Hepatoblastoma associated with Beckwith-Wiedemann syndrome and hemihypertrophy

A rare case of extremely low birth weight infant with Beckwith-Wiedemann syndrome

INTRODUCTION

Beckwith-Wiedemann syndrome (BWS) manifests distinctive features, such as macroglossia, overgrowth, and abdominal wall defects. In this report, we describe a case of BWS in an extremely low birth weight infant diagnosed at three months after birth because of the intensive care for low birth weight.

PRESENTATION OF CASE

A female infant was delivered at 24 weeks and 6 days of gestation with a weight of 845 g. After birth, significant small intestinal intra-umbilical prolapse was observed, and abdominal wall closure using a sutureless method was performed on day zero. Careful neonatal management was performed; however, an episode of bloody stools led to a diagnosis of intestinal volvulus due to intestinal malrotation. At 119 days of age, the Ladd procedure was performed. Notably, during anaesthesia induction, features suggestive of BWS were observed, leading to its diagnosis.

DISCUSSION

Early diagnosis of BWS is vital because of its association with tumors. However, because she was an extremely low birth weight infant who required oral intubation and supine management for respiratory control, nevus flammeus and macroglossia were not observed. Therefore, BWS was not diagnosed for approximately three months after birth. It is important to recognize that omphalocele in extremely low birth weight infants is a risk factor for delayed diagnosis of BWS.

CONCLUSION

Timely diagnosis of BWS is critical because of its association with tumors and varied clinical presentations. Early screening, especially for tumors, and awareness among surgical practitioners can aid in timely interventions and improved patient outcomes.

The Genetic Changes of Hepatoblastoma

Hepatoblastoma is the most common malignant liver cancer in childhood. The etiology of hepatoblastoma remains obscure. Hepatoblastoma is closely related to genetic syndromes, hinting that hepatoblastoma is a genetic predisposition disease. However, no precise exposures or genetic events are reported to hepatoblastoma occurrence. During the past decade, significant advances have been made in the understanding of etiology leading to hepatoblastoma, and several important genetic events that appear to be important for the development and progression of this tumor have been identified. Advances in our understanding of the genetic changes that underlie hepatoblastoma may translate into better patient outcomes. Single nucleotide polymorphisms (SNPs) have been generally applied in the research of etiology's exploration, disease treatment, and prognosis assessment. Here, we reviewed and discussed the molecular epidemiology, especially SNPs progresses in hepatoblastoma, to provide references for future studies and promote the study of hepatoblastoma's etiology.

Pediatric Cushing syndrome: An early sign of an underling cancer predisposition syndrome

Beckwith-Wiedemann syndrome (BWS) is a genetic overgrowth and cancer predisposition syndrome that can be associated with a spectrum of clinical features including isolated lateralized overgrowth, macrosomia, macroglossia, organomegaly, omphalocele/umbilical hernia, and distinct facial features. Because of a range of clinical presentations and molecular defects involving Chromosome 11p15, many cases will fall within what is now being defined as the Beckwith-Wiedemann spectrum (BWSp). Cushing syndrome (CS) in infants is a rare neuroendocrinological disease associated with hypercortisolism that has rarely been reported in patients with BWS. Here, we describe the first case of a 5-month-old male with CS secondary to paternal uniparental disomy of Chromosome 11p without additional clinical signs or symptoms of BWS. This case continues to expand the phenotypic spectrum of BWSp.

Exosomal MiRNAs in Pediatric Cancers

MicroRNAs (miRNAs) have generated great attention in oncology as they play a fundamental role in the regulation of gene expression and their aberrant expression is present in almost all types of tumors including pediatric ones. The discovery that miRNAs can be transported by exosomes, which are vesicles of 40–120 nm involved in cellular communication, that are produced by different cell types, and that are present in different biological fluids, has opened the possibility of using exosomal miRNAs as biomarkers. The possibility to diagnose and monitor the progression and response to drugs through molecules that can be easily isolated from biological fluids represents a particularly important aspect in the pediatric context where invasive techniques are often used. In recent years, the idea of liquid biopsy as well as studies on the possible role of exosomal miRNAs as biomarkers have developed greatly. In this review, we report an overview of all the evidences acquired in recent years on the identification of exosomal microRNAs with biomarker potential in pediatric cancers. We discuss the following herein: neuroblastoma, hepatoblastoma, sarcomas (osteosarcoma, Ewing’s sarcoma and rhabdoid tumors, and non-rhabdomyosarcoma soft tissue sarcoma), brain tumors, lymphomas, and leukemias.

