Germline CBL mutation associated with a noonan-like syndrome with primary lymphedema and teratoma associated with acquired uniparental isodisomy of chromosome 11q23

A case series and literature review on 98 pediatric patients of germ cell tumor developing growing teratoma syndrome

INTRODUCTION

Malignant germ cell tumors (MGCTs) can develop either extracranially or intracranially. Growing teratoma syndrome (GTS) may develop in these patients following chemotherapy. Reports on the clinical characteristics and outcomes of GTS in children with MGCTs are limited.

METHODS

We retrospectively collected the data, including the clinical characteristics and outcomes of five patients in our series and 93 pediatric patients selected through a literature review of MGCTs. This study aimed to analyze survival outcomes and risk factors for subsequent events in pediatric patients with MGCTs developing GTS.

RESULTS

The sex ratio was 1.09 (male/female). In total, 52 patients (53.1%) had intracranial MGCTs. Compared with patients with extracranial GCTs, those with intracranial GCTs were younger, predominantly boys, had shorter intervals between MGCT and GTS, and had GTS mostly occurring over the initial site (all p < 0.001). Ninety-five patients (96.9%) were alive. However, GTS recurrence (n = 14), GTS progression (n = 9), and MGCT recurrence (n = 19) caused a substantial decrease in event-free survival (EFS). Multivariate analyses showed that the only significant risk factors for these events were incomplete GTS resection and different locations of GCT and GTS. Patients without any risk had a 5-year EFS of 78.8% ± 7.8%, whereas those with either risk had 41.7% ± 10.2% (p < 0.001).

CONCLUSION

For patients with high-risk features, every effort should be made to closely monitor, completely remove, and pathologically prove any newly developed mass to guide relevant treatment. Further studies incorporating the risk factors into treatment strategies may be required to optimize adjuvant therapy.

Pathological MAPK activation-mediated lymphatic basement membrane disruption causes lymphangiectasia that is treatable with ravoxertinib

Lymphangiectasia, an anomalous dilation of lymphatic vessels first described in the 17th century, is frequently associated with chylous effusion, respiratory failure, and high mortality in young patients, yet the underlying molecular pathogenesis and effective treatments remain elusive. Here, we identify an unexpected causal link between MAPK activation and defective development of the lymphatic basement membrane that drives lymphangiectasia. Human pathological tissue samples from patients diagnosed with lymphangiectasia revealed sustained MAPK activation within lymphatic endothelial cells. Endothelial KRASG12D-mediated sustained MAPK activation in newborn mice caused severe pulmonary and intercostal lymphangiectasia, accumulation of chyle in the pleural space, and complete lethality. Pathological activation of MAPK in murine vasculature inhibited the Nfatc1-dependent genetic program required for laminin interactions, collagen crosslinking, and anchoring fibril formation, driving defective development of the lymphatic basement membrane. Treatment with ravoxertinib, a pharmacological inhibitor of MAPK, reverses nuclear-to-cytoplasmic localization of Nfatc1, basement membrane development defects, lymphangiectasia, and chyle accumulation, ultimately improving survival of endothelial KRAS mutant neonatal mice. These results reveal defective lymphatic basement membrane assembly and composition as major causes of thoracic lymphangiectasia and provide a potential treatment.

Patients with Chromosome 11q Deletions Are Characterized by Inborn Errors of Immunity Involving both B and T Lymphocytes

