Liver transplantation for primary liver tumors in pediatrics. A case series. / Trasplante hepático para tumores hepáticos primarios en pediatría. Serie de casos.

Primary liver tumors are an increasing indication for pediatric liver transplantation. Here we report the cases of 10 patients who underwent liver transplantation for primary liver tumors in our hospital, from 2001 to date. Up to 2011, 1 transplant due to hepatoblastoma was done out of 117 liver transplants (0.8%). Since 2012, there were 9 patients out of 141 (6.4%) (5 due to hepatoblastoma, 2 due to hepatocellular carcinoma, 1 due to hepatic epithelioid hemangioendothelioma, and 1 due to hepatic mesenchymal hamartoma). Follow-up: 13.2 months (median); age at transplantation: living 4.7 years (median); weight: 17.6 kg (median). Eighty percent of patients received grafts from living donors. No tumor recurrence was observed. Survival was 100% in the follow-up period. In our series, patients with primary liver tumors requiring transplantation showed an adequate course, even in the case of hepatocellular carcinoma, Related living donors liver transplantation shortened the time between the indication and the surgery.

Los tumores hepáticos primarios son indicación creciente de trasplante hepático pediátrico. Reportamos los 10 pacientes con trasplantes hepáticos por tumores hepáticos primarios en nuestro centro desde 2001 hasta la actualidad. Hasta el año 2011, se realizó un trasplante por hepatoblastoma de 117 trasplantes hepáticos (0,8 %). Desde 2012, fueron 9 pacientes de 141 (6,4 %) (5 hepatoblastomas, 2 hepatocarcinomas, 1 hemangioendotelioma epitelioide hepático y 1 hamartoma mesenquimático hepático). Seguimiento 13,2 meses (media), edad al trasplante 4,7 años (media), peso 17,6 kg (mediana). El 80 % recibió injertos desde donantes relacionados. No hubo recurrencia tumoral y la sobrevida fue del 100 % en el período de seguimiento. En nuestra serie, los pacientes con tumores hepáticos primarios que requirieron trasplante presentaron buena evolución, aun en hepatocarcinoma. El trasplante hepático con donante relacionado acortó los tiempos entre la indicación y la realización.

Case Report: ALPPS hepatectomy, an alternative to liver transplantation in central PRETEXT III hepatoblastomas: a case series.

Introduction: Hepatoblastoma is the most common malignant primary liver tumor in the pediatric population, accounting for 67% of cases in the United States. Surgical resection is the only curative treatment option; however, it can be performed in only 10% of patients with primary tumors. The two most common limitations for resection are the need for extensive resections and tumors in central locations. The therapeutic hypertrophy of healthy tissue achieved with ALPPS (Associating Liver Partition and Portal vein ligation for Staged Hepatectomy) enables larger resections and has been successfully employed in the pediatric population in recent years. Objective: To present three cases of patients with centrally located PRETEXT II or III hepatoblastomas who underwent ALPPS procedure as a viable therapeutic alternative to liver transplantation. Discussion and results: Central PRETEXT III hepatoblastomas are typically indications for liver transplantation. Transplantation offers high five-year survival rates (73%). However, the associated morbidity, healthcare system costs, and limited availability make it necessary to explore alternative options. Series have reported the successful application of the ALPPS procedure in PRETEXT II and PRETEXT III hepatoblastomas in other locations. Therapeutically induced hypertrophy, characterized by an increase in the volume of healthy tissue in unaffected lobes or segments, enabled the resection of previously deemed unresectable lesions. The patients experienced uncomplicated postoperative courses and expected reduction in tumor markers. Chemotherapy selection followed the guidelines outlined in Block C of the SIOPEL IV protocol. Conclusions: ALPPS hepatectomy is a viable therapeutic option for patients with centrally located PRETEXT III or II hepatoblastomas.

First Transcriptome Analysis of Hepatoblastoma in Brazil: Unraveling the Pivotal Role of Noncoding RNAs and Metabolic Pathways.

Hepatoblastoma stands as the most prevalent liver cancer in the pediatric population. Characterized by a low mutational burden, chromosomal and epigenetic alterations are key drivers of its tumorigenesis. Transcriptome analysis is a powerful tool for unraveling the molecular intricacies of hepatoblastoma, shedding light on the effects of genetic and epigenetic changes on gene expression. In this study conducted in Brazilian patients, an in-depth whole transcriptome analysis was performed on 14 primary hepatoblastomas, compared to control liver tissues. The analysis unveiled 1,492 differentially expressed genes (1,031 upregulated and 461 downregulated), including 920 protein-coding genes (62%). Upregulated biological processes were linked to cell differentiation, signaling, morphogenesis, and development, involving known hepatoblastoma-associated genes (DLK1, MEG3, HDAC2, TET1, HMGA2, DKK1, DKK4), alongside with novel findings (GYNG4, CDH3, and TNFRSF19). Downregulated processes predominantly centered around oxidation and metabolism, affecting amines, nicotinamides, and lipids, featuring novel discoveries like the repression of SYT7, TTC36, THRSP, CCND1, GCK and CAMK2B. Two genes, which displayed a concordant pattern of DNA methylation alteration in their promoter regions and dysregulation in the transcriptome, were further validated by RT-qPCR: the upregulated TNFRSF19, a key gene in the embryonic development, and the repressed THRSP, connected to lipid metabolism. Furthermore, based on protein-protein interaction analysis, we identified genes holding central positions in the network, such as HDAC2, CCND1, GCK, and CAMK2B, among others, that emerged as prime candidates warranting functional validation in future studies. Notably, a significant dysregulation of non-coding RNAs (ncRNAs), predominantly upregulated transcripts, was observed, with 42% of the top 50 highly expressed genes being ncRNAs. An integrative miRNA-mRNA analysis revealed crucial biological processes associated with metabolism, oxidation reactions of lipids and carbohydrates, and methylation-dependent chromatin silencing. In particular, four upregulated miRNAs (miR-186, miR-214, miR-377, and miR-494) played a pivotal role in the network, potentially targeting multiple protein-coding transcripts, including CCND1 and CAMK2B. In summary, our transcriptome analysis highlighted disrupted embryonic development as well as metabolic pathways, particularly those involving lipids, emphasizing the emerging role of ncRNAs as epigenetic regulators in hepatoblastomas. These findings provide insights into the complexity of the hepatoblastoma transcriptome and identify potential targets for future therapeutic interventions.