Coordinated Activities of Multiple Myc-dependent and Myc-independent Biosynthetic Pathways in Hepatoblastoma

Hepatoblastoma (HB) is associated with aberrant activation of the β-catenin and Hippo/YAP signaling pathways. Overexpression of mutant β-catenin and YAP in mice induces HBs that express high levels of c-Myc (Myc). In light of recent observations that Myc is unnecessary for long-term hepatocyte proliferation, we have now examined its role in HB pathogenesis using the above model. Although Myc was found to be dispensable for in vivo HB initiation, it was necessary to sustain rapid tumor growth. Gene expression profiling identified key molecular differences between myc^+/+ (WT) and myc^-/- (KO) hepatocytes and HBs that explain these behaviors. In HBs, these included both Myc-dependent and Myc-independent increases in families of transcripts encoding ribosomal proteins, non-structural factors affecting ribosome assembly and function, and enzymes catalyzing glycolysis and lipid bio-synthesis. In contrast, transcripts encoding enzymes involved in fatty acid β-oxidation were mostly down-regulated. Myc-independent metabolic changes associated with HBs included dramatic reductions in mitochondrial mass and oxidative function, increases in ATP content and pyruvate dehydrogenase activity, and marked inhibition of fatty acid β-oxidation (FAO). Myc-dependent metabolic changes included higher levels of neutral lipid and acetyl-CoA in WT tumors. The latter correlated with higher histone H3 acetylation. Collectively, our results indicate that the role of Myc in HB pathogenesis is to impose mutually dependent changes in gene expression and metabolic reprogramming that are unattainable in non-transformed cells and that cooperate to maximize tumor growth.

Patient-derived mouse xenografts from pediatric liver cancer predict tumor recurrence and advise clinical management

Identification of new treatments for relapsing pediatric cancer is an unmet clinical need and a societal challenge. Liver cancer occurrence in infancy, 1.5 for million children per year, falls far below the threshold of interest for dedicated drug development programs, and this disease is so rare that it is very difficult to gather enough children into a phase II clinical trial. Here, we present the establishment of an unprecedented preclinical platform of 24 pediatric liver cancer patient-derived xenografts (PLC-PDXs) from 20 hepatoblastomas (HBs), 1 transitional liver cell tumor (TCLT), 1 hepatocellular carcinoma, and 2 malignant rhabdoid tumors. Cytogenetic array and mutational analysis of the parental tumors and the corresponding PLC-PDXs show high conservation of the molecular features of the parental tumors. The histology of PLC-PDXs is strikingly similar to that observed in primary tumors and recapitulates the heterogeneity of recurrent disease observed in the clinic. Tumor growth in the mouse is strongly associated with elevated circulating alpha-fetoprotein (AFP), low rate of necrosis/fibrosis after treatment, and gain of chromosome 20, all indicators of resistance to chemotherapy and poor outcome. Accordingly, the ability of a tumor to generate PLC-PDX is predictive of poor prognosis. Exposure of PLC-PDXs to standards of care or therapeutic options already in use for other pediatric malignancies revealed unique response profiles in these models. Among these, the irinotecan/temozolomide combination induced strong tumor regression in the TCLT and in a model derived from an AFP-negative relapsing HB.

CONCLUSION

These results provide evidence that PLC-PDX preclinical platform can strongly contribute to accelerate the identification and diversification of anticancer treatment for aggressive subtypes of pediatric liver cancer. (Hepatology 2016;64:1121-1135).

α-Fetoprotein assay on dried blood spot for hepatoblastoma screening in children with overgrowth-cancer predisposition syndromes

BACKGROUND

Beckwith-Wiedemann syndrome (BWS) and hemihyperplasia (HH) are overgrowth conditions with predisposition to hepatoblastoma for which early diagnosis patients undergo cancer screening based on determination of the tumor marker α-fetoprotein (αFP). Repeated blood draws are a burden for patients with consequent compliance issues and poor adherence to surveillance protocol. We sought to analyze feasibility and reliability of αFP dosage using an analytical micromethod based on blood dried on filter paper (DBS).

METHODS

Overall 143 coupled αFP determinations on plasma and DBS collected simultaneously were performed, of which 31 were in patients with hepatoblastoma predisposition syndromes and 112 were in controls. The plasma αFP dosage method was adapted to DBS adsorbed on paper matrix for newborn screening.

RESULTS

There was strong correlation between plasmatic and DBS αFP (r2 = 0.999, P < 0.001). Cohen's k coefficient for correlation was 0.96 for diagnostic cut-off of 10 U/ml (P < 0.001), commonly employed in clinical practice. The measurements on plasma and DBS were highly overlapping and consistent.

CONCLUSION

The DBS method allowed to dose αFP reliably and consistently for the concentrations commonly employed in clinical settings for the screening of hepatoblastoma, opening new scenarios about conducting cancer screening in overgrowth syndromes.

