Adolescent- and adult-onset neuroblastic tumor: A retrospective multicenter observational study of patients diagnosed in France between 2000 and 2020.

BACKGROUND: Adult- and adolescent-onset neuroblastomas are rare, with no established therapy. In addition, rare pheochromocytomas may harbor neuroblastic components. This study was designed to collect epidemiological, diagnostic and therapeutic data in order to better define the characteristics of malignant peripheral neuroblastic tumors (MPNT) and composite pheochromocytomas (CP) with MPNT. PROCEDURE: Fifty-nine adults and adolescents (aged over 15 years) diagnosed with a peripheral or composite neuroblastic tumor, who were treated in one of 17 institutions between 2000 and 2020, were retrospectively studied. RESULTS: Eighteen patients with neuroblastoma (NB) or ganglioneuroblastoma (GNB) had locoregional disease, and 28 patients had metastatic stage 4 NB. Among the 13 patients with CP, 12 had locoregional disease. Fifty-eight percent of the population were adolescents and young adults under 24 years of age. The probability of 5-year event-free survival (EFS) was 40% (confidence interval: 27%-53%). CONCLUSIONS: Outcomes were better for patients with localized tumor than for patients with metastases. For patients with localized tumor, in terms of survival, surgical treatment was the best therapeutic option. Multimodal treatment with chemotherapy, surgery, radiotherapy, and immunotherapy-based maintenance allowed long-term survival for some patients. Adolescent- and adult-onset neuroblastoma appeared to have specific characteristics associated with poorer outcomes compared to pediatric neuroblastoma. Nevertheless, complete disease control improved survival. The presence of a neuroblastic component in pheochromocytoma should be considered when making therapeutic management decisions. The development of specific tools/resources (Tumor Referral Board, Registry, biology, and trials with new agents or strategies) may help to improve outcomes for patients.

Single-cell multiomics reveals the interplay of clonal evolution and cellular plasticity in hepatoblastoma.

Hepatoblastomas (HB) display heterogeneous cellular phenotypes that influence the clinical outcome, but the underlying mechanisms are poorly understood. Here, we use a single-cell multiomic strategy to unravel the molecular determinants of this plasticity. We identify a continuum of HB cell states between hepatocytic (scH), liver progenitor (scLP) and mesenchymal (scM) differentiation poles, with an intermediate scH/LP population bordering scLP and scH areas in spatial transcriptomics. Chromatin accessibility landscapes reveal the gene regulatory networks of each differentiation pole, and the sequence of transcription factor activations underlying cell state transitions. Single-cell mapping of somatic alterations reveals the clonal architecture of each tumor, showing that each genetic subclone displays its own range of cellular plasticity across differentiation states. The most scLP subclones, overexpressing stem cell and DNA repair genes, proliferate faster after neo-adjuvant chemotherapy. These results highlight how the interplay of clonal evolution and epigenetic plasticity shapes the potential of HB subclones to respond to chemotherapy.

Mutational signature, cancer driver genes mutations and transcriptomic subgroups predict hepatoblastoma survival.

BACKGROUND: Hepatoblastoma is the most frequent pediatric liver cancer. The current treatments lead to 80% of survival rate at 5 years. In this study, we evaluated the clinical relevance of molecular features to identify patients at risk of chemoresistance, relapse and death of disease. METHODS: All the clinical data of 86 children with hepatoblastoma were retrospectively collected. Pathological slides were reviewed, tumor DNA sequencing (by whole exome, whole genome or target) and transcriptomic profiling with RNAseq or 300-genes panel were performed. Associations between the clinical, pathological, mutational and transcriptomic data were investigated. RESULTS: High-risk patients represented 44% of our series and the median age at diagnosis was 21.9 months (range: 0-208). Alterations of the WNT/ß-catenin pathway and of the 11p15.5 imprinted locus were identified in 98% and 74% of the tumors, respectively. Other cancer driver genes mutations were only found in less than 11% of tumors. After neoadjuvant chemotherapy, disease-specific survival and poor response to neoadjuvant chemotherapy were associated with 'Liver Progenitor' (p = 0.00049, p < 0.0001) and 'Immune Cold' (p = 0.0011, p < 0.0001) transcriptomic tumor subtypes, SBS35 cisplatin mutational signature (p = 0.018, p = 0.001), mutations in rare cancer driver genes (p = 0.0039, p = 0.0017) and embryonal predominant histological type (p = 0.0013, p = 0.0077), respectively. Integration of the clinical and molecular features revealed a cluster of molecular markers associated with resistance to chemotherapy and survival, enlightening transcriptomic 'Immune Cold' and Liver Progenitor' as a predictor of survival independent of the clinical features. CONCLUSIONS: Response to neoadjuvant chemotherapy and survival in children treated for hepatoblastoma are associated with genomic and pathological features independently of the clinical features.