Hepatoblastoma en un paciente pediátrico a propósito de un caso

La incidencia de hepatoblastoma alrededor del mundo permanece constante entre 0.5 y 1.5 casos por millón de niños por año. En los Estados Unidos de América se reporta para el hepatoblastoma una incidencia anual de aproximadamente 1 por millón en niños menores de 15 años de edad. En Ecuador, en una investigación realizada en la ciudad de Cuenca, ocupa el séptimo lugar entre los tumores pediátricos. Se trata de un tumor infrecuente, cuya incidencia parece aumentar en los últimos años. Puede aparecer de forma aislada o integrarse en el contexto de un síndrome de predisposición. Presentamos el caso de un paciente pediátrico, femenina, preescolar de 3 años de edad, sin antecedentes perinatales de importancia, producto de la tercera gesta, nacida por cesárea por distocia de presentación a las 39 semanas. Cuenta con esquema de vacunación completo para la edad. Como antecedentes patológicos personales requiere una hospitalización por enfermedad diarreica aguda a los 2 años. Sin antecedentes quirúrgicos, antecedentes patológicos familiares de tía materna con hipotiroidismo. Se realizó exámenes complementarios de sangre y de imagen, los cuales revelaron una masa abdominal dependiente de hígado compatible con hepatoblastoma con niveles de AFP superiores a 1000ng/ml

The incidence of hepatoblastoma around the world remains constant between 0.5 and 1.5 cases per million children per year. In the United States of America, an annual incidence of approximately 1 per million is reported for hepatoblastoma in children under 15 years of age. In Ecuador, in a study carried out in the city of Cuenca, it ranks seventh among pediatric tumors. It is an infrequent tumor, its incidence seems to have increased in recent years. It can appear in isolation or be part of a predisposing syndrome. We present the case of a 3-year-old preschool female pediatric patient with no significant perinatal history, product of a third pregnancy, born by cesarean section due to presentation of dystocia at 39 weeks. She had a complete vaccination for her age. As past medical history, she was hospitalized for acute diarrheal disease at 2 years of age. She had no surgical history, family pathological history except for a maternal aunt with hypothyroidism. Complementary blood and imaging tests were performed, which revealed an abdominal liver-dependent mass, compatible with hepatoblastoma with AFP levels greater than 1000 ng/ml.

High-Resolution Magic-Angle-Spinning NMR in Revealing Hepatoblastoma Hallmarks.

Cancer is one of the leading causes of death in children and adolescents worldwide; among the types of liver cancer, hepatoblastoma (HBL) is the most common in childhood. Although it affects only two to three individuals in a million, it is mostly asymptomatic at diagnosis, so by the time it is detected it has already advanced. There are specific recommendations regarding HBL treatment, and ongoing studies to stratify the risks of HBL, understand the pathology, and predict prognostics and survival rates. Although magnetic resonance imaging spectroscopy is frequently used in diagnostics of HBL, high-resolution magic-angle-spinning (HR-MAS) NMR spectroscopy of HBL tissues is scarce. Using this technique, we studied the alterations among tissue metabolites of ex vivo samples from (a) HBL and non-cancer liver tissues (NCL), (b) HBL and adjacent non-tumor samples, and (c) two regions of the same HBL samples, one more centralized and the other at the edge of the tumor. It was possible to identify metabolites in HBL, then metabolites from the HBL center and the border samples, and link them to altered metabolisms in tumor tissues, highlighting their potential as biochemical markers. Metabolites closely related to liver metabolisms such as some phospholipids, triacylglycerides, fatty acids, glucose, and amino acids showed differences between the tissues.

Infrecuente tumor hepatico: Hepatoblastoma. Caso Clínico

Objetivo: Comunicar el primer caso de hepatoblastoma adulto en Uruguay. Actualmente existen 69 casos reportados en la literatura internacional. Materiales y Método: Revisión de historia clínica de paciente de 33 años, sexo femenino. Operada en 2017 con diagnóstico de tumor estromal gástrico. En la exploración se constató tumoración hepática en lóbulo izquierdo que se biopsia. Resultado: neoplasia maligna de estirpe epitelial-carcinoma- diferenciación neuroendócrina. Pobre respuesta a tratamiento neoadyuvante. PET/CT evidenció ausencia de captación con DOTATATE asociado a actividad metabólica con FDG que sugiere TNE poco diferenciado. Se realiza segmentectomía II - III, colecistectomía y esplenectomía por implante en superficie esplénica. Anatomía patológica: hepatoblastoma subtipo epitelial. Bazo sin infiltración. Bordes de resección hepática libres de tumor. Resultados: Buena evolución postoperatoria. Al momento del reporte la paciente tiene una sobrevida de 47 meses bajo quimioterapia. Conclusiones: El hepatoblastoma en el adulto se caracteriza por una evolución agresiva y de mal pronóstico. Su diagnóstico es exclusivamente histológico. La única terapia pretendidamente curativa es la resección completa como lo fue en nuestra paciente. La sobrevida en menores de 45 años con tratamiento quirúrgico es de 12 meses.