Disorders of the long arm of chromosome 11 (11q) are rare and involve various chromosomal regions. Patients with 11q disorders, including Jacobsen syndrome, often present with a susceptibility for bacterial and prolonged viral and fungal infections partially explained by hypogammaglobulinemia. Additional T lymphocyte or granular neutrophil dysfunction may also be present. In order to evaluate infectious burden and immunological function in patients with 11q disorders, we studied a cohort of 14 patients with 11q deletions and duplications. Clinically, 12 patients exhibited prolonged and repetitive respiratory tract infections, frequently requiring (prophylactic) antibiotic treatment (n = 7), ear-tube placement (n = 9), or use of inhalers (n = 5). Complicated varicella infections (n = 5), chronic eczema (n = 6), warts (n = 2), and chronic fungal infections (n = 4) were reported. Six patients were on immunoglobulin replacement therapy. We observed a high prevalence of low B lymphocyte counts (n = 8), decreased T lymphocyte counts (n = 5) and abnormal T lymphocyte function (n = 12). Granulocyte function was abnormal in 29% without a clinical phenotype. Immunodeficiency was found in patients with terminal and interstitial 11q deletions and in one patient with terminal 11q duplication. Genetically, FLI1 and ETS1 are seen as causative for the immunodeficiency, but these genes were deleted nor duplicated in 4 of our 14 patients. Alternative candidate genes on 11q may have a role in immune dysregulation. In conclusion, we present evidence that inborn errors of immunity are present in patients with 11q disorders leading to clinically relevant infections. Therefore, broad immunological screening and necessary treatment is of importance in this patient group.

Role of CBL Mutations in Cancer and Non-Malignant Phenotype

Simple Summary

CBL mutations are progressively being described as involved in different clinical manifestations. Somatic CBL mutations can be found in different type of cancer. The clinical spectrum of germline mutations configures the so-called CBL syndrome, a cancer-predisposing condition that includes multisystemic involvement characterized by variable phenotypic expression and expressivity. In this review we provide an up-to-date review of the clinical manifestation of CBL mutations and of the molecular mechanisms in which CBL exerts its pathogenic role.

Abstract

CBL plays a key role in different cell pathways, mainly related to cancer onset and progression, hematopoietic development and T cell receptor regulation. Somatic CBL mutations have been reported in a variety of malignancies, ranging from acute myeloid leukemia to lung cancer. Growing evidence have defined the clinical spectrum of germline CBL mutations configuring the so-called CBL syndrome; a cancer-predisposing condition that also includes multisystemic involvement characterized by variable phenotypic expression and expressivity. This review provides a comprehensive overview of the molecular mechanisms in which CBL exerts its function and describes the clinical manifestation of CBL mutations in humans.

Lymphatic Abnormalities in Noonan Syndrome Spectrum Disorders: A Systematic Review

Noonan syndrome spectrum disorders are a group of phenotypically related conditions, resembling Noonan syndrome, caused by germline pathogenic variants in genes within the Ras/mitogen-activated protein kinase (Ras/MAPK) signalling pathway. Lymphatic dysplasia with a clinical lymphatic abnormality is one of the major features. We performed a systematic review to get more insight in (1) the prevalence of clinically lymphatic abnormalities in patients with a genetically proven Noonan syndrome spectrum disorder, (2) if a genotype-lymphatic phenotype relation can be found and describe the clinical presentation and course of the lymphatic abnormality. Most studies report patients with Noonan syndrome. Prenatally, the prevalence of increased nuchal translucency differs from 7% in patients with pathogenic PTPN11 variants to 38% in patients with pathogenic RIT1 variants, and the prevalence of pleural effusions differed from 7% in patients with pathogenic SOS1 to 29% in patients with pathogenic RIT1 variants. Postnatally, the prevalence of lymphedema differs from 16% in patients with pathogenic PTPN11 variants to 44% in patients with pathogenic SOS1 variants, and the prevalence of acquired chylothorax is 4% in patients with pathogenic RIT1 variants. Lymphatic abnormalities do occur in patients with cardiofaciocutaneous syndrome and Costello syndrome. In conclusion, Noonan syndrome spectrum disorders, Noonan syndrome in particular, are associated with lymphatic abnormalities. Combining the available published literature about genetically proven Noonan syndrome spectrum disorders, it appears likely that the lifetime prevalence of these abnormalities in Noonan syndrome is higher than the 20% that were generally accepted so far. This is increasingly important, because the activation of the RAS/MAPK pathway can be inhibited by RAS/MAPK inhibitors, and clinically severe lymphatic abnormalities may improve.