Hepatoblastoma in association with bilateral polycystic kidneys

We describe the first known case of hepatoblastoma associated with bilateral autosomal recessive polycystic kidney disease in a preterm twin boy. The diagnostic and therapeutic considerations are addressed. The patient survived after primary hepatectomy operation and administration of modified adjuvant chemotherapy.

Establishment and characterization of a cancer cell line derived from an aggressive childhood liver tumor

BACKGROUND

Hepatoblastoma is a rare malignancy of childhood. The scarcity of adequate cell models has limited our understanding of this tumor. Here we describe and characterize a new human liver tumor cell line, Hep293TT, derived from an aggressive childhood hepatoblastoma.

PROCEDURES

Hep293TT cells were established using primary tumor tissues from a 5-year-old Caucasian female child. This cell line has been maintained for more than 34 months and over 20 subcultures, and was characterized by histopathology, ELISA, genotype, cytogenetics, CGH array, immunohistochemistry, and molecular sequence analyses.

RESULTS

Cells were confirmed to originate from parental tumor cells, secrete alpha-fetoprotein, and express hepatic markers and beta-catenin. Hep293TT cells were able to form colonies in soft agar. Tumorigenicity was demonstrated by induction of solid tumors after subrenal capsule injection in immunodeficient mice. Hep293TT cells demonstrated a highly aneuploid karyotype, and a whole genome CGH analysis revealed chromosomal imbalances in every chromosome. Allelotype analysis demonstrated loss of alleles at distal 11p15.5 as is typical of embryonal tumors. Both Hep293TT cells and the primary tumor contain a deletion of 351 nucleotides in beta-catenin, as has been seen in other hepatoblastoma tumors. The cell line expressed beta-catenin protein in both full-length and partially deleted forms, and expressed NOTCH2 protein characteristic of hepatoblasts. No mutation was detected in the APC, MYH, MLH1, or MSH2 genes.

CONCLUSION

This cell line, Hep293TT, is a valuable resource for the study of childhood liver cancer and may potentially provide a tool in the development of new agents.

Focal nodular hyperplasia of the liver and elevated alpha fetoprotein level in an infant with isolated hemihyperplasia

A case of focal nodular hyperplasia of the liver in a 43-day-old baby girl with isolated hemihyperplasia and elevated serum alpha-fetoprotein is presented. The child referred to our hospital with bilateral renal masses detected by prenatal and postnatal ultrasonography. A mass lesion was detected in segment 6 of liver and was diagnosed as focal nodular hyperplasia. We present this case to emphasize the presence of focal nodular hyperplasia in a patient with isolated hemihypertrophy and elevated serum alpha-fetoprotein level.

Acinar cell carcinoma versus solid pseudopapillary tumor of the pancreas in children: a comparison of two rare and overlapping entities with review of the literature

Primary epithelial tumors of the pancreas are extremely uncommon in children, and among these, acinar cell carcinoma (ACC) is the most rare. Here we describe our recent observations in the case of a 10-year-old boy with one of these exceptional examples. The histologic diagnosis of ACC was supported by both immunohistochemistry and electron microscopy. Despite its rarity, ACC should be kept in the differential diagnosis of pediatric pancreatic exocrine tumors. We also provide a comparison with an example of solid pseudopapillary tumor, another relatively infrequent epithelial tumor of the pancreas in the young. We review the relevant literature addressing the clinical and pathologic features of ACC and its distinction from other pancreatic neoplasms.

Sporadic childhood hepatoblastomas show activation of beta-catenin, mismatch repair defects and p53 mutations

Hepatoblastoma, a rare embryonic tumor that may arise sporadically or in the context of hereditary syndromes (familial adenomatous polyposis and Beckwith-Wiedemann's) is the most frequent liver cancer of childhood. Deregulation of the APC/beta-catenin pathway occurs in a consistent fraction of hepatoblastomas, with mutations in the APC and beta-catenin genes implicated in familial adenomatous polyposis-associated and sporadic hepatoblastomas, respectively. Alterations in other cancer-related molecular pathways have not been reported. We investigated a series of 21 sporadic paraffin-embedded hepatoblastoma cases for mutations in the p53 (exons 5-8) and beta-catenin (exon 3) genes, loss of heterozygosity at APC, microsatellite instability and immunohistochemical expression of beta-catenin and of the two main mismatch repair proteins, MLH1 and MSH2. No loss of heterozygosity at APC was detected. We found mutations in beta-catenin and p53 in 4/21 (19%) and 5/21 (24%) cases respectively, beta-catenin protein accumulation in 14/21 cases (67%), microsatellite instability in 17/21 cases (81%), of which eight resulted positive for high-level of microsatellite instability (in four cases associated with loss of MLH1/MSH2 immunostaining). No correlations between involved molecular pathway(s) and hepatoblastoma histotype(s) emerged. This study confirms that beta-catenin deregulation is involved in sporadic hepatoblastoma and also suggests that mismatch repair defects and p53 mutations contribute to this rare liver cancer. Sporadic hepatoblastoma appears to be molecularly and phenotypically heterogeneous and may reflect different pathways of liver carcinogenesis.