Engineering Novel 3D Models to Recreate High-Grade Osteosarcoma and its Immune and Extracellular Matrix Microenvironment.

Osteosarcoma (OS) is the most common primary bone cancer, where the overall 5-year surviving rate is below 20% in resistant forms. Accelerating cures for those poor outcome patients remains a challenge. Nevertheless, several studies of agents targeting abnormal cancerous pathways have yielded disappointing results when translated into clinic because of the lack of accurate OS preclinical modeling. So, any effort to design preclinical drug testing may consider all inter-, intra-, and extra-tumoral heterogeneities throughout models mimicking extracellular and immune microenvironment. Therefore, the bioengineering of patient-derived models reproducing the OS heterogeneity, the interaction with tumor-associated macrophages (TAMs), and the modulation of oxygen concentrations additionally to recreation of bone scaffold is proposed here. Eight 2D preclinical models mimicking several OS clinical situations and their TAMs in hypoxic conditions are developed first and, subsequently, the paired 3D models faithfully preserving histological and biological characteristics are generated. It is possible to shape reproducibly M2-like macrophages cultured with all OS patient-derived cell lines in both dimensions. The final 3D models pooling all heterogeneity features are providing accurate proliferation and migration data to understand the mechanisms involved in OS and immune cells/biomatrix interactions and sustained such that engineered 3D preclinical systems will improve personalized medicine.

Integrated Genomic Analysis Identifies Driver Genes and Cisplatin-Resistant Progenitor Phenotype in Pediatric Liver Cancer.

Pediatric liver cancers (PLC) comprise diverse diseases affecting infants, children, and adolescents. Despite overall good prognosis, PLCs display heterogeneous response to chemotherapy. Integrated genomic analysis of 126 pediatric liver tumors showed a continuum of driver mechanisms associated with patient age, including new targetable oncogenes. In 10% of patients with hepatoblastoma, all before three years old, we identified a mosaic premalignant clonal expansion of cells altered at the 11p15.5 locus. Analysis of spatial and longitudinal heterogeneity revealed an important plasticity between "hepatocytic," "liver progenitor," and "mesenchymal" molecular subgroups of hepatoblastoma. We showed that during chemotherapy, "liver progenitor" cells accumulated massive loads of cisplatin-induced mutations with a specific mutational signature, leading to the development of heavily mutated relapses and metastases. Drug screening in PLC cell lines identified promising targets for cisplatin-resistant progenitor cells, validated in mouse xenograft experiments. These data provide new insights into cisplatin resistance mechanisms in PLC and suggest alternative therapies. SIGNIFICANCE: PLCs are deadly when they resist chemotherapy, with limited alternative treatment options. Using a multiomics approach, we identified PLC driver genes and the cellular phenotype at the origin of cisplatin resistance. We validated new treatments targeting these molecular features in cell lines and xenografts.This article is highlighted in the In This Issue feature, p. 2355.

Tumor rupture in hepatoblastoma: A high risk factor?

BACKGROUND: Hepatoblastoma tumor rupture is a high-risk criterion in the SIOPEL 3/4 protocol. Little is known about the outcome of these children. METHODS: Radiological signs of possible tumor rupture, defined as peritoneal effusion, peritoneal nodules, or hepatic subcapsular hematoma, were reported in 24 of 150 patients treated for hepatoblastoma in France from January 2000 to December 2014 after central radiological expert review. RESULTS: Twenty-two patients with available clinical data were included (nine PRETEXT-I/II, six PRETEXT-III, seven PRETEXT-IV, and five had lung metastases). Five patients had a subcapsular hematoma only, and 17 patients had intraperitoneal rupture (subcapsular hematoma and peritoneal effusion). A hepatic biopsy was performed in 19 patients. Intraperitoneal rupture occurred before biopsy in 12 and after biopsy in three (including one with prebiopsy subcapsular hematoma) (missing data: two). All patients were treated with chemotherapy, with high-risk regimens including cisplatin or carboplatin and doxorubicin in 19 and cisplatin or carboplatin alone in three. Liver surgery was performed in 20 patients (including three liver transplants). Fifteen patients (68%) achieved complete remission. With a median follow-up of 5.5 years, 11 events occurred (six progressions and three relapses, including three peritoneal progressions/relapses, one surgical complication, and one second cancer) and eight patients died. One of eight patients with no other high-risk criterion had a relapse. The three-year event-free survival and overall survival rates were 49.6% (95% CI = 30-69) and 68.2% (40-84), respectively. CONCLUSIONS: Tumor rupture is predictive of poor prognosis with risk of peritoneal progression/relapse. However, it should not be a contraindication for liver transplantation.