Inside the Noonan "universe": Literature review on growth, GH/IGF axis and rhGH treatment: Facts and concerns

Noonan syndrome (NS) is a disorder characterized by a typical facial gestalt, congenital heart defects, variable cognitive deficits, skeletal defects, and short stature. NS is caused by germline pathogenic variants in genes coding proteins with a role in the RAS/mitogen-activated protein kinase signaling pathway, and it is typically associated with substantial genetic and clinical complexity and variability. Short stature is a cardinal feature in NS, with evidence indicating that growth hormone (GH) deficiency, partial GH insensitivity, and altered response to insulin-like growth factor I (IGF-1) are contributing events for growth failure in these patients. Decreased IGF-I, together with low/normal responses to GH pharmacological provocation tests, indicating a variable presence of GH deficiency/resistance, in particular in subjects with pathogenic PTPN11 variants, are frequently reported. Nonetheless, short- and long-term studies have demonstrated a consistent and significant increase in height velocity (HV) in NS children and adolescents treated with recombinant human GH (rhGH). While the overall experience with rhGH treatment in NS patients with short stature is reassuring, it is difficult to systematically compare published data due to heterogeneous protocols, potential enrolment bias, the small size of cohorts in many studies, different cohort selection criteria and varying durations of therapy. Furthermore, in most studies, the genetic information is lacking. NS is associated with a higher risk of benign and malignant proliferative disorders and hypertrophic cardiomyopathy, and rhGH treatment may further increase risk in these patients, especially as dosages vary widely. Herein we provide an updated review of aspects related to growth, altered function of the GH/IGF axis and cell response to GH/IGF stimulation, rhGH treatment and its possible adverse events. Given the clinical variability and genetic heterogeneity of NS, treatment with rhGH should be personalized and a conservative approach with judicious surveillance is recommended. Depending on the genotype, an individualized follow-up and close monitoring during rhGH treatments, also focusing on screening for neoplasms, should be considered.

Primary lymphoedema

Lymphoedema is the swelling of one or several parts of the body owing to lymph accumulation in the extracellular space. It is often chronic, worsens if untreated, predisposes to infections and causes an important reduction in quality of life. Primary lymphoedema (PLE) is thought to result from abnormal development and/or functioning of the lymphatic system, can present in isolation or as part of a syndrome, and can be present at birth or develop later in life. Mutations in numerous genes involved in the initial formation of lymphatic vessels (including valves) as well as in the growth and expansion of the lymphatic system and associated pathways have been identified in syndromic and non-syndromic forms of PLE. Thus, the current hypothesis is that most cases of PLE have a genetic origin, although a causative mutation is identified in only about one-third of affected individuals. Diagnosis relies on clinical presentation, imaging of the structure and functionality of the lymphatics, and in genetic analyses. Management aims at reducing or preventing swelling by compression therapy (with manual drainage, exercise and compressive garments) and, in carefully selected cases, by various surgical techniques. Individuals with PLE often have a reduced quality of life owing to the psychosocial and lifelong management burden associated with their chronic condition. Improved understanding of the underlying genetic origins of PLE will translate into more accurate diagnosis and prognosis and personalized treatment.

Juvenile myelomonocytic leukemia in CBL syndrome associated with germline splice-site mutations: Two case reports and a literature review

The clinical and laboratory criteria for hemophagocytic lymphohistiocytosis should be taken into account during the juvenile myelomonocytic leukemia diagnosis, specifically in CBL syndrome, to reveal the presence of primary rather than secondary associated hemophagocytosis.

