Biological sample collection to advance research and treatment: a Fight Osteosarcoma Through European Research (FOSTER) and Euro Ewing Consortium (EEC) statement.

Osteosarcoma and Ewing sarcoma are bone tumours mostly diagnosed in children, adolescents and young adults. Despite multi-modal therapy, morbidity is high and survival rates remain low, especially in the metastatic disease setting. Trials investigating targeted therapies and immunotherapies have not been ground-breaking. Better understanding of biological subgroups, the role of the tumour immune microenvironment, factors that promote metastasis and clinical biomarkers of prognosis and drug response are required to make progress. A prerequisite to achieve desired success is a thorough, systematic and clinically linked biological analysis of patient samples but disease rarity and tissue processing challenges such as logistics and infrastructure have contributed to a lack of relevant samples for clinical care and research. There is a need for a Europe-wide framework to be implemented for the adequate and minimal sampling, processing, storage and analysis of patient samples. Two international panels of scientists, clinicians and patient and parent advocates have formed the Fight Osteosarcoma Through European Research (FOSTER) consortium and the Euro Ewing Consortium (EEC). The consortia shared their expertise and institutional practices to formulate new guidelines. We report new reference standards for adequate and minimally required sampling (time points, diagnostic samples, liquid biopsy tubes), handling and biobanking to enable advanced biological studies in bone sarcoma. We describe standards for analysis and annotation to drive collaboration and data harmonisation with practical, legal and ethical considerations. This position paper provides comprehensive guidelines that should become the new standards of care that will accelerate scientific progress, promote collaboration and improve outcomes.

Efficacy and safety of larotrectinib in TRK fusion-positive primary central nervous system tumors.

BACKGROUND: Larotrectinib is a first-in-class, highly selective tropomyosin receptor kinase (TRK) inhibitor approved to treat adult and pediatric patients with TRK fusion-positive cancer. The aim of this study was to evaluate the efficacy and safety of larotrectinib in patients with TRK fusion-positive primary central nervous system (CNS) tumors. METHODS: Patients with TRK fusion-positive primary CNS tumors from two clinical trials (NCT02637687, NCT02576431) were identified. The primary endpoint was investigator-assessed objective response rate (ORR). RESULTS: As of July 2020, 33 patients with TRK fusion-positive CNS tumors were identified (median age: 8.9 years; range: 1.3-79.0). The most common histologies were high-grade glioma (HGG; n = 19) and low-grade glioma (LGG; n = 8). ORR was 30% (95% confidence interval [CI]: 16-49) for all patients. The 24-week disease control rate was 73% (95% CI: 54-87). Twenty-three of 28 patients (82%) with measurable disease had tumor shrinkage. The 12-month rates for duration of response, progression-free survival, and overall survival were 75% (95% CI: 45-100), 56% (95% CI: 38-74), and 85% (95% CI: 71-99), respectively. Median time to response was 1.9 months (range 1.0-3.8 months). Duration of treatment ranged from 1.2-31.3+ months. Treatment-related adverse events were reported for 20 patients, with grade 3-4 in 3 patients. No new safety signals were identified. CONCLUSIONS: In patients with TRK fusion-positive CNS tumors, larotrectinib demonstrated rapid and durable responses, high disease control rate, and a favorable safety profile.

Endoscopic extended transsphenoidal surgery for newly diagnosed paediatric craniopharyngiomas.

PURPOSE: Endoscopic extended transsphenoidal surgery (EETSS) has gained popularity for treatment of craniopharyngiomas. The aim of this study is to assess the outcome of endoscopic extended transsphenoidal surgery (EETSS) for newly diagnosed paediatric craniopharyngiomas. METHODS: Patient details were obtained from a prospective database of all endoscopic transnasal operations performed by a single surgeon. Outcomes including visual function, pituitary function, body mass index (BMI), postoperative neurological deficit, extent of resection and recurrence on follow-up were obtained. Obesity was defined as BMI percentile of equal to or greater than 95%. RESULTS: Between January 2011 and January 2020, 15 of 16 children (5-18 years old) with newly diagnosed craniopharyngiomas underwent EETSS. Four patients had a conchal-type sphenoid sinus. Gross total resection (GTR) was achieved in 4 patients and near total resection (NTR) in 5 patients. The remaining 6 had subtotal resection (STR). Postoperative radiotherapy was used in 6 patients (4 with STR, 2 with NTR). There were no postoperative deaths, strokes or CSF leaks. Normalisation of visual fields (VF) occurred in 9/13 patients with preoperative VF defects. One patient developed a new visual field defect. During a median follow-up period of 74 (8-104) months, 2 patients have required further surgery for tumour progression following initial STR, where a tumour remnant was left in situ to preserve the pituitary stalk. 6/11 patients developed new anterior pituitary dysfunction as a result of surgery and 9/12 developed new diabetes insipidus (DI). At the time of last follow-up, 14/15 children had anterior panhypopituitarism, 13/15 had DI and 1 patient developed new onset obesity. Two patients, who were obese preoperatively, were no longer obese at last follow-up. CONCLUSIONS: EETSS can be performed as the first option in the majority of children with newly diagnosed craniopharyngioma, despite factors such as small nose, non-pneumatised sphenoid sinus, small sella or purely suprasellar tumour location. Preservation of the pituitary stalk at the expense of leaving residual tumour may not be in the best interests of the patient.

