Surgical Management of Wilms Tumors with Intravenous Extension: A Multicenter Analysis of Clinical Management with Technical Insights.

BACKGROUND: About 5% of Wilms tumors present with vascular extension, which sometimes extends to the right atrium. Vascular extension does not affect the prognosis, but impacts the surgical strategy, which is complex and not fully standardized. Our goal is to identify elements of successful surgical management of Wilms tumors with vascular extensions. PATIENTS AND METHODS: A retrospective study of pediatric Wilms tumors treated at three sites (January 1999-June 2019) was conducted. The inclusion criterion was the presence of a renal vein and vena cava thrombus at diagnosis. Tumor stage, pre and postoperative treatment, preoperative imaging, operative report, pathology, operative complications, and follow-up data were reviewed. RESULTS: Of the 696 pediatric patients with Wilms tumors, 69 (9.9%) met the inclusion criterion. In total, 24 patients (37.5%) had a right atrial extension and two presented with Budd-Chiari syndrome at diagnosis. Two died at diagnosis owing to pulmonary embolism. All patients received neoadjuvant chemotherapy and thrombus regressed in 35.6% of cases. Overall, 14 patients had persistent intra-atrial thrombus extension (58%) and underwent cardiopulmonary bypass. Most thrombi (72%) were removed intact with nephrectomy. Massive intraoperative bleeding occurred during three procedures. Postoperative renal insufficiency was identified as a risk factor for patient survival (p = 0.01). With a median follow-up of 9 years (range: 0.5-20 years), overall survival was 89% and event-free survival was 78%. CONCLUSIONS: Neoadjuvant chemotherapy with proper surgical strategy resulted in a survival rate comparable to that of children with Wilms tumors without intravascular extension. Clinicians should be aware that postoperative renal insufficiency is associated with worse survival outcomes.

Neurological hospitalisations in childhood cancer survivors treated before 2001: findings from the French Childhood Cancer Survivor Study cohort.

PURPOSE: Childhood cancer survivors (CCS) have an increased risk of developing late chronic diseases, which can be influenced by the cancer type and its treatment. These chronic diseases can be severe and disabling, typically emerging years to decades after treatment. These deficits negatively impact quality of life, intelligence quotient, and memory. This study investigated how much the cancer type and treatment could affect the neurological hospitalisations in the French Childhood Cancer Survivors Study (FCCSS). METHODS: We included 5579 childhood cancer survivors (CCS), diagnosed with solid tumours or lymphoma between 1945 and 2000, treated before 2001 and below the age of 21 years at initial treatment. The follow-up period was from 2006 to 2018. Hospitalisation data were obtained by linkage with the National Health Data System. We calculated the relative hospitalisation rate (RHRs) and absolute excess rate (AERs). Multivariable analyses were conducted using a Generalized Linear Model (GLM) with a Poisson distribution to estimate the association between neurological hospitalisation and patient characteristics. The expected number of hospitalisations served as an offset to compare the risk for FCCSS survivors with that of the reference population. Risk estimates were reported as relative risk (RR) with 95% confidence intervals. RESULTS: The hospitalisation rate for CCS was 114.2 per 10,000 person-years (PY), compared to 48.4 in the reference population. The highest hospitalisation rates were observed for epilepsy (AER = 27.1 per 10000 PY, 95%CI: 23.5-31.2 and RHR = 5.1, 95%CI 4.4-5.7). In multivariable analyses, central nervous system (CNS) tumours survivors had the highest relative risk (RR) of hospitalisation (RR = 9.4, 95%CI: 6.7-13.1) followed by neuroblastoma survivors (RR = 2.5, 95%CI: 1.7-3.7). In the whole population, survivors who received radiation to the head and neck had a significantly higher risk of hospitalisation (RR = 3.9, 95%CI: 3.3-4.7) compared to those who did not receive radiotherapy. CONCLUSIONS: Head and neck irradiation was identified as a strong risk factor for hospitalisation. This underlines the importance of implementing specific neurologic surveillance programs for at-risk individuals.

Phase II study of 131 I-metaiodobenzylguanidine with 5 days of topotecan for refractory or relapsed neuroblastoma: Results of the French study MIITOP.

