Encephalocraniocutaneous lipomatosis accompanied by the formation of bone cysts: Harboring clues to pathogenesis?

Encephalocraniocutaneous Lipomatosis, a Radiological Challenge: Two Atypical Case Reports and Literature Review

Encephalocraniocutaneous lipomatosis (ECCL; Haberland syndrome, #613001) is an extremely rare congenital disorder that is manifested by the involvement of the skin, eyes and central nervous system (CNS). We report two cases of children with ECCL diagnosis. First was an 8-year-old girl who presented with symptomatic epilepsy, cerebral palsy and developmental delay. In 2020, she was admitted to the hospital due to the exacerbation of paresis and intensified prolonged epileptic seizures, provoked by infection of the middle ear. Diagnostic imaging revealed radiological changes suggestive of ECCL, providing a reason for the diagnosis, despite the lack of skin and eye anomalies. The second child, a 14-year-old girl, was consulted for subtle clinical signs and epilepsy suspicion. Diagnostic imaging findings were similar, though less pronounced. Based on neuroradiological abnormalities typical for Haberland syndrome, the authors discuss possible ECCL diagnosis.

Expending the Phenotypic Spectrum of Encephalocraniocutaneous Lipomatosis: About a Prenatal Case With Complete Autopsy

Encephalocraniocutaneous lipomatosis (ECCL) or Haberland syndrome (MIM #613001) is a rare congenital neurocutaneous disorder. It is characterized by unilateral ocular, cutaneous and central nervous system anomalies. Key clinical features include hairless fatty tissue nevus of the scalp, choristoma of the eye and intraspinal and intracerebral lipomas. We report one of the first cases diagnosed after termination of pregnancy at 35 WG, including antenatal and post-mortem imaging, complete autopsy and genetic analysis. Prenatal ultrasound and MRI of the third trimester showed multifocal spinal lesions and left lateral cerebral ventriculomegaly with cerebral atrophy. Diagnosis of ECCL was suggested at complete autopsy which revealed nevus psiloliparus of the scalp, facial hamartomas and intracranial and spinal lipomas. In addition, our case also exhibited a cardiac rhabdomyoma and a multicystic dysplastic kidney, both never reported to date in this syndrome. ECCL was confirmed by the identification of a postzygotic FGFR1 mutation. We reviewed the literature and discuss the pathogenesis of this syndrome.

Encephalocraniocutaneous lipomatosıs (Haberland syndrome) in a newborn baby: a case report with review of literature

Encephalocraniocutaneous lipomatosis (ECCL) is an extremely uncommon, neurocutaneous disease, with a classical triad of ocular, skin lesions and central nervous system anomalies. We here report a case of ECCL in a newborn baby, characterized with naevus psiloliparus, choristoma, lipodermoids, cervical subcutaneous soft tissue mass, lowset ear, porencephalic cyst, polymicrogyria, arachnoid cyst, leptomeningeal angiomatosis and spinal lipomas. We here stress on the importance of early diagnosis to prevent misdiagnosis and employ a multidisciplinary approach in the management of these patients.

Pathogenic postzygotic mosaicism in the tyrosine receptor kinase pathway: potential unidentified human disease hidden away in a few cells

Mutations occurring during embryonic development affect only a subset of cells resulting in two or more distinct cell populations that are present at different levels, also known as postzygotic mosaicism (PZM). Although PZM is a common biological phenomenon, it is often overlooked as a source of disease due to the challenges associated with its detection and characterization, especially for very low-frequency variants. Moreover, PZM can cause a different phenotype compared to constitutional mutations. Especially, lethal mutations in receptor tyrosine kinase (RTK) pathway genes, which exist only in a mosaic state, can have completely new clinical manifestations and can look very different from the associated monogenic disorder. However, some key questions are still not addressed, such as the level of mosaicism resulting in a pathogenic phenotype and how the clinical outcome changes with the development and age. Addressing these questions is not trivial as we require methods with the sensitivity to capture some of these variants hidden away in very few cells. Recent ultra-accurate deep-sequencing approaches can now identify these low-level mosaics and will be central to understand systemic and local effects of mosaicism in the RTK pathway. The main focus of this review is to highlight the importance of low-level mosaics and the need to include their detection in studies of genomic variation associated with disease.

