North American (Children's Oncology Group) recommendations.

Dictation Precision: Evaluating Paediatric Oncology Operative Reports as an Impetus for Synoptic Reports

PURPOSE

The purpose of this study was to audit paediatric surgical oncology dictations to evaluate completeness and ease of data collection and provide a baseline measurement for the implementation of synoptic operative reports (SORs) in a tertiary care setting.

METHODS

An audit tool based on Children's Oncology Group (COG) protocols was created to assess the completeness of surgical and tumour-specific data within operative reports. Audited cases included four paediatric tumours of interest (Germ Cell, Wilms, Neuroblastoma, and Hepatoblastoma) between 2010 and 2023.

RESULTS

Overall, 71 audits were performed, the majority being Wilms Tumour cases (45.1 %), followed by Neuroblastoma (29.6 %), Germ Cell (18.3 %), and Hepatoblastoma (7.0 %). The average percentage of complete data for operative reports was low; the mean completeness of general oncological information for all tumour types was 66.0 %, and tumour-specific details were 42.0 %. Ovarian Germ Cell Tumour had the highest average percentage of complete data (65.9 %), followed by Wilms Tumour (58.7 %), Testicular Germ Cell Tumour (43.0 %), Neuroblastoma (15.0 %), and Hepatoblastoma (9.5 %). The median data collection time was 6.0 min per audit. The median time from the operation to the transcription of the report was 1.0 days (interquartile range (IQR): 1.0-7.0).

CONCLUSION

Narrative operative reports have inadequate completeness, especially concerning tumour-specific factors, which are often essential in accurate diagnosis, and in guiding treatment for children with cancer. SORs could be a solution and aid in the completeness and accessibility of data use.

TYPE OF STUDY

Retrospective review.

LEVEL OF EVIDENCE (I-V)

IV.

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.

The incidence and outcome of acute kidney injury during pediatric kidney tumor treatment-a national cohort study

BACKGROUND

Acute kidney injury (AKI) is a serious complication of pediatric cancer treatment that is suggested to increase the risk of chronic kidney disease (CKD). Children with a kidney tumor may be at particular risk. This study aimed to determine the incidence and risk factors of AKI and its association with CKD during pediatric kidney tumor treatment.

METHODS

We analyzed data from a prospective national cohort of patients ≤ 18 years old diagnosed with a kidney tumor between 2015 and 2021 in the Princess Máxima Center for Pediatric Oncology in the Netherlands. AKI was defined according to KDIGO criteria. CKD was assessed 1 year post-treatment based on proteinuria and/or decreased estimated glomerular filtration rate (eGFR).

RESULTS

Of 147 patients, we observed AKI in 104 patients (71%) during therapy. AKI occurred most often within 48 h after tumor nephrectomy (88/104), while the rest had non-nephrectomy-related AKI from multifactorial causes. Sixteen patients experienced more than one AKI episode, and 92/104 episodes were reversible. Patients who developed AKI had a higher eGFR prior to surgery compared to those who did not develop AKI. CKD was observed in 16/120 patients (13%). Risk factors for developing CKD included the occurrence of at least 1 AKI event, the use of a > 3-drug regimen, and a lower eGFR at the start of treatment.

CONCLUSION

The high incidence of AKI and its association with early CKD highlights the need for early detection, prevention, and intervention strategies during pediatric kidney tumor treatment.

Race and Ethnic Group Enrollment and Outcomes for Wilms Tumor: Analysis of the Current Era Children's Oncology Group Study, AREN03B2

BACKGROUND

To review race and ethnic group enrollment and outcomes for Wilms tumor (WT) across all 4 risk-assigned therapeutic trials from the current era Children's Oncology Group Renal Tumor Biology and Risk Stratification Protocol, AREN03B2.

STUDY DESIGN

For patients with WT enrolled in AREN03B2 (2006 to 2019), disease and biologic features, therapeutic study-specific enrollment, and event-free (EFS) and overall (OS) 4-year survival were compared between institutionally reported race and ethnic groups.

RESULTS

Among 5,146 patients with WT, no statistically significant differences were detected between race and ethnic groups regarding subsequent risk-assigned therapeutic study enrollment, disease stage, histology, biologic factors, or overall EFS or OS, except the following variables: Black children were older and had larger tumors at enrollment, whereas Hispanic children had lower rates of diffuse anaplasia WT and loss of heterozygosity at 1p. The only significant difference in EFS or OS between race and ethnic groups was observed among the few children treated for diffuse anaplasia WT with regimen UH-1 and -2 on high-risk protocol, AREN0321. On this therapeutic arm only, Black children showed worse EFS (hazard ratio = 3.18) and OS (hazard ratio = 3.42). However, this finding was not replicated for patients treated with regimen UH-1 and -2 under AREN03B2 but not on AREN0321.

CONCLUSIONS

Race and ethnic group enrollment appeared constant across AREN03B2 risk-assigned therapeutic trials. EFS and OS on these therapeutic trials when analyzed together were comparable regarding race and ethnicity. Black children may have experienced worse stage-specific survival when treated with regimen UH-1 and -2 on AREN0321, but this survival gap was not confirmed when analyzing additional high-risk AREN03B2 patients.

MRI-based inter- and intrafraction motion analysis of the pancreatic tail and spleen as preparation for adaptive MRI-guided radiotherapy in neuroblastoma

BACKGROUND

In pediatric radiotherapy treatment planning of abdominal tumors, dose constraints to the pancreatic tail/spleen are applied to reduce late toxicity. In this study, an analysis of inter- and intrafraction motion of the pancreatic tail/spleen is performed to estimate the potential benefits of online MRI-guided radiotherapy (MRgRT).

MATERIALS AND METHODS

Ten randomly selected neuroblastoma patients (median age: 3.4 years), irradiated with intensity-modulated arc therapy at our department (prescription dose: 21.6/1.8 Gy), were retrospectively evaluated for inter- and intrafraction motion of the pancreatic tail/spleen. Three follow-up MRIs (T2- and T1-weighted ± gadolinium) were rigidly registered to a planning CT (pCT), on the vertebrae around the target volume. The pancreatic tail/spleen were delineated on all MRIs and pCT. Interfraction motion was defined as a center of gravity change between pCT and T2-weighted images in left-right (LR), anterior-posterior (AP) and cranial-caudal (CC) direction. For intrafraction motion analysis, organ position on T1-weighted ± gadolinium was compared to T2-weighted. The clinical radiation plan was used to estimate the dose received by the pancreatic tail/spleen for each position.

RESULTS

The median (IQR) interfraction motion was minimal in LR/AP, and largest in CC direction; pancreatic tail 2.5 mm (8.9), and spleen 0.9 mm (3.9). Intrafraction motion was smaller, but showed a similar motion pattern (pancreatic tail, CC: 0.4 mm (1.6); spleen, CC: 0.9 mm (2.8)). The differences of Dmean associated with inter- and intrafraction motions ranged from - 3.5 to 5.8 Gy for the pancreatic tail and - 1.2 to 3.0 Gy for the spleen. In 6 out of 10 patients, movements of the pancreatic tail and spleen were highlighted as potentially clinically significant because of ≥ 1 Gy dose constraint violation.

CONCLUSION

Inter- and intrafraction organ motion results into unexpected constrain violations in 60% of a randomly selected neuroblastoma cohort, supporting further prospective exploration of MRgRT.