PURPOSE: We report the results of the French multicentric phase II study MIITOP (NCT00960739), which evaluated tandem infusions of 131 I-metaiodobenzylguanidine (mIBG) and topotecan in children with relapsed/refractory metastatic neuroblastoma (NBL). METHODS: Patients received 131 I-mIBG on day 1, with intravenous topotecan daily on days 1-5. A second activity of 131 I-mIBG was given on day 21 to deliver a whole-body radiation dose of 4 Gy, combined with a second course of topotecan on days 21-25. Peripheral blood stem cells were infused on day 31. RESULTS: Thirty patients were enrolled from November 2008 to June 2015. Median age at diagnosis was 5.5 years (2-20). Twenty-one had very high-risk NBL (VHR-NBL), that is, stage 4 NBL at diagnosis or at relapse, with insufficient response (i.e., less than a partial response of metastases and more than three mIBG spots) after induction chemotherapy; nine had progressive metastatic relapse. Median Curie score at inclusion was 6 (1-26). Median number of prior lines of treatment was 3 (1-7). Objective response rate was 13% (95% confidence interval [CI]: 4-31) for the whole population, 19% for VHR-NBL, and 0% for progressive relapses. Immediate tolerance was good, with nonhematologic toxicity limited to grade-2 nausea/vomiting in eight patients. Two-year event-free survival was 17% (95% CI: 6-32). Among the 16 patients with VHR-NBL who had not received prior myeloablative busulfan-melphalan consolidation, 13 had at least stable disease after MIITOP; 11 subsequently received busulfan-melphalan; four of them were alive (median follow-up: 7 years). CONCLUSION: MIITOP showed acceptable tolerability in this heavily pretreated population and encouraging survival rates in VHR-NBL when followed by busulfan-melphalan.

IL10RA modulates crizotinib sensitivity in NPM1-ALK+ anaplastic large cell lymphoma.

Anaplastic large cell lymphoma (ALCL) is a T-cell malignancy predominantly driven by a hyperactive anaplastic lymphoma kinase (ALK) fusion protein. ALK inhibitors, such as crizotinib, provide alternatives to standard chemotherapy with reduced toxicity and side effects. Children with lymphomas driven by nucleophosmin 1 (NPM1)-ALK fusion proteins achieved an objective response rate to ALK inhibition therapy of 54% to 90% in clinical trials; however, a subset of patients progressed within the first 3 months of treatment. The mechanism for the development of ALK inhibitor resistance is unknown. Through genome-wide clustered regularly interspaced short palindromic repeats (CRISPR) activation and knockout screens in ALCL cell lines, combined with RNA sequencing data derived from ALK inhibitor-relapsed patient tumors, we show that resistance to ALK inhibition by crizotinib in ALCL can be driven by aberrant upregulation of interleukin 10 receptor subunit alpha (IL10RA). Elevated IL10RA expression rewires the STAT3 signaling pathway, bypassing otherwise critical phosphorylation by NPM1-ALK. IL-10RA expression does not correlate with response to standard chemotherapy in pediatric patients, suggesting that a combination of crizotinib and chemotherapy could prevent ALK inhibitor resistance-specific relapse.

Clinical characteristics and outcomes of children with WAGR syndrome and Wilms tumor and/or nephroblastomatosis: The 30-year SIOP-RTSG experience.

BACKGROUND: WAGR syndrome (Wilms tumor, aniridia, genitourinary anomalies, and range of developmental delays) is a rare contiguous gene deletion syndrome with a 45% to 60% risk of developing Wilms tumor (WT). Currently, surveillance and treatment recommendations are based on limited evidence. METHODS: Clinical characteristics, treatments, and outcomes were analyzed for patients with WAGR and WT/nephroblastomatosis who were identified through International Society of Pediatric Oncology Renal Tumor Study Group (SIOP-RTSG) registries and the SIOP-RTSG network (1989-2019). Events were defined as relapse, metachronous tumors, or death. RESULTS: Forty-three patients were identified. The median age at WT/nephroblastomatosis diagnosis was 22 months (range, 6-44 months). The overall stage was available for 40 patients, including 15 (37.5%) with bilateral disease and none with metastatic disease. Histology was available for 42 patients; 6 nephroblastomatosis without further WT and 36 WT, including 19 stromal WT (52.8%), 12 mixed WT (33.3%), 1 regressive WT (2.8%) and 2 other/indeterminable WT (5.6%). Blastemal type WT occurred in 2 patients (5.6%) after prolonged treatment for nephroblastomatosis; anaplasia was not reported. Nephrogenic rests were present in 78.9%. Among patients with WT, the 5-year event-free survival rate was 84.3% (95% confidence interval, 72.4%-98.1%), and the overall survival rate was 91.2% (95% confidence interval, 82.1%-100%). Events (n = 6) did not include relapse, but contralateral tumor development (n = 3) occurred up to 7 years after the initial diagnosis, and 3 deaths were related to hepatotoxicity (n = 2) and obstructive ileus (n = 1). CONCLUSIONS: Patients with WAGR have a high rate of bilateral disease and no metastatic or anaplastic tumors. Although they can be treated according to existing WT protocols, intensive monitoring of toxicity and surveillance of the remaining kidney(s) are advised. LAY SUMMARY: WAGR syndrome (Wilms tumor, aniridia, genitourinary anomalies, and range of developmental delays) is a rare genetic condition with an increased risk of developing Wilms tumor. In this study, 43 patients with WAGR and Wilms tumor (or Wilms tumor precursor lesions/nephroblastomatosis) were identified through the international registry of the International Society of Pediatric Oncology Renal Tumor Study Group (SIOP-RTSG) and the SIOP-RTSG network. In many patients (37.5%), both kidneys were affected. Disease spread to other organs (metastases) did not occur. Overall, this study demonstrates that patients with WAGR syndrome and Wilms tumor can be treated according to existing protocols. However, intensive monitoring of treatment complications and surveillance of the remaining kidney(s) are advised.