Aim: To communicate the first adult hepatoblastoma case in Uruguay. There are only 69 adult cases re- ported in the international literature. Materials and Method: Review of the clinical history of a 33 year old female patient. During surgery of gastric estromal tumor in 2017, exploration on the left hepatic lobe found a tumor which biopsy showed a malignant neoplasy of a epitelial carcinoma with neuroendocrine differenciation. Poor response to neadyuvant treatment. PET/CT negative for DOTATATE, but positive caption with FDG that suggest poor differenciate neuroendocrine tumor. Hepatic surgery was performed with II and III segmentectomy, cholecistectomy and splenectomy because tumor implants on the surface. Results: Pathological anatomy: hepatoblastoma with epithelial differenciation. No infiltration of the spleen. Tumor margins negative. Good postoperative evolution with 47 months of survival under chemotherapy at the time of this report. Conclusions: Adult hepatoblastoma is an agressive tumor with high rates of recurrence and bad prognoses. The only diagnose is by histological findings. The only curative treatment is the surgical resection, as on our case. The survival of patients under 45 years old, with surgical treatment is generally 12 months.

Bone metastases in hepatoblastoma, an unusual presentation. Case report and review of the literature.

Primary liver tumors are rare in childhood. Hepatoblastoma is the most prevalent and has a variable clinical presentation. The initial approach requires clinical suspicion, histopathological confirmation, and measurement of AFP levels, in addition to PRETEXT staging by abdominal computed tomography. PET-CT is useful in metastatic disease for diagnosis and evaluation of therapeutic response. Pulmonary metastases at the time of diagnosis are frequent, while bone metastases are rare. We present the case of an infant with a history of metastatic hepatoblastoma, multiple relapses, and poor response to multimodal management. The patient had bone metastases demonstrated by PET-CT imaging.

Unraveling the Genetic Architecture of Hepatoblastoma Risk: Birth Defects and Increased Burden of Germline Damaging Variants in Gastrointestinal/Renal Cancer Predisposition and DNA Repair Genes.

The ultrarare hepatoblastoma (HB) is the most common pediatric liver cancer. HB risk is related to a few rare syndromes, and the molecular bases remain elusive for most cases. We investigated the burden of rare damaging germline variants in 30 Brazilian patients with HB and the presence of additional clinical signs. A high frequency of prematurity (20%) and birth defects (37%), especially craniofacial (17%, including craniosynostosis) and kidney (7%) anomalies, was observed. Putative pathogenic or likely pathogenic monoallelic germline variants mapped to 10 cancer predisposition genes (CPGs: APC, CHEK2, DROSHA, ERCC5, FAH, MSH2, MUTYH, RPS19, TGFBR2 and VHL) were detected in 33% of the patients, only 40% of them with a family history of cancer. These findings showed a predominance of CPGs with a known link to gastrointestinal/colorectal and renal cancer risk. A remarkable feature was an enrichment of rare damaging variants affecting different classes of DNA repair genes, particularly those known as Fanconi anemia genes. Moreover, several potentially deleterious variants mapped to genes impacting liver functions were disclosed. To our knowledge, this is the largest assessment of rare germline variants in HB patients to date, contributing to elucidate the genetic architecture of HB risk.

Primary Malignant Liver Tumors: eight-year experience in a Pediatric Hospital in Brazil. A cross-sectional study / Neoplasias Malignas Primárias do Fígado: experiência de oito anos de um Hospital Pediátrico no Brasil. Estudo transversal

ABSTRACT Introduction: liver tumors are rare neoplasms in childhood (1-2%), and about 2/3 are malignant. Hepatoblastoma (HB) is the most frequent, followed by hepatocellular carcinoma (HCC). In both, the main treatment is surgical resection. Currently, chemotherapy and liver transplantation have improved outcomes. Objective: study of the epidemiological profile and evolution of liver cancer cases in a referral pediatric hospital. Methodology: a retrospective survey of medical records of patients aged up to 18 years with a diagnosis of primary malignant hepatic neoplasm between 2012 and 2020, carried out in the largest exclusively pediatric hospital in Brazil. Results: a total of 13 patients with malignant liver tumors (HB 12, HCC 1) were treated. Of the HB cases, 66,7% were male, with a mean age of 2 years and the main alteration in the palpable abdominal mass. Tumors involved an average of 3 liver segments, more in the right lobe (54%). Only one patient was treated with surgery without neoadjuvant therapy, another one underwent transplantation like the first treatment, and another 2 required liver transplantation as a rescue. The middle follow-up time of patients with HB was 39 months and only 1 case died due to febrile neutropenia. The 5-year overall and disease-free survival was 91.7% and 81.5%, respectively. Conclusion: Advanced staging at the time of diagnosis has always been a poor prognostic factor in patients with primary malignant liver tumors. However, the results and survival have improved with the advancement of chemotherapy, surgical technique, and liver transplantation.