A Case of Uveitis in a Patient With Juvenile Myelomonocytic Leukemia Successfully Treated With Adalimumab

Patients with juvenile myelomonocytic leukemia due to germline CBL mutation (10% to 15%) may have a subacute course occasionally associated with autoimmune disorders, which may resemble RAS-associated autoimmune lymphoproliferative disorder. In both conditions, prognosis and standard treatment for autoimmune phenomena remain poorly understood. We report the case of a 7-year-old boy with juvenile myelomonocytic leukemia with severe steroid-dependent uveitis, who did not respond to several therapeutic attempts with immunosuppressant agents, including sirolimus, and was finally successfully treated with adalimumab. This case offers further insight into the management of autoimmune disorders in the context of predisposing genetic conditions.

Prioritization of genes involved in endothelial cell apoptosis by their implication in lymphedema using an analysis of associative gene networks with ANDSystem

BACKGROUND

Currently, more than 150 million people worldwide suffer from lymphedema. It is a chronic progressive disease characterized by high-protein edema of various parts of the body due to defects in lymphatic drainage. Molecular-genetic mechanisms of the disease are still poorly understood. Beginning of a clinical manifestation of primary lymphedema in middle age and the development of secondary lymphedema after treatment of breast cancer can be genetically determined. Disruption of endothelial cell apoptosis can be considered as one of the factors contributing to the development of lymphedema. However, a study of the relationship between genes associated with lymphedema and genes involved in endothelial apoptosis, in the associative gene network was not previously conducted.

METHODS

In the current work, we used well-known methods (ToppGene and Endeavour), as well as methods previously developed by us, to prioritize genes involved in endothelial apoptosis and to find potential participants of molecular-genetic mechanisms of lymphedema among them. Original methods of prioritization took into account the overrepresented Gene Ontology biological processes, the centrality of vertices in the associative gene network, describing the interactions of endothelial apoptosis genes with genes associated with lymphedema, and the association of the analyzed genes with diseases that are comorbid to lymphedema.

RESULTS

An assessment of the quality of prioritization was performed using criteria, which involved an analysis of the enrichment of the top-most priority genes by genes, which are known to have simultaneous interactions with lymphedema and endothelial cell apoptosis, as well as by genes differentially expressed in murine model of lymphedema. In particular, among genes involved in endothelial apoptosis, KDR, TNF, TEK, BMPR2, SERPINE1, IL10, CD40LG, CCL2, FASLG and ABL1 had the highest priority. The identified priority genes can be considered as candidates for genotyping in the studies involving the search for associations with lymphedema.

CONCLUSIONS

Analysis of interactions of these genes in the associative gene network of lymphedema can improve understanding of mechanisms of interaction between endothelial apoptosis and lymphangiogenesis, and shed light on the role of disturbance of these processes in the development of edema, chronic inflammation and connective tissue transformation during the progression of the disease.

Embryonal rhabdomyosarcoma in a patient with a germline CBL pathogenic variant

Germline pathogenic variants in CBL are associated with an autosomal dominant RASopathy and an increased risk for malignancies, particularly juvenile myelomonocytic leukemia. Herein, we describe a patient with clinical features of a Noonan-spectrum disorder who developed embryonal rhabdomyosarcoma of the bladder at age two years. Tumor analysis using the OncoKids^® cancer panel revealed a CBL pathogenic variant: NM_005188.3:c.1100A>C (p.Gln367Pro). Sanger sequencing of peripheral blood DNA confirmed a de novo heterozygous germline variant. This is the first report of embryonal rhabdomyosarcoma in association with a germline CBL pathogenic variant, further broadening the CBL cancer predisposition spectrum.

Genetic testing for lymphatic malformations with or without primary lymphedema

Lymphatic malformations (LMs) show phenotypic variability, as well as clinical and genetic heterogeneity. Inheritance is autosomal dominant, recessive or X-linked and major genes involved in predisposition for LMs are continuously being discovered. The literature also indicates that somatic mutations play an important role in the development of LMs. In fact, activating somatic mutations in PIK3CA have been reported in lymphatic endothelial cells obtained from patients with different kinds of LM. This Utility Gene Test was developed on the basis of an analysis of the literature and existing diagnostic protocols. It is useful for confirming diagnosis, as well as for differential diagnosis, couple risk assessment and access to clinical trials.