Spinal cord atypical teratoid/rhabdoid tumors in children: Clinical, genetic, and outcome characteristics in a representative European cohort.

BACKGROUND: Case reports have portrayed spinal cord atypical teratoid/rhabdoid tumor (spATRT) as an aggressive form of ATRT. We conducted a retrospective European survey to collect data on clinical characteristics, molecular biology, treatment, and outcome of children with intramedullary spATRT. METHODS: Scrutinizing a French national series and the European Rhabdoid Registry database, we identified 13 patients (median age 32 months; metastatic disease at diagnosis, n = 6). Systemic postoperative chemotherapy was administered to all patients; three received intrathecal therapy and six were irradiated (craniospinal, n = 3; local, n = 3). RESULTS: Median observation time was 8 (range, 1-93) months. Progression-free and overall survival rates at 1 and (2 years) were 35.2% ± 13.9% (26.4% ± 12.9%) and 38.5% ± 13.5% (23.1% ± 11.7%). Four patients (ATRT-SHH, n = 2; ATRT-MYC, n = 1; DNA methylation subgroup not available, n = 1) achieved complete remission (CR); two of them are alive in CR 69 and 72 months from diagnosis. One patient relapsed after CR and is alive with progressive disease (PD) and one died of the disease. Three patients (ATRT-MYC, n = 2; subgroup not available, n = 1) died after 7 to 22 months due to PD after having achieved a partial remission (n = 1) or stabilization (n = 2). Five patients (ATRT-MYC, n = 2; subgroup not available, n = 3) developed early PD and died. One patient (ATRT-MYC) died of intracerebral hemorrhage prior to response evaluation. CONCLUSIONS: Long-term survival is achievable in selected patients with spATRT using aggressive multimodality treatment. Larger case series and detailed molecular analyses are needed to understand differences between spATRT and their inracranial counterparts and the group of extradural malignant rhabdoid tumors.

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 .).

Hepatocellular Carcinoma in Children: Does Modified Platinum- and Doxorubicin-Based Chemotherapy Increase Tumor Resectability and Change Outcome? Lessons Learned From the SIOPEL 2 and 3 Studies.

INTRODUCTION: The aim of this article is to present an experience of two prospective studies from the International Childhood Liver Tumor Strategy Group (SIOPEL 2 [S2] and SIOPEL [S3]) trials and to evaluate whether modified platinum- and doxorubicin-based chemotherapy is capable of increasing tumor resectability and changing patient outcomes. METHODS: Between 1995 and 2006, 20 patients with hepatocellular carcinoma (HCC) were included in the S2 trial and 70 were included in the S3 trial. Eighty-five patients remained evaluable. RESULTS: Response to preoperative chemotherapy was observed in 29 of 72 patients (40%) who did not have primary surgery, whereas 13 patients underwent upfront surgery. Thirty-three patients had a delayed resection. Thirty-nine tumors never became resectable. Complete tumor resection was achieved in 34 patients (40%), including seven of those treated with liver transplantation (LTX). After a median follow-up period of 75 months, 63 patients (74%) had an event (a progression during treatment, a relapse after treatment, or death from any cause). Sixty patients died. Twenty-three of 46 patients (50%) who underwent tumor resection died. Eighteen of 27 patients (63%) with complete tumor resection (without LTX) and 20 of 34 patients (59%) with LTX survived. Only one of seven patients (14%) with microscopically involved margins survived. Overall survival at 5 years was 22%. CONCLUSION: Survival in pediatric HCC is more likely when complete tumor resection can be achieved. Intensification of platinum agents in the S2 and S3 trials has not resulted in improved survival. New treatment approaches in pediatric HCC should be postulated.

Dose-dense cisplatin-based chemotherapy and surgery for children with high-risk hepatoblastoma (SIOPEL-4): a prospective, single-arm, feasibility study.