Survival of childhood and adolescent/young adult (AYA) cancer patients in Ireland during 1994-2013: comparisons by age.

BACKGROUND: Some studies indicate that survival of adolescents and young adults (AYA) with cancer may be inferior to that of younger children with similar cancers, possibly related (in part) to differences in access to centralized or standardized treatment. AIMS: This study aims to evaluate differences in survival for AYA patients when compared with paediatric patients treated in Ireland over a 20-year time period. METHODS: This study compares relative survival for patients diagnosed in Ireland at ages 0-15 (paediatric group) and 16-24 (AYA group) during 1994-2013, followed to the end of 2014, for cancers defined by the International Classification of Childhood Cancer (ICCC) (Third Edition) group or subgroup. Five-year relative survival estimates, and excess hazard ratios (EHR) comparing excess mortality associated with a cancer diagnosis among AYA with that in the paediatric group, are presented. This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors. RESULTS: Significantly higher excess mortality was found for AYA with leukaemias, lymphomas, astrocytomas, malignant bone tumours, and Ewing and related bone sarcomas, soft tissue sarcomas and 'other/unspecified' epithelial cancers, rhabdomyosarcomas, and 'other and unspecified' carcinomas. In contrast, lower excess mortality was found in the AYA group for all cancers and intracranial/intraspinal tumours, and for gliomas other than astrocytomas or ependymomas. Comparing 1994-2003 and 2004-2013 cohorts, age-related survival differences narrowed for lymphoid leukaemias, but widened for all cancers combined and intracranial/intraspinal tumours combined. Centralization of services varied depending upon cancer subtype, with leukaemias, CNS tumours and bone sarcomas most centralized. Within these, improvements in survival for leukaemias and CNS tumours have been seen for the AYA population. CONCLUSIONS: Reasons for age-related survival differences, and differences in time-trend by age group, are not clear. The significant narrowing of survival differences by age in more recent years for lymphoid leukaemias reflects a more marked recent increase in survival among AYA. More work is required to explain and improve other age-related survival differences.

Paediatric malignant melanoma in Ireland: A population study and review of the literature.

INTRODUCTION: Malignant melanoma is increasing in frequency worldwide; however, this disease is rare in children. As large-scale studies on paediatric melanoma are lacking, management is currently often based upon the understanding of the disease process in adults. The aim of this study was to characterise cases of paediatric melanoma diagnosed in the Republic of Ireland over a 21-year period. METHODS: This was a retrospective, multicentre study using national data provided by the National Cancer Registry of Ireland and individual practitioners. RESULTS: Twenty-four cases of melanoma treated in 11 different centres were included in the study. The median patient age at diagnosis was 15 years. The majority of cases arose on the limbs. The median Breslow thickness in patients of the pre-pubertal age group was 8.25 mm, while in children more than 13 years, it was 1.65 mm. Eight patients had disease recurrence and five patients died. CONCLUSION: The diagnosis of melanoma remains rare in children. This study contributes to our current understanding of malignant melanoma in paediatric patients; however, further investigation of the disease characteristics in this group is necessary to achieve optimal management of these cases and therefore improve outcomes.

Survival and prognosis with osteosarcoma: outcomes in more than 2000 patients in the EURAMOS-1 (European and American Osteosarcoma Study) cohort.