Maternal and perinatal characteristics, congenital malformations and the risk of wilms tumor: the ESTELLE study.

PURPOSE: Wilms tumor (WT), or nephroblastoma, is an embryonic tumor that constitutes the most common renal tumor in children. Little is known about the etiology of WT. The aim of this study was to investigate whether maternal or perinatal characteristics were associated with the risk of WT. METHODS: The ESTELLE study is a national-based case-control study that included 117 cases of WT and 1,100 controls younger than 11 years old. The cases were children diagnosed in France in 2010-2011 and the controls were frequency matched with cases by age and gender. The mothers of case and control children responded to a telephone questionnaire addressing sociodemographic and perinatal characteristics, childhood environment, and lifestyle. Unconditional logistic regression models adjusted on potential cofounders were used to estimate the odds ratios (OR) and their confidence intervals (95% CI). RESULTS: High birth weight and the presence of congenital malformation were associated with WT (OR 1.9 [95% CI 1.0-3.7] and OR 2.5 [95% CI 1.1-5.8], respectively). No association with breastfeeding or folic acid supplementation was observed. CONCLUSIONS: Although potential recall bias cannot be excluded, our findings reinforce the hypothesis that high birth weight and the presence of congenital malformation may be associated with an increased risk of WT. Further investigations are needed to further elucidate the possible role of maternal characteristics in the etiology of WT.

Prognostic impact of postoperative 123I-metaiodobenzylguanidine scintigraphy: added value of SPECT/CT and semiquantification of the uptake at the surgical site.

BACKGROUND: The aim of this study was to assess the prognostic value of postoperative 123I-MIBG scintigraphy, including systematic SPECT/CT and semiquantification of the uptake at the surgical site, in a prospective series of NB patients. METHODS: Patients operated for neuroblastoma and who had benefited from postoperative 123I-MIBG scintigraphy were prospectively and consecutively included. Completeness of surgery was assessed on operative report. One month postoperative 123I-MIBG scintigraphy included planar acquisition and SPECT/CT. Semi-quantification of the 123I-MIBG SPECT/CT uptake at the surgical site was performed and ratios to reference (liver and mediastinum) areas were calculated. RESULTS: Thirty patients were included between August 2012 and July 2015. Median follow-up was 36 months (range 10-98). Surgery was considered as complete in 23 patients and incomplete in 7 patients. Eight patients (26.7%) presented progressive disease (1 progression and 7 recurrences). Seven patients died (23.3%), all from NB. Six (20%) patients had positive 123I-MIBG scintigraphy (3 on planar acquisitions and 6 on SPECT/CT) and 24 patients had negative 123I-MIBG scintigraphy. Five of the 6 patients (83%) with positive 123I-MIBG scintigraphy presented progressive disease. Ratio of the uptake at the surgical site to mediastinum was strongly and independently correlated with disease-free interval and overall survival (P=0.02 and 0.01 respectively). The amplified MYCN status was also confirmed as correlated with poorer outcomes. CONCLUSIONS: Postoperative 123I-MIBG scintigraphy including SPECT/CT and semiquantification of the uptake at the surgical site appeared to be a valuable prognostic tool in neuroblastoma.