Genetic tests in lymphatic vascular malformations and lymphedema

Syndromes with lymphatic malformations show phenotypic variability within the same entity, clinical features that overlap between different conditions and allelic as well as locus heterogeneity. The aim of this review is to provide a comprehensive clinical genetic description of lymphatic malformations and the techniques used for their diagnosis, and to propose a flowchart for genetic testing. Literature and database searches were performed to find conditions characterised by lymphatic malformations or the predisposition to lymphedema after surgery, to identify the associated genes and to find the guidelines and genetic tests currently used for the molecular diagnosis of these disorders. This search allowed us to identify several syndromes with lymphatic malformations that are characterised by a great heterogeneity of phenotypes, alleles and loci, and a high frequency of sporadic cases, which may be associated with somatic mutations. For these disorders, we found many diagnostic tests, an absence of harmonic guidelines for molecular diagnosis and well-established clinical guidelines. Targeted sequencing is the preferred method for the molecular diagnosis of lymphatic malformations. These techniques are easy to implement and have a good diagnostic success rates. In addition, they are relatively inexpensive and permit parallel analysis of all known disease-associated genes. The targeted sequencing approach has improved the diagnostic process, giving patients access to better treatment and, potentially, to therapy personalised to their genetic profiles. These new techniques will also facilitate the prenatal and early postnatal diagnosis of congenital lymphatic conditions and the possibility of early intervention.

c-CBL regulates melanoma proliferation, migration, invasion and the FAK-SRC-GRB2 nexus

Melanoma is one of the most aggressive and lethal forms of skin cancer. Despite recent improvements in targeted therapies, many patients with advanced disease fail to achieve lasting tumor regression. Therefore, it is important to develop novel druggable targets that can be exploited to improve clinical outcome. Here, we studied the role of Casitas B-lineage lymphoma (c-CBL), an E3 ubiquitin ligase, in human melanoma. Employing quantitative real-time PCR and Western blot analysis in a panel of human melanoma cell lines (A375, G361, Hs-294T, SK-Mel-2, SK-Mel-28 and 451Lu), we found that c-CBL is strongly expressed in human melanoma cells at the mRNA and protein levels. Further, we determined c-CBL levels in clinical samples of melanomas and benign melanocytic nevi, using quantitative Nuance multispectral imaging. Compared to benign nevi, melanomas showed an overlapping range of c-CBL immunoreactivity. Small interfering RNA (siRNA)-mediated knockdown of c-CBL resulted in decreased proliferation, clonogenic survival and migration of melanoma cells. Furthermore, it also resulted in decreased cellular invasion in a 3D spheroid assay system. C-CBL and FAK are regulated by SRC, and FAK binds SRC and GRB2. C-CBL E3 ligase domain regulates receptor tyrosine kinase internalization through ubiquitination and its ring finger domain stabilizes the FAK-SRC-actin cytoskeleton thereby promoting cellular motility. C-CBL knockdown was associated with decreased protein and/or mRNA levels of SRC, FAK and GRB2. Taken together, we have provided evidence that c-CBL plays a role in melanoma cell proliferation, migration and invasion as well as inhibition of the FAK-GRB2-SRC nexus. Our findings indicate that additional studies are warranted to further dissect the role of c-CBL in melanoma and determine the therapeutic potential of its inhibition.

Paediatric ovarian tumours and their associated cancer susceptibility syndromes

Non-epithelial ovarian tumours are rare neoplasms that occasionally arise in childhood and adolescence. They can be associated with various cancer susceptibility syndromes. The morphological overlap seen across these tumours and their rarity can make the diagnosis challenging. In the case of an incorrect diagnosis, the underlying genetic susceptibility may be missed. In this review, we outline the genetic background of ovarian non-epithelial tumours arising in children, emphasizing the genes harbouring pathogenic germline variants associated with each tumour type. Specifically, juvenile granulosa cell tumours, Sertoli-Leydig cell tumours, sex cord tumours with annular tubules, Sertoli cell tumours, germ cell tumours and small cell carcinoma of the ovary of hypercalcaemic type are discussed in this review. For each tumour type, we detail the personal and family history features and the presenting characteristics of the ovarian tumour as well as the pathological features and molecular markers that point towards a cancer predisposition syndrome. Throughout, we stress the need for specialised pathological review in difficult cases.