RESUMO Introdução: tumores hepáticos são neoplasias raras na infância (1-2%), sendo que cerca de 2/3 são malignos. O hepatoblastoma (HB) é o mais frequente, seguido do carcinoma hepatocelular (CHC). Em ambos, o principal tratamento é a ressecção cirúrgica completa. Atualmente, a quimioterapia e o transplante hepático têm melhorado os resultados. Objetivo: estudo do perfil epidemiológico e evolução dos casos de cânceres hepáticos em um hospital pediátrico de referência. Método: Levantamento retrospectivo de prontuários de pacientes até 18 anos com diagnóstico de neoplasia maligna primária hepática entre 2012 e 2020 realizado no maior hospital exclusivamente pediátrico do Brasil. Resultados: foram atendidos 13 pacientes com tumores malignos hepáticos (HB 12, CHC 1). Dos casos de HB, 66,7% eram do sexo masculino, com idade média de 2 anos e a principal alteração foi massa abdominal palpável. Os tumores envolviam em média 3 segmentos hepáticos, mais em lobo direito (54%). Um paciente foi tratado com cirurgia sem neoadjuvância, um foi submetido a transplante inicialmente e outros 2 necessitaram de transplante hepático como resgate. O tempo de seguimento dos pacientes com HB foi de 39 meses e apenas 1 caso foi a óbito por neutropenia febril. A sobrevida geral e livre de doença em 5 anos foi de 91,7% e 81,5% respectivamente. Conclusão: o estadiamento avançado no momento do diagnóstico sempre foi um fator de mau prognóstico em pacientes com tumores hepáticos malignos primários. Entretanto, os resultados e a sobrevida têm melhorado significativamente com o avanço da quimioterapia, da técnica cirúrgica e do transplante hepático.

Copy Number Alterations in Hepatoblastoma: Literature Review and a Brazilian Cohort Analysis Highlight New Biological Pathways.

Hepatoblastoma (HB) is a rare embryonal tumor, although it is the most common pediatric liver cancer. The aim of this study was to provide an accurate cytogenomic profile of this type of cancer, for which information in cancer databases is lacking. We performed an extensive literature review of cytogenetic studies on HBs disclosing that the most frequent copy number alterations (CNAs) are gains of 1q, 2/2q, 8/8q, and 20; and losses at 1p and 4q. Furthermore, the CNA profile of a Brazilian cohort of 26 HBs was obtained by array-CGH; the most recurrent CNAs were the same as shown in the literature review. Importantly, HBs from female patients, high-risk stratification tumors, tumors who developed in older patients (> 3 years at diagnosis) or from patients with metastasis and/or deceased carried a higher diversity of chromosomal alterations, specifically chromosomal losses at 1p, 4, 11q and 18q. In addition, we distinguished three major CNA profiles: no detectable CNA, few CNAs and tumors with complex genomes. Tumors with simpler genomes exhibited a significant association with the epithelial fetal subtype of HBs; in contrast, the complex genome group included three cases with epithelial embryonal histology, as well as the only HB with HCC features. A significant association of complex HB genomes was observed with older patients who developed high-risk tumors, metastasis, and deceased. Moreover, two patients with HBs exhibiting complex genomes were born with congenital anomalies. Together, these findings suggest that a high load of CNAs, mainly chromosomal losses, particularly losses at 1p and 18, increases the tendency to HB aggressiveness. Additionally, we identified six hot-spot chromosome regions most frequently affected in the entire group: 1q31.3q42.3, 2q23.3q37.3, and 20p13p11.1 gains, besides a 5,3 Mb amplification at 2q24.2q24.3, and losses at 1p36.33p35.1, 4p14 and 4q21.22q25. An in-silico analysis using the genes mapped to these six regions revealed several enriched biological pathways such as ERK Signaling, MicroRNAs in Cancer, and the PI3K-Akt Signaling, in addition to the WNT Signaling pathway; further investigation is required to evaluate if disturbances of these pathways can contribute to HB tumorigenesis. The analyzed gene set was found to be associated with neoplasms, abnormalities of metabolism/homeostasis and liver morphology, as well as abnormal embryonic development and cytokine secretion. In conclusion, we have provided a comprehensive characterization of the spectrum of chromosomal alterations reported in HBs and identified specific genomic regions recurrently altered in a Brazilian HB group, pointing to new biological pathways, and relevant clinical associations.

Resultados del tratamiento del hepatoblastoma en los Andes Ecuatorianos / Results of the treatment of hepatoblastoma in the Ecuadorian Andes

RESUMEN: El hepatoblastoma (HB), es una neoplasia maligna, que se origina en el hígado. La supervivencia (SV) depende de la extensión de avance de la enfermedad. El objetivo de este estudio fue determinar diferencias en la SV actuarial global (SVAG) y libre de enfermedad (SVLE) en pacientes con HB, según la extensión de su enfermedad. Serie de casos con seguimiento. Se incluyeron pacientes de entre 4 y 160 meses de edad tratados en un centro oncológico de Los Andes ecuatorianos (2000-2019). Las variables resultado fueron: lóbulo afectado, metástasis pulmonar, infiltración vascular, estadio PRETEXT, riesgo, histología, niveles de alfafetoproteína (AFP), remisión completa (RC), SVAG y SVLE. Se utilizó estadística descriptiva y analítica (Chi2, exacto de Fisher y corrección por continuidad). Se realizaron análisis de SV con curvas de Kaplan Meier y log-rank. Fueron estudiados 28 pacientes (53,6 % hombres), con una mediana de edad de 40 meses. Se verificaron metástasis pulmonares e infiltración vascular en el 25,0 % y 35,7 % de los casos respectivamente. La histología, estadio clínico y riesgo alto fueron mayoritariamente tipo epitelial (42,8 %), PRETEXT II (50,0 %) y riesgo alto (67,8 %) respectivamente. La media de AFP al diagnóstico fue 1055712ng/ml y 9 pacientes alcanzaron RC. La SVAG y SVLE general a 19 años fue 33,1 % y 26,0 % respectivamente. Según su extensión, la SVAG y la SVLE para los pacientes de riesgo estándar y alto fueron 50,0 % y 25,4 % (p=0,148); y 50,0 % y 14,7 % (p=0,037) respectivamente. La SVAG y SVLE verificadas son menores a las reportadas en otros estudios. La SVLE según su extensión, presentó diferencia significativa, sin embargo, este resultado debe ser tomado con cautela debido al número pequeño de pacientes.