Correction to: The pitfalls and promise of liquid biopsies for diagnosing and treating solid tumors in children: as review.

In the original version of this article, a reader pointed out that there was a mistake in the phrasing in a paragraph. This could potentially be harmful to children. The authors agree to change the wording. "vitreous fluid" will be changed to "aqueous humor".

The pitfalls and promise of liquid biopsies for diagnosing and treating solid tumors in children: a review.

Cell-free DNA profiling using patient blood is emerging as a non-invasive complementary technique for cancer genomic characterization. Since these liquid biopsies will soon be integrated into clinical trial protocols for pediatric cancer treatment, clinicians should be informed about potential applications and advantages but also weaknesses and potential pitfalls. Small retrospective studies comparing genetic alterations detected in liquid biopsies with tumor biopsies for pediatric solid tumor types are encouraging. Molecular detection of tumor markers in cell-free DNA could be used for earlier therapy response monitoring and residual disease detection as well as enabling detection of pathognomonic and therapeutically relevant genomic alterations.Conclusion: Existing analyses of liquid biopsies from children with solid tumors increasingly suggest a potential relevance for molecular diagnostics, prognostic assessment, and therapeutic decision-making. Gaps remain in the types of tumors studied and value of detection methods applied. Here we review the current stand of liquid biopsy studies for pediatric solid tumors with a dedicated focus on cell-free DNA analysis. There is legitimate hope that integrating fully validated liquid biopsy-based innovations into the standard of care will advance patient monitoring and personalized treatment of children battling solid cancers.What is Known:• Liquid biopsies are finding their way into routine oncological screening, diagnosis, and disease monitoring in adult cancer types fast.• The most widely adopted source for liquid biopsies is blood although other easily accessible body fluids, such as saliva, pleural effusions, urine, or cerebrospinal fluid (CSF) can also serve as sources for liquid biopsiesWhat is New:• Retrospective proof-of-concept studies in small cohorts illustrate that liquid biopsies in pediatric solid tumors yield tremendous potential to be used in diagnostics, for therapy response monitoring and in residual disease detection.• Liquid biopsy diagnostics could tackle some long-standing issues in the pediatric oncology field; they can enable accurate genetic diagnostics in previously unbiopsied tumor types like renal tumors or brain stem tumors leading to better treatment strategies.

From Wilms to kidney tumors: which ones require a biopsy?

Ninety percent of childhood renal tumors are Wilms tumors (nephroblastoma). While the Children's Oncology Group (COG) recommends primary surgery, the International Society of Paediatric Oncology (SIOP) recommends neoadjuvant chemotherapy, which can be initiated without histological confirmation if the presentation is typical for Wilms tumor. This review article describes the clinical, biological and radiologic criteria used by the SIOP community to consider diagnostic biopsy, i.e. when the renal origin is doubtful, when a pseudotumor is suspected or when a non-Wilms histology may be anticipated.

Parental smoking, maternal alcohol consumption during pregnancy and the risk of neuroblastoma in children. A pooled analysis of the ESCALE and ESTELLE French studies.

Neuroblastoma (NB) is the most common extra-cranial tumour in children. Little is known about the aetiology of NB. The early age at onset and the embryonic nature suggest a role for perinatal exposures. We conducted a pooled analysis of two French national population-based case-control studies to explore whether there was an association between parental smoking and alcohol consumption and the risk of NB. The mothers of 357 NB cases and 1,783 controls from general population, frequency matched by age and sex, were interviewed on demographic, socioeconomic and perinatal characteristics, maternal reproductive story, and life-style and childhood environment. Unconditional logistic regression was used to estimate pooled odds ratios and 95% confidence intervals. A meta-analysis of our findings with those of previous studies was also conducted. Maternal smoking during pregnancy was slightly more often reported for the cases (24.1%) than for the controls (19.7%) (OR 1.3 [95% CI 0.9-1.7]; summary OR from meta-analysis 1.1 [95% CI 1.0-1.3]. Paternal smoking in the year before child's birth were not associated with NB as independent exposure (OR 1.1 [95% CI 0.9-1.4] but the association was stronger when both parents reported having smoked during pregnancy (OR 1.5 [95% CI 1.1-2.1]. No association was observed with maternal alcohol intake during pregnancy (OR 1.0 [95% CI 0.8-1.4], summary OR from meta-analysis 1.0 [95% CI 0.9-1.2]. Our findings provide some evidence of an association between maternal smoking during pregnancy and NB and add another reason to recommend that women refrain from smoking during pregnancy.