BACKGROUND: The objective of this study was to establish the efficacy and safety of a new treatment regimen consisting of dose-dense cisplatin-based chemotherapy and radical surgery in children with high-risk hepatoblastoma. METHODS: SIOPEL-4 was a prospective single-arm feasibility study. Patients aged 18 years or younger with newly diagnosed hepatoblastoma with either metastatic disease, tumour in all liver segments, abdominal extrahepatic disease, major vascular invasion, low α fetoprotein, or tumour rupture were eligible. Treatment consisted of preoperative chemotherapy (cycles A1-A3: cisplatin 80 mg/m(2) per day intravenous in 24 h on day 1; cisplatin 70 mg/m(2) per day intravenous in 24 h on days 8, 15, 29, 36, 43, 57, and 64; and doxorubicin 30 mg/m(2) per day intravenous in 24 h on days 8, 9, 36, 37, 57, and 58) followed by surgical removal of all remaining tumour lesions if feasible (including liver transplantation and metastasectomy, if needed). Patients whose tumour remained unresectable received additional preoperative chemotherapy (cycle B: doxorubicin 25 mg/m(2) per day in 24 h on days 1-3 and 22-24, and carboplatin area under the curve [AUC] 10·6 mg/mL per min per day intravenous in 1 h on days 1 and 22) before surgery was attempted. After surgery, postoperative chemotherapy was given (cycle C: doxorubicin 20 mg/m(2) per day in 24 h on days 1, 2, 22, 23, 43, and 44, and carboplatin AUC 6·6 mg/mL per min per day in 1 h on days 1, 22, and 43) to patients who did not receive cycle B. The primary endpoint was the proportion of patients with complete remission at the end of treatment. Analysis was by intention to treat. This trial is registered at ClinicalTrials.gov, NCT00077389. FINDINGS: We report the final analysis of the trial. 62 eligible patients (39 with lung metastases) were included and analysed. 60 (98%, 95% CI 91-100) of 61 evaluable patients (one child underwent primary hepatectomy) had a partial response to preoperative chemotherapy. Complete resection of all tumour lesions was achieved in 46 patients (74%). At the end of therapy, 49 (79%, 95% CI 67-88) of 62 patients were in complete remission. With a median follow-up of 52 months, 3-year event-free survival was 76% (95% CI 65-87) and 3-year overall survival was 83% (73-93). 60 (97%) patients had grade 3-4 haematological toxicity (anaemia, neutropenia, or thrombocytopenia) and 44 (71%) had at least one episode of febrile neutropenia. Other main grade 3 or 4 toxicities were documented infections (17 patients, 27%), anorexia (22, 35%), and mucositis (seven, 11%). One child died of fungal infection in neutropenia. Moderate-to-severe ototoxicity was documented in 31 (50%) patients. 18 serious adverse events (including two deaths) reflecting the observed side-effects were reported in the trial (the most common was ototoxicity in five patients). INTERPRETATION: The SIOPEL-4 treatment regimen is feasible and efficacious for complete remission at the end of treatment for patients with high-risk hepatoblastoma. FUNDING: Cancer Research UK and Cancer Research Switzerland/Oncosuisse.

[Paediatric malignant liver tumours]. / Tumeurs malignes primitives du foie de l'enfant.

Tumours and pseudotumours of the liver are a heterogeneous group of neoplasm including 60% of malignant tumours. Malignant liver tumours account for less than 2% of the lesions in children and vary considerably in incidence throughout the paediatric age range, with hepatoblastoma, rhabdoid tumour of the liver, hemangioendothelioma, biliary tract rhabdomysosarcoma and mesenchymal hamartoma in the first two years of life and hepatocellular carcinoma, focal nodular hyperplasia, and undifferentiated sarcoma in older children and adolescents. Treatment of malignant epithelial tumours is based on the surgical resection of the tumour associated with pre- and postoperative chemotherapy including cisplatinum. Modalities of the treatment are adapted to risk factors. Survival rates at three years are over 80% for localised hepatoblastoma whereas they are less than 30% in hepatocellular carcinomas. The role of targeted therapies still has to be defined.

Successful treatment of childhood high-risk hepatoblastoma with dose-intensive multiagent chemotherapy and surgery: final results of the SIOPEL-3HR study.