SUMMARY: Hepatoblastoma (HB), is a malignant neoplasm, which originates in the liver. Survival (SV) depends on the extent of disease progression. The objective of this study was to determine differences in overall SV (OS) and disease-free (DFS) in patients with HB, according to the extent of their disease. Case series with follow-up. Patients between 4 and 160 months of age treated at an oncology center in the Ecuadorian Andes (2000-2019) were included. The result variables were affected lobe, lung metastasis, vascular infiltration, PRETEXT stage, risk, histology, alpha-fetoprotein levels (AFP), complete remission (RC), OS and DFS. Descriptive and analytical statistics (Chi2, Fisher's exact and continuity correction) were used. SV analyzes were performed with Kaplan Meier and log-rank curves. In this analysis 28 patients (53.6 % men), with a median age of 40 months, were studied. Lung metastases and vascular infiltration were verified in 25.0 % and 35.7 % of the cases, respectively. Histology, clinical stage, and high risk were mainly epithelial type (42.8 %), PRETEXT II (50.0 %), and high risk (67.8 %), respectively. The mean AFP at diagnosis was 1055712 ng / ml and 9 patients achieved CR. OS and DFS at 19 years were 33.1 % and 26.0 % respectively. According to their extension, the OS and DFS for standard and high risk patients were 50.0 % and 25.4 % (p = 0.148); and 50.0 % and 14.7 % (p = 0.037) respectively. The verified OS and DFS are lower than those reported in other studies. DFS according to its extension, presented a significant difference, however, this result should be considered with caution due to the small number of patients.

HDAC1-Dependent Repression of Markers of Hepatocytes and P21 Is Involved in Development of Pediatric Liver Cancer.

BACKGROUND & AIMS: Epigenetic regulation of gene expression plays a critical role in the development of liver cancer; however, the molecular mechanisms of epigenetic-driven liver cancers are not well understood. The aims of this study were to examine molecular mechanisms that cause the dedifferentiation of hepatocytes into cancer cells in aggressive hepatoblastoma and test if the inhibition of these mechanisms inhibits tumor growth. METHODS: We have analyzed CCAAT/Enhancer Binding Protein alpha (C/EBPα), Transcription factor Sp5, and histone deacetylase (HDAC)1 pathways from a large biobank of fresh hepatoblastoma (HBL) samples using high-pressure liquid chromatography-based examination of protein-protein complexes and have examined chromatin remodeling on the promoters of markers of hepatocytes and p21. The HDAC1 activity was inhibited in patient-derived xenograft models of HBL and in cultured hepatoblastoma cells and expression of HDAC1-dependent markers of hepatocytes was examined. RESULTS: Analyses of a biobank showed that a significant portion of HBL patients have increased levels of an oncogenic de-phosphorylated-S190-C/EBPα, Sp5, and HDAC1 compared with amounts of these proteins in adjacent regions. We found that the oncogenic de-phosphorylated-S190-C/EBPα is created in aggressive HBL by protein phosphatase 2A, which is increased within the nucleus and dephosphorylates C/EBPα at Ser190. C/EBPα-HDAC1 and Sp5-HDAC1 complexes are abundant in hepatocytes, which dedifferentiate into cancer cells. Studies in HBL cells have shown that C/EBPα-HDAC1 and Sp5-HDAC1 complexes reduce markers of hepatocytes and p21 via repression of their promoters. Pharmacologic inhibition of C/EBPα-HDAC1 and Sp5-HDAC1 complexes by Suberoylanilide hydroxamic acid (SAHA) and small interfering RNA-mediated inhibition of HDAC1 increase expression of hepatocyte markers, p21, and inhibit proliferation of cancer cells. CONCLUSIONS: HDAC1-mediated repression of markers of hepatocytes is an essential step for the development of HBL, providing background for generation of therapies for aggressive HBL by targeting HDAC1 activities.

DNA methylation as a key epigenetic player for hepatoblastoma characterization.