Circulating tumor DNA analysis enables molecular characterization of pediatric renal tumors at diagnosis.

Circulating tumor DNA (ctDNA) is a powerful tool for the molecular characterization of cancer. The most frequent pediatric kidney tumors (KT) are Wilms' tumors (WT), but other diagnoses may occur. According to the SIOP strategy, in most countries pediatric KT have a presumptive diagnosis of WT if they are clinically and radiologically compatible. The histologic confirmation is established after post-chemotherapy nephrectomy. Thus, there is a risk for a small fraction of patients to receive neoadjuvant chemotherapy that is not adapted to the disease. The aim of this work is to perform molecular diagnosis of pediatric KT by tumor genetic characterization based on the analysis of ctDNA. We analyzed ctDNA extracted from plasma samples of 18 pediatric patients with KT by whole-exome sequencing and compared the results to their matched tumor and germline DNA. Copy number alterations (CNAs) and single nucleotide variations (SNVs) were analyzed. We were able to detect tumor cell specific genetic alterations-CNAs, SNVs or both-in ctDNA in all patients except in one (for whom the plasma sample was obtained long after nephrectomy). These results open the door to new applications for the study of ctDNA with regards to the molecular diagnosis of KT, with a possibility of its usefulness for adapting the treatment early after diagnosis, but also for disease monitoring and follow up.

Study of chromatin remodeling genes implicates SMARCA4 as a putative player in oncogenesis in neuroblastoma.

In neuroblastoma (NB), genetic alterations in chromatin remodeling (CRGs) and epigenetic modifier genes (EMGs) have been described. We sought to determine their frequency and clinical impact. Whole exome (WES)/whole genome sequencing (WGS) data and targeted sequencing (TSCA®) of exonic regions of 33 CRGs/EMGs were analyzed in tumor samples from 283 NB patients, with constitutional material available for 55 patients. The frequency of CRG/EMG variations in NB cases was then compared to the Genome Aggregation Database (gnomAD). The sequencing revealed SNVs/small InDels or focal CNAs of CRGs/EMGs in 20% (56/283) of all cases, occurring at a somatic level in 4 (7.2%), at a germline level in 12 (22%) cases, whereas for the remaining cases, only tumor material could be analyzed. The most frequently altered genes were ATRX (5%), SMARCA4 (2.5%), MLL3 (2.5%) and ARID1B (2.5%). Double events (SNVs/small InDels/CNAs associated with LOH) were observed in SMARCA4 (n = 3), ATRX (n = 1) and PBRM1 (n = 1). Among the 60 variations, 24 (8.4%) targeted domains of functional importance for chromatin remodeling or highly conserved domains but of unknown function. Variations in SMARCA4 and ATRX occurred more frequently in the NB as compared to the gnomAD control cohort (OR = 4.49, 95%CI: 1.63-9.97, p = 0.038; OR 3.44, 95%CI: 1.46-6.91, p = 0.043, respectively). Cases with CRG/EMG variations showed a poorer overall survival compared to cases without variations. Genetic variations of CRGs/EMGs with likely functional impact were observed in 8.4% (24/283) of NB. Our case-control approach suggests a role of SMARCA4 as a player of NB oncogenesis.

QuantumClone: clonal assessment of functional mutations in cancer based on a genotype-aware method for clonal reconstruction.

Motivation: In cancer, clonal evolution is assessed based on information coming from single nucleotide variants and copy number alterations. Nonetheless, existing methods often fail to accurately combine information from both sources to truthfully reconstruct clonal populations in a given tumor sample or in a set of tumor samples coming from the same patient. Moreover, previously published methods detect clones from a single set of variants. As a result, compromises have to be done between stringent variant filtering [reducing dispersion in variant allele frequency estimates (VAFs)] and using all biologically relevant variants. Results: We present a framework for defining cancer clones using most reliable variants of high depth of coverage and assigning functional mutations to the detected clones. The key element of our framework is QuantumClone, a method for variant clustering into clones based on VAFs, genotypes of corresponding regions and information about tumor purity. We validated QuantumClone and our framework on simulated data. We then applied our framework to whole genome sequencing data for 19 neuroblastoma trios each including constitutional, diagnosis and relapse samples. We confirmed an enrichment of damaging variants within such pathways as MAPK (mitogen-activated protein kinases), neuritogenesis, epithelial-mesenchymal transition, cell survival and DNA repair. Most pathways had more damaging variants in the expanding clones compared to shrinking ones, which can be explained by the increased total number of variants between these two populations. Functional mutational rate varied for ancestral clones and clones shrinking or expanding upon treatment, suggesting changes in clone selection mechanisms at different time points of tumor evolution. Availability and implementation: Source code and binaries of the QuantumClone R package are freely available for download at https://CRAN.R-project.org/package=QuantumClone. Contact: gudrun.schleiermacher@curie.fr or valentina.boeva@inserm.fr. Supplementary information: Supplementary data are available at Bioinformatics online.