PURPOSE: The primary objective was to determine the efficacy of a newly designed preoperative chemotherapy regimen in an attempt to improve the cure rate of children with high-risk hepatoblastoma. PATIENTS AND METHODS: High risk was defined as follows: tumor in all liver sections (ie, Pretreatment Extension IV [PRETEXT-IV]), or vascular invasion (portal vein [P+], three hepatic veins [V+]), or intra-abdominal extrahepatic extension (E+), or metastatic disease, or alpha-fetoprotein less than 100 ng/mL at diagnosis. Patients were treated with alternating cycles of cisplatin and carboplatin plus doxorubicin (preoperatively, n = 7; postoperatively, n = 3) and delayed tumor resection. RESULTS: Of the 151 patients (150 evaluable for response) 118 (78.7%) achieved a partial response to chemotherapy. Complete resection of the liver tumor could be achieved in 115 patients (76.2%) either by partial hepatectomy (55.6%) or by liver transplantation (20.6%). In 106 children (70.2%), complete resection of all tumor lesions (including metastases) was achieved. Among the patients with initial lung metastases, 52.2% achieved complete remission of the lung lesions with chemotherapy alone. In half of the patients with initial PRETEXT-IV tumor as the only high-risk feature, the tumor could be completely resected with partial hepatectomy. Event-free (EFS) and overall survival (OS) estimates at 3 years were 65% (95% CI, 57% to 73%) and 69% (95% CI, 62% to 77%) for the whole group. EFS and OS for all patients with PRETEXT-IV tumor were 68% and 69%, respectively, and they were 56% and 62%, respectively, for patients with metastasis. CONCLUSION: The applied treatment rendered a great proportion of tumors resectable, and, in comparison with previously published results, led to an improved survival in patients with high-risk hepatoblastoma.

Cisplatin versus cisplatin plus doxorubicin for standard-risk hepatoblastoma.

BACKGROUND: Preoperative cisplatin alone may be as effective as cisplatin plus doxorubicin in standard-risk hepatoblastoma (a tumor involving three or fewer sectors of the liver that is associated with an alpha-fetoprotein level of >100 ng per milliliter). METHODS: Children with standard-risk hepatoblastoma who were younger than 16 years of age were eligible for inclusion in the study. After they received one cycle of cisplatin (80 mg per square meter of body-surface area per 24 hours), we randomly assigned patients to receive cisplatin (every 14 days) or cisplatin plus doxorubicin administered in three preoperative cycles and two postoperative cycles. The primary outcome was the rate of complete resection, and the trial was powered to test the noninferiority of cisplatin alone (<10% difference in the rate of complete resection). RESULTS: Between June 1998 and December 2006, 126 patients were randomly assigned to receive cisplatin and 129 were randomly assigned to receive cisplatin plus doxorubicin. The rate of complete resection was 95% in the cisplatin-alone group and 93% in the cisplatin-doxorubicin group in the intention-to-treat analysis (difference, 1.4%; 95% confidence interval [CI], -4.1 to 7.0); these rates were 99% and 95%, respectively, in the per-protocol analysis. Three-year event-free survival and overall survival were, respectively, 83% (95% CI, 77 to 90) and 95% (95% CI, 91 to 99) in the cisplatin group, and 85% (95% CI, 79 to 92) and 93% (95% CI, 88 to 98) in the cisplatin-doxorubicin group (median follow-up, 46 months). Acute grade 3 or 4 adverse events were more frequent with combination therapy (74.4% vs. 20.6%). CONCLUSIONS: As compared with cisplatin plus doxorubicin, cisplatin monotherapy achieved similar rates of complete resection and survival among children with standard-risk hepatoblastoma. Doxorubicin can be safely omitted from the treatment of standard-risk hepatoblastoma. (ClinicalTrials.gov number, NCT00003912.)

Relapses of optic pathway tumors after first-line chemotherapy.

BACKGROUND: Chemotherapy is accepted as first-line conservative treatment of optic pathway tumors in patients younger than 5. Limited data are available on the outcome of patients with recurrence/progression after initial chemotherapy. PROCEDURE: Data on 68 children with Optic Pathway Tumors (OPT) treated with first-line Baby Brain (BBSFOP) chemotherapy at the Gustave Roussy Institute in Villejuif between 1990 and 2005 were reviewed. RESULTS: During a median follow-up of 6 years, 44 (65%) patients were diagnosed with one or more relapses. Most of the relapses occurred during the first 6 years of life. Overall and progression-free survival rates at 5 years after first relapse were 64% and 14%, respectively. First relapse was treated with chemotherapy, radiotherapy or surgery in 28, 9, and 6 patients, respectively. Best response to second-line chemotherapy was partial response in 10, stable disease in 10, and progressive disease in 8 patients. Patients with objective radiologic response to first-line chemotherapy, had a greater chance to respond again to second-line chemotherapy (RR = 90% vs. 15%, P = 0.003). Median time to progression after first relapse was 1.7, 2.5, and 3.1 years after surgery, chemotherapy and radiotherapy, respectively. Finally, 25 (37%) patients received radiotherapy at a median age of 6.7 years. CONCLUSIONS: Second-line chemotherapy can be effective in the treatment of relapses after first-line chemotherapy and delay further the need for RT, especially in patients whose tumor initially responded to chemotherapy. Despite the desire to avoid irradiation in treatment of young patients with OPT, radiotherapy was used for 37% of patients, usually before the age of 10.