Hepatoblastoma and heart transplantation in a patient with cardio-facio-cutaneous syndrome

Cardio-facio-cutaneous syndrome (CFC) and Costello syndrome (CS) are disorders with an overlapping spectrum of congenital anomalies. Mutations in the RAS-MAPK pathway have recently been reported in both of these syndromes, with HRAS mutations characteristic for CS and BRAF and MEK1/2 mutations for CFC. We report on a 3-year-old boy who underwent a cardiac transplant at age 8 months for hypertrophic cardiomyopathy; he was subsequently suspected to have CS. At age 35 months he presented with an intra-cardiac mass that was diagnosed as metastatic hepatoblastoma. Although hepatoblastoma is not known to have an increased frequency in immunocompromised patients, questions were raised as whether the post-transplant immuno-suppressive therapy played a role in tumor development. The patient died shortly thereafter and his post-mortem DNA analysis revealed a MEK1 mutation (Y130C) previously reported in CFC. While CS is associated with increased cancer risk, only a single case of leukemia has been reported in a patient with CFC, making this the first case of a solid tumor reported in a patient with CFC.

Risk of tumorigenesis in overgrowth syndromes: a comprehensive review

Overgrowth syndromes (OGS) comprise a heterogeneous group of disorders in which the main characteristic is that either weight, height, or head circumference is 2-3 standard deviations (SD) above the mean for sex and age. A striking feature of OGS is the risk of neoplasms. Here, the relative frequency of specific tumors in each OGS, topographic location, and age of appearance is determined by reviewing published cases. In some OGS (Perlman, Beckwith-Wiedemann, and Simpson-Golabi-Behmel syndromes and hemihyperplasia) more than 94% of tumors appeared in the abdomen usually before 10 years of age, mainly embryonal in type. In Perlman syndrome, only Wilms tumor has been recorded, whereas in Sotos syndrome, lympho-hematologic tumors are most frequent. Based on literature review, a specific schedule protocol for tumor screening is suggested for each OGS. A schedule with different intervals and specific tests is proposed for a more rational cost/benefit program for these disorders.

Congenital hemihypertrophy with hemihypertrichosis

The rare condition in which one side of the body seems to grow faster than the other is called hemihypertrophy. This may be accepted as normal, but there are certain serious conditions that may be associated with this type of growth pattern. Congenital hypertrichosis is believed to be a genetic disorder that is inherited or occurs as a result of spontaneous mutation. The incidence of generalised congenital hypertrichosis is about one in a billion. A seven-month-old female case was brought to the hospital with growth and hairiness complaints, which were more apparent in the right side of the face, the right arm and the right leg. Physical examination showed more apparent hypertrophy and hypertrichosis, which covered the entire right side of the body beginning from the face and including the lower extremities and the genitalia. Hypertrichosis was more evident above the right scapula and on the right leg. The diameter of the right upper extremity and the right lower extremity were measured at 13 mm and 14 mm thicker than the left side, respectively. The infant did not have teeth yet and had totally normal nail growth. Skeletal structure, cardiovascular, respiratory, urogenital, central nervous system and eye examinations were all normal. Results of all laboratory analyses, including genetic examination, and those of the imaging techniques were found to be normal. We hereby present the rare co-presence of hemihypertrophy and hemihypertrichosis, for which we could not identify an etiological cause and which is the third such case in the literature.

Prenatal diagnosis of Beckwith-Wiedemann syndrome

OBJECTIVES

The diagnosis of Beckwith-Wiedemann syndrome (BWS) typically is made after birth. To our knowledge, no established guidelines exist for the prenatal diagnosis of this condition. We present two new cases of prenatally diagnosed BWS and propose a diagnostic schema.

METHODS

Published reports obtained from Medline searches were reviewed and combined with our cases.

RESULTS

Our proposed schema of two major criteria (abdominal wall defect, macroglossia, macrosomia) or one major plus two minor criteria (nephromegaly/dysgenesis, adrenal cytomegaly, aneuploidy/abnormal loci, polyhydramnios) fits all published reports of prenatally diagnosed BWS.

CONCLUSION

The prenatal diagnosis of BWS can be reliably made by applying our proposed guidelines. This schema allows for uniform fetal diagnosis of the syndrome and helps prepare for prenatal counseling and peri- and post-natal management strategies.

The neonate with an abdominal mass

Abdominal masses in neonates reflect a wide spectrum of diseases,from lesions that can cause significant morbidity and mortality,to conditions readily corrected surgically, to entities which maybe safely observed. It is incumbent upon the infant's physician to determine the nature of the mass in a timely, safe, and cost-effective manner.