BACKGROUND: High-grade osteosarcoma is a primary malignant bone tumour mainly affecting children and young adults. The European and American Osteosarcoma Study (EURAMOS)-1 is a collaboration of four study groups aiming to improve outcomes of this rare disease by facilitating randomised controlled trials. METHODS: Patients eligible for EURAMOS-1 were aged ≤40 years with M0 or M1 skeletal high-grade osteosarcoma in which case complete surgical resection at all sites was deemed to be possible. A three-drug combination with methotrexate, doxorubicin and cisplatin was defined as standard chemotherapy, and between April 2005 and June 2011, 2260 patients were registered. We report survival outcomes and prognostic factors in the full cohort of registered patients. RESULTS: For all registered patients at a median follow-up of 54 months (interquartile range: 38-73) from biopsy, 3-year and 5-year event-free survival were 59% (95% confidence interval [CI]: 57-61%) and 54% (95% CI: 52-56%), respectively. Multivariate analyses showed that the most adverse factors at diagnosis were pulmonary metastases (hazard ratio [HR] = 2.34, 95% CI: 1.95-2.81), non-pulmonary metastases (HR = 1.94, 95% CI: 1.38-2.73) or an axial skeleton tumour site (HR = 1.53, 95% CI: 1.10-2.13). The histological subtypes telangiectatic (HR = 0.52, 95% CI: 0.33-0.80) and unspecified conventional (HR = 0.67, 95% CI: 0.52-0.88) were associated with a favourable prognosis compared with chondroblastic subtype. The 3-year and 5-year overall survival from biopsy were 79% (95% CI: 77-81%) and 71% (95% CI: 68-73%), respectively. For patients with localised disease at presentation and in complete remission after surgery, having a poor histological response was associated with worse outcome after surgery (HR = 2.13, 95% CI: 1.76-2.58). In radically operated patients, there was no good evidence that axial tumour site was associated with worse outcome. CONCLUSIONS: In conclusion, data from >2000 patients registered to EURAMOS-1 demonstrated survival rates in concordance with institution- or group-level osteosarcoma trials. Further efforts are required to drive improvements for patients who can be identified to be at higher risk of adverse outcome. This trial reaffirms known prognostic factors, and owing to the large numbers of patients registered, it sheds light on some additional factors to consider.

Scurvy: an unusual complication of paediatric cancer treatment.

Scurvy is a disease that is rarely encountered in modern medicine. A condition that was classically associated with sailors, its incidence has decreased dramatically since the discovery of its association with vitamin C deficiency. We present the case of a 2-year-old boy, whose treatment for neuroblastoma was complicated by gastrointestinal disease, which necessitated enteral feeding. While still undergoing treatment, he started to complain about increasing pain in his lower limbs, which appeared to be markedly tender on palpation. Radiographic findings suggested a diagnosis of scurvy, which was subsequently confirmed on serum biochemistry. This was an unexpected finding, as the child had been receiving adequate vitamin C in his enteral feeds. However, his absorption had become severely impaired due to pseudomembranous gastritis and enteritis, leading to his deficient state. He significantly improved after intravenous ascorbic acid replacement and demonstrated a full recovery, both clinically and radiologically. This case highlights the importance of considering scurvy in the differential diagnosis for at-risk patients. Early recognition can facilitate the simple treatment of this potentially serious condition.

Revised antiemetics guidelines and the impact on nutritional status during induction chemotherapy in children with high-risk neuroblastoma.

BACKGROUND: High-risk neuroblastoma (HR NBL) treatment requires intensive induction chemotherapy. The profoundly emetogenic agents used can compromise nutritional status. Our institution introduced a new antiemetic guideline in 2010 incorporating regular dexamethasone, in addition to ondansetron, for all highly emetogenic protocols. PROCEDURE: A retrospective comparative review of pediatric patients diagnosed with HR NBL who received rapid COJEC induction chemotherapy as per HR-SIOPEN NBL trial. Prophylactic antiemetics were prescribed regardless of chemotherapy emetogenicity in group A (2004-2010) but for defined time periods considering chemotherapy emetogenicity in group B (2010-2017). RESULTS: Sixty-three children were eligible for inclusion (median age, 31 months; range, 1-88 months). Group A had more episodes of emesis than group B (189 vs. 116, P < 0.0001). There was a significant difference in weight-for-age Z score change between the groups by induction end (P = 0.0027). Four children (13%) in group A lost >10% body weight versus none in group B. Nutrition support (NS) was utilized by 29 children (94%) in group A and 22 children (69%) in group B. Group A had a median of 3 (range, 1-7) admissions for febrile neutropenia (FN) versus a median of 1.5 (range, 0-4) for group B (P = 0.003) during induction. CONCLUSION: The review of our guidelines led to reduced emesis frequency for group B. They also required less NS, followed expected growth trajectories more closely and had fewer FN admissions. We propose that this may have occurred due to better emesis control resulting in improved nutritional status and associated enhanced immune function.