Hepatic stem-like phenotype and interplay of Wnt/beta-catenin and Myc signaling in aggressive childhood liver cancer.

Hepatoblastoma, the most common pediatric liver cancer, is tightly linked to excessive Wnt/beta-catenin signaling. Here, we used microarray analysis to identify two tumor subclasses resembling distinct phases of liver development and a discriminating 16-gene signature. beta-catenin activated different transcriptional programs in the two tumor types, with distinctive expression of hepatic stem/progenitor markers in immature tumors. This highly proliferating subclass was typified by gains of chromosomes 8q and 2p and upregulated Myc signaling. Myc-induced hepatoblastoma-like tumors in mice strikingly resembled the human immature subtype, and Myc downregulation in hepatoblastoma cells impaired tumorigenesis in vivo. Remarkably, the 16-gene signature discriminated invasive and metastatic hepatoblastomas and predicted prognosis with high accuracy.

[Malignant rhabdoid tumor of the liver with spontaneous rupture: a case report]. / Tumeur rhabdoïde hépatique maligne avec rupture spontanée: à propos d'un cas.

We report the case of an 8-year-old child, presenting a rhabdoid tumor of the liver with spontaneous rupture, revealed by an intra-abdominal bleeding with rapidly fatal course. This clinical and pathological report raises the problem of the differential diagnosis of primary malignant hepatic tumors of the child with no alpha-foetoprotein increase.

Progression-free survival in children with optic pathway tumors: dependence on age and the quality of the response to chemotherapy--results of the first French prospective study for the French Society of Pediatric Oncology.

PURPOSE: To evaluate a strategy aimed at avoiding radiotherapy during first-line treatment of children with progressive optic pathway tumors (OPT), by exclusively administering multiagent chemotherapy during 16 months. PATIENTS AND METHODS: Between 1990 and 1998, 85 children with progressive OPT were enrolled onto this multicenter nationwide trial. Chemotherapy alternating procarbazine plus carboplatin, etoposide plus cisplatin, and vincristine plus cyclophosphamide was given every 3 weeks. At the time of relapse or progression, second-line chemotherapy was authorized before recourse to radiotherapy. RESULTS: Objective response rate (partial response [PR] + complete response [CR]) to chemotherapy was 42%. Five-year progression-free survival (PFS) and overall survival rates were 34% and 89%, respectively. The 5-year radiotherapy-free survival rate was 61%. In the multivariate analysis of the 85 patients that entered onto the study, factors associated with the risk of disease progression were age younger than 1 year at diagnosis (P =.047) and absence of neurofibromatosis type 1 (P =.035). In the multivariate analysis of the 74 patients that remained on study after the first cycle of chemotherapy, factors associated with the risk of disease progression were age younger than 1 year at diagnosis (P =.0053) and no objective response to chemotherapy (P =.0029). Three-year PFS was 44% in infants < or = 1 year versus 66% in children older than 1 year. Three-year PFS was 53% in the absence of an objective response to chemotherapy versus 68% after a PR or CR. CONCLUSION: A significant proportion of children with OPT can avoid radiotherapy after prolonged chemotherapy. Deferring irradiation with chemotherapy protocols did not compromise overall survival of the entire population or visual function.

Sensitivity to radiation and alkylating agent of peripheral lymphocytes and fibroblasts in a Hoyeraal-Hreidarsson syndrome patient.

Hoyeraal-Hreidarsson syndrome (HHS) is a severe infantile variant of X-linked dyskeratosis congenita (DC). The authors report evidence of increased in vitro sensitivity to radiation and alkylating agent in circulating lymphocytes and fibroblasts obtained from a 7-year-old boy with HHS. A major telomere shortening was also found (3 kb) as compared to healthy donors (10 kb). The standard treatments, chemotherapy regimens, and radiation therapy were not possible. The data suggest that conditioning regimens including TBI should not be used when a bone marrow transplantation procedure is planned in these patients.