Background and Aims

The Japan Children’s Cancer Group (JCCG) Neuroblastoma Committee (JNBSG) conducted the JN-I-10 for intermediate-risk patients using Image-defined risk factors (IDRFs) as the main factor for determining treatment. This sJN-I-10 is the first clinical trial on the efficacy of IDRF-based surgical decision and stepwise treatment intensification for patients with intermediate-risk neuroblastomas. In order to clarify the predictive capability of IDRFs for surgical complications in intermediate-risk neuroblastoma, we made surgical evaluation in JN-I-10.

Methods

Of the 61 patients enrolled in JN-I-10, 54 patients were eligible. Of these, 28 patients underwent surgery rather than biopsy. Four patients were excluded from the analysis due to lacking the precise information of surgery. Three patients underwent surgery rather than biopsy before neoadjuvant chemotherapy. Finally, 21 patients were selected and analyzed IDRFs in association with surgical complications.

Results

Three patients had localized tumor only and 18 patients had local and metastatic lesions. All patients were treated by neoadjuvant chemotherapy. Surgery rather than biopsy was performed after 2 to 9 courses of neoadjuvant chemotherapy. IDRFs were present in 18 patients at diagnosis and 11 patients preoperatively. Major surgical complications such as class III or IV intraoperative bleeding, major vascular injury, bowel obstruction, renal atrophy was observed in 7 patients. Of these, IDRFs were present in 7patients at diagnosis and 4 patients preoperatively. Regarding surgical complications, sensitivity and specificity of IDRFs was 100% and 21.4% at diagnosis, 57.1% and 57.1% preoperatively respectively.

Conclusions

Compared to the low-risk protocol JN-L-10, surgical complications were observed more frequently in the intermediate-risk patients (14.7% in low-risk, 33.3% in intermediate-risk). Surgery should be performed carefully in the patients with IDRFs at diagnosis, if IDRFs would decrease or disappeared by neoadjuvant chemotherapy.

Background and Aims

Ganglioneuromas (GNs) are rare benign peripheral neuroblastic tumors (PNTs). The primary treatment modality is surgical resection. We aimed to review our institutional experience with childhood GNs.

Methods

Hospital files of the children with PNTs between 1995 and 2021 were reviewed, and cases with the histopathological diagnosis of GN were identified. Data concerning demographic characteristics, clinical, laboratory, and radiological findings, image-defined risk factors (IDRF), INRG stages, diagnostic and surgical procedures, histopathological findings, and overall outcome were recorded.

Results

Of 668 cases with PNTs, 70 (10.4%) had GNs. The median age was 7.4 years (range, 2.6-15.7 years; 16/70 <5 years) (females/males, 41/29). Common presenting complaints were abdominal pain and cough; 33/70 cases were diagnosed incidentally. Primary tumor sites were the abdomen in 41/70, the thorax in 25/70, the neck in 3 cases, and the pelvis in one. Urinary HVA and VMA were elevated in 8 cases. The median tumor size was 6.5 cm (range, 1.4-17). Fifty cases (71.4%) with no IDRF were staged as INRG-L1; 20 cases with IDRF(s) (15 single, five >1) were staged as INRG-L2. Complete and partial tumor resections were performed in 58/70 and 6/70 cases, respectively (6 had no resection). The overall complication rate was 17.1% (11/64) (Horner syndrome 3, renal atrophy 2, leg hypoesthesia 2). At a median follow-up of 9 years (range, 0-27), 5 cases were lost to follow-up; 65 were alive. One patient with a gross tumor residue underwent total resection due to tumor progression 13 years after the initial surgery. Eleven other cases with gross residual tumors experienced no tumor progression in the follow-up.

Conclusions

GNs are benign PNTs, and most are free of IDRFs. Even with incomplete or partial resection, long-term outcomes are excellent. A multidisciplinary approach is necessary, and the decision of tumor resection should be made meticulously for each case.

Background and Aims

Ganglioneuroma (GN) and ganglioneuroblastoma intermixed (GNBi) classically follow a more benign clinical course than neuroblastoma (NB). Management can vary between surgical resection and conservative ‘ watch and wait ‘ surveillance. This study details management, complications and long term follow up of GN/GNBi comparing the outcomes of surgery versus surveillance.

Methods

Retrospective UK nationwide study including patients (aged 0-24 yrs) diagnosed with localized GN or GNBi from 1990-2020.

Results

Eleven of 17 UK CCLG centres participated in the study and 242 patients were included. Median age at presentation was 6.41 yrs (IQR: 3.88-11.09); median follow up 5.08 yrs. The majority were female (n=147, 61%). 51 (21%) patients were initially managed with active surveillance versus 191 (79%) with surgery. Patients who underwent surveillance were found to have more IDRFs than the surgery group (54% versus 38%; p=0.09). There was no significant difference(s) in tumour volume observed (109.8cm³ vs 108.1cm³; p=0.60).