BACKGROUND: Hepatoblastoma (HB) is a rare embryonal liver tumor of children. Although intrinsic biological differences between tumors can affect prognosis, few groups have studied these differences. Given the recent increased attention to epigenetic mechanisms in the genesis and progression of these tumors, we aimed to classify HB samples according to the stages of liver development and DNA methylation machinery. BASIC PROCEDURES: We evaluated the expression of 24 genes associated with DNA methylation and stages of hepatocyte differentiation and global DNA methylation. Using bioinformatics tools and expression data, we propose a stratification model for HB. MAIN FINDINGS: Tumors clustered into three groups that presented specific gene expression profiles of the panel of DNA methylation enzymes and hepatocyte differentiation markers. In addition to reinforcing these embryonal tumors' molecular heterogeneity, we propose that a panel of 13 genes can stratify HBs (TET1, TET2, TET3, DNMT1, DNMT3A, UHRF1, ALB, CYP3A4, TDO2, UGT1A1, AFP, HNF4A, and FOXA2). DNA methylation machinery participates in the characterization of HBs, directly reflected in diverse DNA methylation content. The data suggested that a subset of HBs were similar to differentiated livers, with upregulation of mature hepatocyte markers, decreased expression of DNA methylation enzymes, and higher global methylation levels; these findings might predict worse outcomes. CONCLUSIONS: HBs are heterogeneous tumors. Despite using a small cohort of 21 HB samples, our findings reinforce that DNA methylation is a robust biomarker for this tumor type.

Management of Pediatric Tumors With Vascular Extension.

Background: Pediatric tumors can present with vascular extension to the inferior vena cava and right atrium, which impacts the surgical strategy and can be challenging during surgical treatment. Wilms tumor (WT) is the most common retroperitoneal tumor that can present with vascular extension, but also adrenal tumors, clear cell tumors from the kidney, and hepatoblastomas can present with this situation. Surgical aims include obtaining complete tumor resection without risk for patients, to avoid severe bleeding, cardiac arrest, and embolization, and to avoid cardiac bypass if possible. Objective: To describe and discuss the surgical strategies to deal with pediatric tumors with vascular extension and propose a protocol. Method: Retrospectivly review the experience of treating patients with vascular extension in a single institution, describing different scenarios and a decision making fluxogram based on the preoperative evaluation regarding the surgical techniques and the need for cardiac bypass that are adequate for each situation. Image studies are important to guide the surgical strategy. Depending on the quality of image available, computerized tomography (CT) or magnetic resonance imaging (MRI) can be enough to give the information needed for surgical decisions. Ultrasonography (US) with Doppler is helpful to confirm diagnosis and describes factors to guide the adequate surgical strategy, like the upper level extension and presence or absence of blood flow around the thrombus. Neoadjuvant chemotherapy is indicated in most cases, in order to reduce the upper level of extension (and avoid the need for cardiac bypass) and to lower the risk of embolization. The approach is based on the upper level of the thrombus and can include cavotomy or cavectomy, sometimes with cardiac bypass and cardiac arrest with hypothermia, when the thrombus reaches the diaphragmatic level or above. Pathology analysis of the thrombus can guide staging and the need for radiotherapy postoperatively. Results: A decision making fluxogram protocol is presented focusing on the surgical treatment of such condition. Conclusion: Surgery strategy is highly impacted by the presence of vascular extension in pediatric tumors. Surgeons should be aware of potential complications and how to prevent them. Such cases should be treated in reference centers.

Hepatoblastomas exhibit marked NNMT downregulation driven by promoter DNA hypermethylation.

Hepatoblastomas exhibit the lowest mutational burden among pediatric tumors. We previously showed that epigenetic disruption is crucial for hepatoblastoma carcinogenesis. Our data revealed hypermethylation of nicotinamide N-methyltransferase, a highly expressed gene in adipocytes and hepatocytes. The expression pattern and the role of nicotinamide N-methyltransferase in pediatric liver tumors have not yet been explored, and this study aimed to evaluate the effect of nicotinamide N-methyltransferase hypermethylation in hepatoblastomas. We evaluated 45 hepatoblastomas and 26 non-tumoral liver samples. We examined in hepatoblastomas if the observed nicotinamide N-methyltransferase promoter hypermethylation could lead to dysregulation of expression by measuring mRNA and protein levels by real-time quantitative polymerase chain reaction, immunohistochemistry, and Western blot assays. The potential impact of nicotinamide N-methyltransferase changes was evaluated on the metabolic profile by high-resolution magic angle spinning nuclear magnetic resonance spectroscopy. Significant nicotinamide N-methyltransferase downregulation was revealed in hepatoblastomas, with two orders of magnitude lower nicotinamide N-methyltransferase expression in tumor samples and hepatoblastoma cell lines than in hepatocellular carcinoma cell lines. A specific TSS1500 CpG site (cg02094283) of nicotinamide N-methyltransferase was hypermethylated in tumors, with an inverse correlation between its methylation level and nicotinamide N-methyltransferase expression. A marked global reduction of the nicotinamide N-methyltransferase protein was validated in tumors, with strong correlation between gene and protein expression. Of note, higher nicotinamide N-methyltransferase expression was statistically associated with late hepatoblastoma diagnosis, a known clinical variable of worse prognosis. In addition, untargeted metabolomics analysis detected aberrant lipid metabolism in hepatoblastomas. Data presented here showed the first evidence that nicotinamide N-methyltransferase reduction occurs in hepatoblastomas, providing further support that the nicotinamide N-methyltransferase downregulation is a wide phenomenon in liver cancer. Furthermore, this study unraveled the role of DNA methylation in the regulation of nicotinamide N-methyltransferase expression in hepatoblastomas, in addition to evaluate the potential effect of nicotinamide N-methyltransferase reduction in the metabolism of these tumors. These preliminary findings also suggested that nicotinamide N-methyltransferase level may be a potential prognostic biomarker for hepatoblastoma.