A case of splenomegaly in CBL syndrome

INTRODUCTION

We present a child with unexplained splenomegaly to highlight this feature as a presenting sign of the RASopathy CBL syndrome and to draw attention to the power and utility of next generation genomic sequencing for providing rapid diagnosis and critical information to guide care in the pediatric clinical setting.

CLINICAL REPORT

A 7-year-old boy presented with unexplained splenomegaly, attention deficit hyperactivity disorder, mild learning difficulties, easy bruising, mild thrombocytopenia, and subtle dysmorphic features. Extensive haematological testing including a bone marrow biopsy showed mild megaloblastoid erythropoiesis and borderline fibrosis. There were no haematological cytogenetic anomalies or other haematological pathology to explain the splenomegaly. Metabolic testing and chromosomal microarray were unremarkable. Trio whole-exome sequencing (WES) identified a pathogenic de novo heterozygous germline CBL variant (c.1111T > C, p.Y371H), previously reported to cause CBL syndrome and implicated in development of juvenile myelomonocytic leukemia (JMML).

DISCUSSION

CBL syndrome (more formally known as "Noonan-syndrome-like disorder with or without juvenile myelomonocytic leukemia") has overlapping features to Noonan syndrome with significant variability. CBL syndrome and other RASopathy disorders-including Noonan syndrome, neurofibromatosis 1, and Costello syndrome-are important to recognize as these are associated with a cancer-predisposition. CBL syndrome carries a very high risk for JMML, thus accurate diagnosis is of utmost importance. The diagnosis of CBL syndrome in this patient would not have been possible based on clinical features alone. Through WES, a specific genetic diagnosis was made, allowing for an optimized management and surveillance plan, illustrating the power of genomics in clinical practice.

The lymphatic phenotype in Noonan and Cardiofaciocutaneous syndrome

The RASopathies, which include Noonan syndrome (NS) and Cardiofaciocutaneous syndrome (CFC), are autosomal dominant disorders with genetic heterogeneity associated with germline mutations of genes in the Ras/mitogen-activated protein kinase (MAPK; RAS-MAP kinase) pathway. The conditions overlap and are characterised by facial dysmorphism, short stature and congenital heart disease. NS and CFC, in particular, are known to be associated with lymphatic problems, but this has not been well characterised to date. We describe 11 patients with Noonan or CFC syndrome with significant, persistent and progressive lymphatic dysplasia. The lymphatic disorders in Noonan and CFC syndrome are rare, but have a characteristic pattern with bilateral lower limb lymphoedema, genital swelling with chylous reflux and frequent systemic involvement, including intestinal lymphangiectasia and chylothoraces, which may be progressive. Lymphoscintigraphy demonstrates reflux and/or rerouting of lymphatic drainage associated with incompetent veins on the venous duplex scans.

Juvenile myelomonocytic leukemia due to a germline CBL Y371C mutation: 35-year follow-up of a large family