Twenty patients (39%) underwent intervention after an initial period of observation (19 had surgery, 1 had cryoablation) due to clinical changes (i.e. increased size of the tumour, worsening/severe symptoms), parental anxiety or to confirm histopathology. The extent of tumour resection was comparable between the delayed and initial ‘up front’ surgery groups (77% vs 71% had >95% gross macroscopic resection).

Of 208 patients who underwent surgery, two patients died (1%) and three cases (1.4%) had significant morbidity (Clavien Dindo IIIa, IIIb or IV). 49 patients (24%) have ongoing symptoms (N=42 predate surgery). Overall, five patients died - 2 from surgery complications and 3 non tumour-related causes (one in surveillance group).

Conclusions

In this study most patients with GN/GNBi underwent ‘upfront’ surgical resection. Watchful surveillance may represent a safe approach in select patients with GN/GNBi and IDRFs. However, a significant proportion who were initially observed (39%) ultimately required surgery. Overall mortality (2%) in both groups remains low.

Background and Aims

Nephron sparing surgery (NSS) is a key surgical technique heading to preserve as much as possible kidney function while treating with strict oncological rules the different histological types of pediatric kidney tumours. NSS is a demanding technique usually performed by open surgery. Laparoscopy is of increasing use for total nephrectomy but has not yet been developed for NSS. The aim of our presentation is to describe a preliminary experience of laparoscopic NSS in pediatric kidney tumours.

Methods

Laparoscopy was intended for tumours located at one part of the kidney whatever their size or contact with calices but with respect to oncological indication of partial nephrectomy.

Results

Four patients (3 girls and one boy) aged from 3 to 11 years were operated on upfront for three of them (2 renal cell carcinoma and one epithelioid angiomyolipoma) and after neoadjuvant chemotherapy for one patient with Wilms tumour. Tumours were located at the right upper part of the kidney in two cases, in the lower part of the left kidney in 2 cases and measured a mean of 4 cm [2.7-6.3]. The surgical technique relied on a 10 mm 3D optic port and 2 or 3 working ports of 5 mm. The coagulation of the cut parenchyma was obtained with bipolar, coagulation device and parenchyma compression but no vascular clamping was needed. The mean operative time was 210 mn [120-265]. The calices were opened in two patients to assure good surgical margins and closed by sutures with resorbable stitches. The per and postoperative courses were uneventful. All patients are alive with good oncological outcome and kidney function at a mean follow-up of 12 months [4-18].

Conclusions

Laparoscopic NSS for kidney renal tumours seemed feasible and safe with no warm ischemia time. Further experience is needed to confirm this preliminary experience.

Background and Aims

The role of minimally invasive surgery (MIS) in nephrectomy for Wilms tumour (WT) is constantly evolving. Similarly, use of nephron sparing surgery (NSS) for unilateral tumours in non-syndromic children is increasingly advocated. The aim of this study was to identify factors limiting the use of laparoscopy in WT nephrectomy (LN) and NSS within our population.

Methods

A retrospective review of consecutive children who underwent nephrectomy for WT from January 2015 - January 2022 was undertaken. Those with bilateral WT or requiring cardiac input were excluded. Preoperative data were evaluated against the latest Children’s Cancer and Leukaemia Group Clinical Management Guidelines (CCLG/SIOP Umbrella Protocol – January 2020) for renal tumours, to assess feasibility of LN or NSS. Data are presented as median (IQR).

Results

Twenty-four children treated for WT met the inclusion criteria, ten were excluded by the above criteria. Median age at diagnosis was 33 months (23 - 67) and the median tumour volume prior to neoadjuvant chemotherapy was 471 ml (258 - 743). Three children (13%) would have been amenable to LN and underwent open nephrectomy. The most frequent contraindication to LN was infiltration of extrarenal structures or extension beyond the ipsilateral border of spinal column 11/21 (52%); 4/21 (19%) had >1 contraindication. NSS would have been suitable for 1/24 (4%); 18/23 (78%) had >1 contraindication for NSS, with the most frequently encountered limiting factor being tumour volume at diagnosis >300 ml, 17/23 (74%).

Conclusions

Retrospective comparison of a series of WT patients against current guidelines demonstrates that adoption of MIS and NSS in WT is limited in most children by advanced local stage at diagnosis. Identification of factors permitting earlier diagnosis and/or extension of the conservative, yet safe SIOP/CCLG appear necessary if less invasive surgical approaches in WT are to be more widely achieved in the UK.