Sodium Thiosulfate for Protection from Cisplatin-Induced Hearing Loss.

BACKGROUND: Cisplatin chemotherapy and surgery are effective treatments for children with standard-risk hepatoblastoma but may cause considerable and irreversible hearing loss. This trial compared cisplatin with cisplatin plus delayed administration of sodium thiosulfate, aiming to reduce the incidence and severity of cisplatin-related ototoxic effects without jeopardizing overall and event-free survival. METHODS: We randomly assigned children older than 1 month and younger than 18 years of age who had standard-risk hepatoblastoma (≤3 involved liver sectors, no metastatic disease, and an alpha-fetoprotein level of >100 ng per milliliter) to receive cisplatin alone (at a dose of 80 mg per square meter of body-surface area, administered over a period of 6 hours) or cisplatin plus sodium thiosulfate (at a dose of 20 g per square meter, administered intravenously over a 15-minute period, 6 hours after the discontinuation of cisplatin) for four preoperative and two postoperative courses. The primary end point was the absolute hearing threshold, as measured by pure-tone audiometry, at a minimum age of 3.5 years. Hearing loss was assessed according to the Brock grade (on a scale from 0 to 4, with higher grades indicating greater hearing loss). The main secondary end points were overall survival and event-free survival at 3 years. RESULTS: A total of 109 children were randomly assigned to receive cisplatin plus sodium thiosulfate (57 children) or cisplatin alone (52) and could be evaluated. Sodium thiosulfate was associated with few high-grade toxic effects. The absolute hearing threshold was assessed in 101 children. Hearing loss of grade 1 or higher occurred in 18 of 55 children (33%) in the cisplatin-sodium thiosulfate group, as compared with 29 of 46 (63%) in the cisplatin-alone group, indicating a 48% lower incidence of hearing loss in the cisplatin-sodium thiosulfate group (relative risk, 0.52; 95% confidence interval [CI], 0.33 to 0.81; P=0.002). At a median of 52 months of follow-up, the 3-year rates of event-free survival were 82% (95% CI, 69 to 90) in the cisplatin-sodium thiosulfate group and 79% (95% CI, 65 to 88) in the cisplatin-alone group, and the 3-year rates of overall survival were 98% (95% CI, 88 to 100) and 92% (95% CI, 81 to 97), respectively. CONCLUSIONS: The addition of sodium thiosulfate, administered 6 hours after cisplatin chemotherapy, resulted in a lower incidence of cisplatin-induced hearing loss among children with standard-risk hepatoblastoma, without jeopardizing overall or event-free survival. (Funded by Cancer Research UK and others; SIOPEL 6 ClinicalTrials.gov number, NCT00652132 ; EudraCT number, 2007-002402-21 .).

Intracystic interferon-alpha in pediatric craniopharyngioma patients: an international multicenter assessment on behalf of SIOPE and ISPN.

BACKGROUND: Craniopharyngiomas are frequent hypothalamo-pituitary tumors in children, presenting predominantly as cystic lesions. Morbidity from conventional treatment has focused attention on intracystic drug delivery, hypothesized to cause fewer clinical consequences. However, the efficacy of intracystic therapy remains unclear. We report the retrospective experiences of several global centers using intracystic interferon-alpha. METHODS: European Société Internationale d'Oncologie Pédiatrique and International Society for Pediatric Neurosurgery centers were contacted to submit a datasheet capturing pediatric patients with cystic craniopharyngiomas who had received intracystic interferon-alpha. Patient demographics, administration schedules, adverse events, and outcomes were obtained. Progression was clinical or radiological (cyst reaccumulation, novel cysts, or solid growth). RESULTS: Fifty-six children (median age, 6.3 y) from 21 international centers were identified. Median follow-up from diagnosis was 5.1 years (0.3-17.7 y). Lesions were cystic (n = 22; 39%) or cystic/solid (n = 34; 61%). Previous progression was treated in 43 (77%) patients before interferon use. In such cases, further progression was delayed by intracystic interferon compared with the preceding therapy for cystic lesions (P = 0.0005). Few significant attributable side effects were reported. Progression post interferon occurred in 42 patients (median 14 mo; 0-8 y), while the estimated median time to definitive therapy post interferon was 5.8 (1.8-9.7) years. CONCLUSIONS: Intracystic interferon-alpha can delay disease progression and potentially offer a protracted time to definitive surgery or radiotherapy in pediatric cystic craniopharyngioma, yet demonstrates a favorable toxicity profile compared with other therapeutic modalities-important factors for this developing age group. A prospective, randomized international clinical trial assessment is warranted.