Juvenile myelomonocytic leukemia (JMML) is a pediatric myeloproliferative neoplasm that arises from malignant transformation of the stem cell compartment and results in increased production of myeloid cells. Somatic and germline variants in CBL (Casitas B-lineage lymphoma proto-oncogene) have been associated with JMML. We report an incompletely penetrant CBL Y371C mutation discovered by whole-exome sequencing in three individuals with JMML in a large pedigree with 35 years of follow-up. The Y371 residue is highly evolutionarily conserved among CBL orthologs and paralogs. In silico bioinformatics prediction programs suggested that the Y371C mutation is highly deleterious. Protein structural modeling revealed that the Y371C mutation abrogated the ability of the CBL protein to adopt a conformation that is required for ubiquitination. Clinically, the three mutation-positive JMML individuals exhibited variable clinical courses; in two out of three, primary hematologic abnormalities persisted into adulthood with minimal clinical symptoms. The penetrance of the CBL Y371C mutation was 30% for JMML and 40% for all leukemia. Of the 8 mutation carriers in the family with available photographs, only one had significant dysmorphic features; we found no evidence of a clinical phenotype consistent with a "CBL syndrome". Although CBL Y371C has been previously reported in familial JMML, we are the first group to follow a complete pedigree harboring this mutation for an extended period, revealing additional information about this variant's penetrance, function and natural history.

Molecular Diversity and Associated Phenotypic Spectrum of Germline CBL Mutations

Noonan syndrome (NS) is a relatively common developmental disorder with a pleomorphic phenotype. Mutations causing NS alter genes encoding proteins involved in the RAS-MAPK pathway. We and others identified Casitas B-lineage lymphoma proto-oncogene (CBL), which encodes an E3-ubiquitin ligase acting as a tumor suppressor in myeloid malignancies, as a disease gene underlying a condition clinically related to NS. Here, we further explored the spectrum of germline CBL mutations and their associated phenotype. CBL mutation scanning performed on 349 affected subjects with features overlapping NS and no mutation in NS genes allowed the identification of five different variants with pathological significance. Among them, two splice-site changes, one in-frame deletion, and one missense mutation affected the RING domain and/or the adjacent linker region, overlapping cancer-associated defects. A novel nonsense mutation generating a v-Cbl-like protein able to enhance signal flow through RAS was also identified. Genotype-phenotype correlation analysis performed on available records indicated that germline CBL mutations cause a variable phenotype characterized by a relatively high frequency of neurological features, predisposition to juvenile myelomonocytic leukemia, and low prevalence of cardiac defects, reduced growth, and cryptorchidism. Finally, we excluded a major contribution of two additional members of the CBL family, CBLB and CBLC, to NS and related disorders.

An infant with a diagnostically challenging hepatic teratoma, hypofibrinogenemia, and adrenal neuroblastoma: case report

Teratomas of the liver are exceedingly rare. Neuroblastoma is the most common, extracranial solid tumor of infancy. We describe the case of a 2-month-old, female infant who presented with an abdominal mass arising in the right lobe of the liver, and a severe coagulopathy, which necessitated cryoprecipitate infusion. Biopsy was interpreted as hepatoblastoma. Following resection, difficulty classifying the mass led to several consultations, and an eventual diagnosis of teratoma. During follow-up, the patient was diagnosed with right adrenal neuroblastoma, which, in retrospect, had been present before the hepatic resection. To our knowledge, these 2 tumors have never been reported together, or in combination with isolated hypofibrinogenemia.

Hydrops, fetal pleural effusions and chylothorax in three patients with CBL mutations

Fetal hydrops, fetal pleural effusions, hydrothorax, and chylothorax, may be associated with various genetic disorders, in particular with the Noonan, cardio-facio-cutaneous and Costello syndromes. These syndromes, collectively called RASopathies, are caused by mutations in the RAS/MAPK pathway, which is known to play a major role in lymphangiogenesis. Recently, germline mutations in the Casitas B-cell lymphoma (CBL) gene were reported in 25 patients and of these, 20 had juvenile myelomonocytic leukemia (JMML). The disorder was named "CBL syndrome" or "Noonan syndrome-like disorder with or without juvenile myelomonocytic leukemia" (NSLL). To date, prenatal abnormalities have not been reported and it is still debated whether the CBL syndrome falls into the category of a RASopathy, or represents a different entity. Here we report on three unrelated patients with CBL mutations manifesting with hydrops fetalis, fetal pleural effusions and/or congenital hydro-/chylothorax. Our findings further connect the CBL syndrome with the RASopathies.