Hepatectomía central combinada con ligadura de la vena porta derecha en un niño con hepatoblastoma bilobar: reporte de un caso / Central hepatectomy combined with ligation of the right portal vein in a child with bilobar hepatobastoma: a case report

Resumen El hepatoblastoma es un tumor maligno, la resección quirúrgica es la meta del tratamiento. Paciente de 7 meses de edad con masa hepática en los segmentos IV A y B, V y VIII, clasificada como PRETEXT III, se realizó hepatectomía central conservando segmentos VI, VII, II, III y doble derivación biliodigestiva. La vena porta derecha involucrada, se ligó para producir hiperplasia compensadora izquierda, conservando el derecho como auxiliar. Hígado izquierdo en 14 días aumentó 48.1 %. Como alternativa al trasplante, en un tiempo quirúrgico se combinó hepatectomía central con ligadura de la vena porta derecha.

Abstract Hepatoblastoma is a malignant tumor. Surgical resection is the goal of treatment. A 7-month-old female patient with a hepatic mass in segments IV A and B, V, and VIII, classified as PRETEXT III. A central hepatectomy preserving segments VI, VII, II, and III, and a double biliodigestive derivation were performed. The right portal vein involved was ligated to produce a compensatory hyperplasia of the left liver, retaining the right one as an auxiliary. At 14 days, the left liver had increased by 48.1%. As an alternative to transplantation, central hepatectomy was combined with ligation of the right portal vein in a single surgical time.

Tumores hepáticos en edad pediátrica / Hepatic tumors in pediatric ages

Introducción: Los tumores del hígado representan de 1-2 por ciento de todas las neoplasias malignas de la infancia y de 15-20 por ciento de los tumores abdominales. Objetivo: Caracterizar desde el punto de vista clínico-quirúrgico a pacientes pediátricos con diagnóstico de tumor hepático. Métodos: Estudio descriptivo y transversal realizado en el hospital pediátrico Juan Manuel Márquez. Se revisaron historias clínicas, informes histopatológicos e informes operatorios en el periodo comprendido entre el 1ro. de enero de 1997 al 31 de diciembre de 2017, para obtener los datos clínicos necesarios para la investigación. La muestra quedó conformada por 63 pacientes. Se emplearon frecuencias absolutas y porcentajes para variables cualitativas. Para las variables cuantitativas, se emplearon además medidas de tendencia central y de dispersión. Resultados: Se constató que 33 (52,4 por ciento) pacientes fueron del sexo masculino. El mayor número de enfermos se concentró en el grupo de 1 a 5 años con 36 (57,1 por ciento). El tumor más frecuente fue el hepatoblastoma y dentro de este el hepatoblastoma fetal, del cual se registraron 16 pacientes (25,4 por ciento). En 34 pacientes (54 por ciento) se combinó el tratamiento médico y el quirúrgico. Conclusiones: Predominan los pacientes masculinos, entre 1 y 5 años de edad. Se identifican principalmente tumores hepáticos epiteliales, malignos en estadio III y la variedad histológica de hepatoblastoma fetal. El tratamiento más utilizado es el médico-quirúrgico según protocolo del hospital dependiente del tipo histológico(AU)

Introduction: Liver tumors represent 1-2 percent of all the malignant neoplasms in children and the 15-20 percent of abdominal tumors. Objective: To characterize from the clinical surgical perspective the pediatric patients with a diagnosis of hepatic tumor. Methods: Descriptive and cross-sectional study conducted in Juan Manuel Márquez Pediatric Hospital. There were reviewed clinical records, histopathological reports and surgical reports from January 1st, 1997 to December 31st, 2017, to obtain necessary clinical data for the research. The sample was formed by 63 patients. There were used absolute frequencies and percentages for qualitative variables. For quantitative variables, there were used central trend and diffusion measures. Results: It was verified that 33 patients (52.4 percent) were males. The biggest number of patients was in the age group from 1 to 5 years being 36 (57.1 percent). The most frequent tumor was the hepatoblastoma and within this category the fetal hepatoblastoma, with 16 (25.4 percent) patients with that condition. In 34 patients (54 percent) were combined medical and surgical approchaes. Conclusions: There was a predominance of male patients in the ages from 1 to 5 years. There were mainly identified patients with epitelial hepatic tumors, malignant tumors in stage III and the histopatological variation of fetal hepatoblastoma. The most common treatment was the medical-surgical one according to the hospital´s protocols and depending on the histologic type(AU)

Childhood liver tumors in Argentina: Incidence trend and survival by treatment center. A report from the national pediatric cancer registry, ROHA network 2000-2015.

BACKGROUND: Information on the epidemiology of pediatric liver tumors in Latin America is limited. PURPOSE: To describe the incidence of liver tumors in a pediatric registry in Argentina according to geographic region, national trends over 16 years, and survival related to stage, age, sex, and care center. METHODS: Newly diagnosed liver tumors cases are registered in the Argentine Pediatric Oncology Hospital Registry (ROHA) with an estimated coverage of 91% of national cases. Age-standardized incidence rate per millon (ASR) was calculated based on the National Vital Statistics Reports. Five-year overall survival (OS) was estimated using the Kaplan-Meier method. The log-rank test was used to compare subgroup survival. RESULTS: Two hundred seven cases of hepatoblastoma (HB) and 73 of hepatocellular carcinoma (HCC) were identified. ASR of liver tumors was 1.8/million (95% confidence Interval [CI], 1.6-2.0) per year. ASR was 1.4 (1.2-1.6) for HB and 0.4 (0.3-0.5) for HCC. For HB, the highest incidence was found in the northwest region including the Altiplano. OS was 60.4% (53.4-66.8) for HB and 36.1% (25.2-47.2) for HCC. Five-year survival rate of children with metastatic HB treated at liver transplant hospitals (LTH) was 54.2% (30.3-73.0) compared to 13.3% (2.2-34.6) for those seen at other hospitals (OH) (P = .02), while for HCC this rate was 46.3% (30.7-60.6) at LTH compared to 17.5% (3.1-41.9) at OH (P = .01). CONCLUSIONS: The incidence rate of pediatric liver tumors was stable over the 16-year study period. Patients may benefit if at treatment initiation they are evaluated jointly with LTH specialists to define treatment strategies.