One to Watch: A Germ Cell Tumor Arising in an Undescended Testicle in Rubinstein-Taybi Syndrome.

A male preterm infant was born with dysmorphic features consistent with Rubinstein-Taybi syndrome (RTS). An undescended right testicle was noted on examination. At 5 months of age he developed a palpable right-sided abdominal mass and an elevated alpha-fetoprotein. Histology revealed a malignant germ cell neoplasm arising within the undescended testis. This is the first reported case of a germ cell tumor occurring in a pediatric patient with RTS. Urologic abnormalities occur in approximately 52% of RTS patients, of which cryptorchidism is the commonest. Given the frequency of undescended testes in this population, closer screening may be warranted.

Mutations in the transcriptional repressor REST predispose to Wilms tumor.

Wilms tumor is the most common childhood renal cancer. To identify mutations that predispose to Wilms tumor, we are conducting exome sequencing studies. Here we describe 11 different inactivating mutations in the REST gene (encoding RE1-silencing transcription factor) in four familial Wilms tumor pedigrees and nine non-familial cases. Notably, no similar mutations were identified in the ICR1000 control series (13/558 versus 0/993; P < 0.0001) or in the ExAC series (13/558 versus 0/61,312; P < 0.0001). We identified a second mutational event in two tumors, suggesting that REST may act as a tumor-suppressor gene in Wilms tumor pathogenesis. REST is a zinc-finger transcription factor that functions in cellular differentiation and embryonic development. Notably, ten of 11 mutations clustered within the portion of REST encoding the DNA-binding domain, and functional analyses showed that these mutations compromise REST transcriptional repression. These data establish REST as a Wilms tumor predisposition gene accounting for ∼2% of Wilms tumor.

Rhabdoid tumor: the Irish experience 1986-2013.

Nomenclature for the three recognized forms of rhabdoid tumor reflect their anatomic localization and include malignant rhabdoid tumor of the kidney (MRTK), extrarenal extracranial rhabdoid tumor (EERT), and atypical teratoid rhabdoid tumor (ATRT) involving the central nervous system. A strikingly simple karyotype belies the fact that rhabdoid tumors are among the most lethal human cancers, and now early strides are beginning to elucidate their molecular pathogenesis. Rhabdoid tumors are largely confined to the pediatric population, where they occur preferentially during infancy. Given the rarity of this tumor, international consensus on best treatment has only recently been achieved in conjunction with the establishment of the European Rhabdoid Tumor Registry. Between 1986 and 2013, 25 pediatric patients were diagnosed with rhabdoid tumor in the Republic of Ireland. Of these patients, 13 presented with ATRT, eight had MRTK, and four had EERT. The mean age at diagnosis was 38.8 months, with an equal sex incidence. Because of the lack of a standardized treatment strategy for rhabdoid tumors, these patients have been treated largely according to anatomic site, based on sarcoma, renal, or brain tumor protocols contemporary to their diagnoses. Of the patients, 84% received chemotherapy, 80% underwent surgery, and 44% had radiation therapy. The outcome overall was poor, independent of anatomic location. The overall survival rate was 24%, and mean time to death was just under 9 months.

Paediatric spinal glioblastoma: case report and review of therapeutic strategies.

INTRODUCTION: Although uncommon, there is significant morbidity and mortality associated with paediatric spinal glioblastoma. The paucity of cases makes treatment options difficult. The current recommended standard of care is biopsy followed by adjuvant chemo-radiotherapy, with emerging data supporting the role of safe gross total resection. OBJECTIVE: The purpose of this paper is to provide a single-institution case study and to discuss current and future therapeutic treatment strategies. CASE PRESENTATION: A 14-year-old boy presented with a 2-year history of intermittent back pain with recent progressively worsening motor and sensory deficits of the right side. Pre-operative MRI revealed an enhancing intra-medullary tumour extending from C2 to C7. During the operative case, no tumour-cord margin could be identified, and the patient underwent a subtotal excision. Histopathology confirmed glioblastoma. In the subsequent weeks, the patient's clinical condition deteriorated. Adjuvant therapy was declined by the family, and the patient died 9 weeks after initial presentation. CONCLUSION: Despite major advances in surgical techniques, peri-operative neuro-imaging as well as chemo-radiotherapy, the prognosis of a paediatric intra-medullary high-grade spinal tumour remains poor. Detailed analysis of our understanding of tumour dynamics in this patient group is important in establishing future therapeutic strategies.