Background and Aims

NSS for bilateral Wilms tumour (BWT) is the accepted standard. It is also desirable in unilateral syndromic cases (USD). NSS in cases of unilateral non syndromic disease (UNSD) is still not universally accepted due to concerns about upstaging. The aim of our study was to evaluate the attitude of UK oncology surgeons towards NSS in general.

Methods

A 15-question survey was distributed to all UK paediatric oncological surgeons.

Results

24 surgeons from 16 centres participated. 10/16 (62.5%) treat between 5-10 WT per year.

14/16 (87.5%) centres would perform NSS for bilateral disease and 13/16 (81.2%) for USD. However only 10/16, 62.5% said that they would perform NSS for UNSD. One centre would refer all cases of NSS to another centre. 81.2% had performed NSS for BWT, 56.2% for USD and 43.7% for UNSD in the last 5 years.

Only 9/21 (42.8%) of surgeons felt that all UNSD patients who met the “Umbrella” criteria for NSS should be offered NSS. 16/23 (69.5%) felt that parents should always be given the option of NSS where children met the “Umbrella” criteria. Most surgeons (20/24, 83.3%) considered the local MDT as the ideal forum for NSS decisions to be made. 11/24 (45.8%) felt it should be the surgeon’s choice while only 6/24 (25%) felt the decision should involve the National Renal Advisory Panel (NRAP).

37.5% of respondents felt that referral to the NRAP should be made for NSS in BWT and USD, and 50% for UNSD. Only 6/24 (25%) thought that NSS should be centralised. All surgeons not doing NSS for UNSD would be willing to change their practice.

Conclusions

NSS for unilateral non syndromic Wilms tumour has not been fully embraced in the UK. There is minimal support for the centralisation of NSS. It is important to gain consensus on this issue in the UK.

Background and Aims

Nephron-Sparing surgery (NSS) in patients with Wilms Tumor (WT) is a surgically challenging procedure used in highly selective cases only. Virtual resections can be used for preoperative planning of NSS to estimate the remnant renal volume (RRV) and to virtually mimic radical tumor resection. In this single-center validation study, virtual resection for NSS planning and the user experience were evaluated.

Methods

Virtual resection was performed in nine patients with WT cases by two pediatric surgeons and one pediatric urologist. Pre- and postoperative MRI scans were used for 3D visualization. The virtual RRV was acquired after performing virtual resection and a questionnaire was used to assess the ease of use. The actual RRV was derived from the postoperative 3D visualization and compared to the derived virtual RRV.

Results

Virtual resection resulted in virtual RRVs that matched nearly perfectly with the actual RRVs. The questionnaire showed that virtual resection appeared to be straightforward and was not considered to be difficult.

Conclusions

This study demonstrated the potential of virtual resection as a new planning tool to estimate the RRV after NSS in patients with WT. Future research should further evaluate the clinical relevance of virtual resection by relating it to surgical outcome in NSS.

Background and Aims

INTRODUCTION
Nearly 40% of relapses in Wilms tumor (WT) occur in children whose tumors
were classified as intermediate risk. It was hypothesized that the absolute
blastema volume after preoperative chemotherapy (ABVAPCT) could have
prognostic value on event-free (EFS) and overall survival (OS).
Objective:
Investigate relationship between ABVAPCT with EFS and OS in patients with
intermediate risk wilms tumor.

Methods

Methods:

Our study collected patients from 2010 to 2021 in Onco-Pediatric Depatment. The ABVAPCT was calculated using the formula of Umbrella protocol: length × depth × thickness × 0.523 × (1- % post chemotherapy necrotic fraction) × % fraction of blastema. Student test was used for qualitative variables and Pearson test for quantitative parameters. Survival curves were obtained by Kaplan-Meier and compared by log-rank test.

Results

Results: Our series consisted of 61 patients; 34 boys and 27 girls with a median age of 36 months (10-192 months). The histological type was stromal in 15 cases (24,6%), blastemal in one case (1,6%), epithelial in 2 cases (3,3%), regressive in 18 cases (29,9%) and mixte in 25 cases (41%).

There was not a significant relationship between the ABVAPCT and the histological types (p=0,077), laterality (p=0,094) and gender (p=0,052). Nevertheless, there was a significant association between EFS and the ABVAPCT in the absence of a threshold (p=0,001) or when the cutoff of 100ml was taken into consideration (p= 0,016). This was not the case of the ABVAPCT with the threshold of 20ml (p=0,633). There was not a significant difference in term of survival when a cut off 20ml or 100ml were considered. However, this was not the case between the total absence and the presence of the ABVAPCT (p=0,001).

Conclusions

Conclusions:

The ABVAPCT seems to be of prognostic relevance, showing that the total absence of the absolute blastemal volume have a better outcome and a better survival.