The challenge of defining "ultra-high-risk" neuroblastoma.

Given the biological and clinical heterogeneity of neuroblastoma, risk stratification is vital to determining appropriate treatment. Historically, most patients with high-risk neuroblastoma (HR-NBL) have been treated uniformly without further stratification. Attempts have been made to identify factors that can be used to risk stratify these patients and to characterize an "ultra-high-risk" (UHR) subpopulation with particularly poor outcome. However, among published data, there is a lack of consensus in the definition of the UHR population and heterogeneity in the endpoints and statistical methods used. This review summarizes our current understanding of stratification of HR-NBL and discusses the complex issues in defining UHR neuroblastoma.

Enrollment in early-phase clinical trials in pediatric oncology: The experience at Institut Curie.

BACKGROUND: The European Paediatric Regulation was introduced in 2007 to facilitate access to new medicines for children. Our study explored accessibility of early-phase trials in pediatric oncology, in line with the European Paediatric Regulation, to identify the reasons for not inviting patients to participate, parents' refusal, or inclusion failure. PROCEDURE: We conducted a retrospective chart review at Institut Curie, Paris, for all pediatric patients whose cancer progressed despite known effective treatments between July 2010 and December 2013. RESULTS: Out of 100 patients in the palliative phase, 52 received one or more invitations to participate in early-phase trials. Twenty parents declined the invitation, mainly prioritizing quality of life or fearing constraints. Fourteen inclusions failed despite parental approval, mostly due to rapid clinical deterioration. Five patients received no invitations because no early-phase trials were available. Major reasons for noninclusion in the 43 remaining patients were presence of exclusion criteria or other physical factors, preference for conventional treatment, constraints, psychological factors, and follow-up in another hospital after moving. CONCLUSIONS: The Paediatric Regulation has led to increased availability of early-phase trials. Better timing of the proposal, designing less constraining early-phase trials, reducing waiting lists, and improving information for parents and children would facilitate pediatric access to new medicines.

Risk stratification of high-risk metastatic neuroblastoma: A report from the HR-NBL-1/SIOPEN study.

BACKGROUND: Risk stratification is crucial to treatment decision-making in neuroblastoma. This study aimed to explore factors present at diagnosis affecting outcome in patients aged ≥18 months with metastatic neuroblastoma and to develop a simple risk score for prognostication. PROCEDURE: Data were derived from the European high-risk neuroblastoma 1 (HR-NBL1)/International Society for Paediatric Oncology European Neuroblastoma (SIOPEN) trial with analysis restricted to patients aged ≥18 months with metastatic disease and treated prior to the introduction of immunotherapy. Primary endpoint was 5-year event-free survival (EFS). Prognostic factors assessed were sex, age, tumour MYCN amplification (MNA) status, serum lactate dehydrogenase (LDH)/ferritin, primary tumour and metastatic sites. Factors significant in univariate analysis were incorporated into a multi-variable model and an additive scoring system developed based on estimated log-cumulative hazard ratios. RESULTS: The cohort included 1053 patients with median follow-up 5.5 years and EFS 27 ± 1%. In univariate analyses, age; serum LDH and ferritin; involvement of bone marrow, bone, liver or lung; and >1 metastatic system/compartment were associated with worse EFS. Tumour MNA was not associated with worse EFS. A multi-variable model and risk score incorporating age (>5 years, 2 points), serum LDH (>1250 U/L, 1 point) and number of metastatic systems (>1, 2 points) were developed. EFS was significantly correlated with risk score: EFS 52 ± 9% for score = 0 versus 6 ± 3% for score = 5 (P < 0.0001). CONCLUSIONS: A simple score can identify an "ultra-high risk" (UHR) cohort (score = 5) comprising 8% of patients with 5-year EFS <10%. These patients appear not to benefit from induction therapy and could potentially be directed earlier to alternative experimental therapies in future trials.