Congenital sacrococcygeal PNET and chemotherapy.

We present the case of a congenital localised sacrococcygeal primitive neuroectodermal tumor treated aggressively with surgical resection and modified age-appropriate adjuvant chemotherapy. The conventional combination chemotherapy of vincristine, adriamycin, cyclophosphamide, ifosfamide and etoposide was modified to a regimen including vincristine, adriamicin, cyclophosphamide and actinomycin in order to minimise the predicted toxicity in this age group. Adjuvant "induction" chemotherapy commenced at 4 weeks of age and consisted of four cycles of vincristine, adriamycin and cyclophosphamide at 50%, 75%, 75% and 100% of recommended doses (vincristine 0.05 mg/kg, adriamycin 0.83 mg/kg daily × 2, cyclophosphamide 40 mg/kg) at 3-weekly intervals. This was followed by four cycles of "maintenance" chemotherapy with vincristine (0.025 mg/kg), actinomycin (0.025 mg/kg) and cyclophosphamide (36 mg/kg) at full recommended doses. Cardioxane at a dose of 16.6 mg/kg was infused immediately prior to the adriamycin. Our patient is thriving at 19 months out from end of treatment.

An audit of chemotherapy-induced nausea and vomiting in children.

An audit was conducted of the management of chemotherapy-induced nausea and vomiting in children and young people in the national Irish paediatric cancer unit. Over three months, the anti-emetic medication and the incidence of nausea and vomiting in 50 consecutive patient episodes were recorded among 25 children receiving chemotherapy for diverse malignancies. Anti-emetic prescription was found to be unrelated to the emetogenic potential of the chemotherapy received, so that effectiveness varied. Dexamethasone was used in only one case. Twenty children did not take any anti-emetics following discharge, although 11 experienced delayed vomiting, evidence-based guidelines were established and now include anti-emetic prescription that is proportional to the emetogenic potential of the chemotherapeutic regimen. It is also recommended that staff, patients, families and carers should receive education about the need for prescription and use of anti-emetics after discharge.

Prognostic stratification for children with hepatoblastoma: the SIOPEL experience.

PURPOSE: To identify factors relevant to long-term outcome in newly diagnosed hepatoblastoma, and define subgroups for clinical research on tailoring treatment to the individual patient. PATIENTS AND METHODS: Between 1995 and 2006 the SIOPEL group conducted two clinical trials which established risk-adapted therapy for hepatoblastoma patients. Patients were stratified into high-risk (AFP < 100 ng/mL and/or PRETEXT IV and/or vascular invasion and/or extra-hepatic intra-abdominal disease (V+/P+/E+) and/or metastases) and standard-risk (all others). The hierarchy of these factors plus multifocality, PRETEXT III, AFP > 1,200,000 ng/mL, patient age, platelet count and histology were further explored. The outcome measure was event-free survival (EFS). RESULTS: In 541 patients, reduced EFS correlated significantly with AFP < 100 ng/ml (hazard ratio [HR] 4.09, 95% confidence interval 2.16-7.75), AFP ≥ 1.2 × 10(6)ng/mL (2.48, 1.47-4.17), metastatic disease (3.02, 2.05-4.44), PRETEXT IV (2.15, 1.19-3.87), multifocality (1.59, 1.01-2.50), age > 5 years (2.76, 1.68-4.53); borderline with small cell undifferentiated (SCU) histology (2.29, 95% confidence interval 0.91-5.77); but not with PRETEXT III, age 30-60 months, platelet count or V+/P+/E+. By using the significant factors and SCU to stratify the population, we have identified three distinct prognostic groups: PRETEXT I/II/III, and no other factors, have 3 year EFS of 90%, PRETEXT IV and/or multifocal tumour and/or age> 5 years and/or AFP > 1.2 × 10(6) have 3 year EFS of 71% and SCU and/or AFP < 100 ng/mL and/or metastatic have a 3year EFS of 49%. CONCLUSION: Prognostic stratification for clinical research on newly diagnosed hepatoblastoma should take into consideration PRETEXT, metastatic disease, AFP, multifocality, age and SCU histology.