Hepatoblastoma del adulto: presentación de un caso / A case of adult hepatoblastoma

Resumen Fundamento: el hepatoblastoma del adulto (HBA) es un tumor hepático poco frecuente y con un mal pronóstico, lo cual contrasta con el hepatoblastoma infantil (HBI). Esta patología aún no ha sido comprendida completamente y hasta la fecha, no se han reportado de forma adecuada más de 50 casos en la literatura médica. Objetivo: presentar el caso de un paciente que fue egresado de nuestro hospital con el diagnóstico de carcinoma hepatocelular, aproximadamente con 3 meses de anterioridad. Caso clínico: paciente masculino de 60 años con historia de alcoholismo y de ser un fumador inveterado. Fue ingresado en nuestro hospital por dolor abdominal, en el momento del examen físico, puso de manifiesto un tumor palpable en la región del hipocondrio derecho. Este paciente había sido egresado aproximadamente 3 meses atrás, con el diagnóstico de carcinoma hepatocelular, en el curso de una cirrosis hepática. El hombre falleció por causa de la progresión de la enfermedad y la autopsia reveló la existencia de un HBA. Conclusiones : el HBA es un tumor infrecuente, de grave pronóstico y muchos casos son asintomáticos hasta el momento del diagnóstico. Dicho tumor, por lo regular, presenta un gran tamaño. Las enzimas hepáticas, la alfafetoproteína y los estudios imagenológicos revelan el diagnóstico de un hepatocarcinoma, el cual es un tumor frecuente en los adultos. Asimismo, el estudio histológico confirma el diagnóstico. Debido a su mal pronóstico, y a las mejores perspectivas de tratamiento en niños, hoy en día es lógico utilizar el tratamiento pediátrico en los adultos. Se necesitan más estudios de investigación para el manejo óptimo del HBA.

Abstract Background: In contrast to childhood hepatoblastoma, adult hepatoblastoma (HBA) is a rare and not-fully-understood liver tumor with a poor prognosis. To date, about 50 cases have been adequately reported in the medical literature. Objective: We present the case of a patient who was discharged from our hospital with a diagnosis of hepatocellular carcinoma approximately 3 months before returning. Clinical case: A 60-year-old male patient with a history of alcoholism and heavy smoking was admitted to our hospital for abdominal pain. Physical examination revealed a palpable tumor in the right hypochondrium region. This patient had been discharged approximately 3 months previously with a diagnosis of hepatocellular carcinoma in the course of liver cirrhosis. The patient died, and the autopsy revealed an HBA. Conclusions: Adult hepatoblastoma is an infrequent tumor with a severe prognosis. Many cases are asymptomatic until the time of diagnosis, and the tumor is usually very large. Liver enzymes, alpha-fetus protein, and imaging studies lead to a diagnosis of hepatocellular carcinoma which is a common tumor in adults. Histological study confirms the diagnosis. Due to the poor prognosis for HBA in contrast to better prospects for treatment of hepatoblastoma in children, it is logical to use pediatric treatment in adults. More research is needed for the optimal treatment of HBA.

Insights Into the Somatic Mutation Burden of Hepatoblastomas From Brazilian Patients.

Hepatoblastoma is a very rare embryonal liver cancer supposed to arise from the impairment of hepatocyte differentiation during embryogenesis. In this study, we investigated by exome sequencing the burden of somatic mutations in a cohort of 10 hepatoblastomas, including a congenital case. Our data disclosed a low mutational background and pointed out to a novel set of candidate genes for hepatoblastoma biology, which were shown to impact gene expression levels. Only three recurrently mutated genes were detected: CTNNB1 and two novel candidates, CX3CL1 and CEP164. A relevant finding was the identification of a recurrent mutation (A235G) in two hepatoblastomas at the CX3CL1 gene; evaluation of RNA and protein expression revealed upregulation of CX3CL1 in tumors. The analysis was replicated in two independents cohorts, substantiating that an activation of the CX3CL1/CX3CR1 pathway occurs in hepatoblastomas. In inflammatory regions of hepatoblastomas, CX3CL1/CX3CR1 were not detected in the infiltrated lymphocytes, in which they should be expressed in normal conditions, whereas necrotic regions exhibited negative labeling in tumor cells, but strongly positive infiltrated lymphocytes. Altogether, these data suggested that CX3CL1/CX3CR1 upregulation may be a common feature of hepatoblastomas, potentially related to chemotherapy response and progression. In addition, three mutational signatures were identified in hepatoblastomas, two of them with predominance of either the COSMIC signatures 1 and 6, found in all cancer types, or the COSMIC signature 29, mostly related to tobacco chewing habit; a third novel mutational signature presented an unspecific pattern with an increase of C>A mutations. Overall, we present here novel candidate genes for hepatoblastoma, with evidence that CX3CL1/CX3CR1 chemokine signaling pathway is likely involved with progression, besides reporting specific mutational signatures.