Case Report: A Case of Glioblastoma in a Patient With Haberland Syndrome

Haberland syndrome or encephalocraniocutaneous lipomatosis is a rare ectomesodermal dysgenesis defined by the triad including ocular, skin, and central nervous system involvement, which is commonly unilateral. This disorder is attributed to a post-zygotic mutation responsible for a neural tube and neural crest dysgenesis. We report the case of a 15-year-old female with Haberland syndrome with pharmacoresistant epilepsy who developed a World Health Organization-grade IV glioblastoma. This is the first case of pediatric glioblastoma associated with Haberland syndrome. The previously reported pediatric cases included benign brain tumors. To our knowledge, this is the fifth case of brain tumor associated with encephalocraniocutaneous lipomatosis and the second case of glioblastoma associated with this syndrome. The hypothesis that Haberland syndrome is associated with an increased risk of tumor development is intriguing, although the rarity of the condition is nowadays preventing us from drawing definitive conclusions about this potential link between the two entities. Further studies are needed to establish the real relationship between encephalocraniocutaneous lipomatosis and the risk of brain tumors.

Expansion of the phenotypic spectrum and description of molecular findings in a cohort of patients with oculocutaneous mosaic RASopathies

BACKGROUND

Postzygotic KRAS, HRAS, NRAS, and FGFR1 mutations result in a group of mosaic RASopathies characterized by related developmental anomalies in eye, skin, heart, and brain. These oculocutaneous disorders include oculoectodermal syndrome (OES) encephalo-cranio-cutaneous lipomatosis (ECCL), and Schimmelpenning-Feuerstein-Mims syndrome (SFMS). Here, we report the results of the clinical and molecular characterization of a novel cohort of patients with oculocutaneous mosaic RASopathies.

METHODS

Two OES, two ECCL, and two SFMS patients were ascertained in the study. In addition, two subjects with unilateral isolated epibulbar dermoids were also enrolled. Molecular analysis included PCR amplification and Sanger sequencing of KRAS, HRAS, NRAS, and FGFR1 genes in DNA obtained from biopsies (skin/epibulbar dermoids), buccal mucosa, and blood leukocytes. Massive parallel sequencing was employed in two cases with low-level mosaicism.

RESULTS

In DNA from biopsies, mosaicism for pathogenic variants, including KRAS p.Ala146Thr in two OES subjects, FGFR1 p.Asn546Lys and KRAS p.Ala146Val in ECCL patients, and KRAS p.Gly12Asp in both SFMS patients, was demonstrated. No mutations were shown in DNA from conjunctival lesions in two subjects with isolated epibubar dermoids.

CONCLUSION

Our study allowed the expansion of the clinical spectrum of mosaic RASopathies and supports that mosaicism for recurrent mutations in KRAS and FGFR1 is a commonly involved mechanism in these rare oculocutaneous anomalies.

A unique case of multiple non-ossifying fibromas with polyostotic monomelic distribution and aggressive clinical course

Multiple non-ossifying fibromas (MNOFs) occur either isolated or in association with other anomalies, are usually localized in the long bones of the lower limbs, may be radiographically confused with other skeletal lesions, and tend to heal spontaneously with the completion of the skeletal growth. Segmental distribution, either monomelic or polymelic and ipsilateral, is rare and commonly observed in the context of developmental diseases known as "RASopathies", which are caused by mutations in genes that encode components or regulators within the Ras/mitogen-activated protein kinase signaling pathway. We describe here the radiographic and pathologic features of an 18-year-old Caucasian boy, whose clinical history started at the age of 3 when the diagnosis of aneurysmal bone cyst was made on a lytic lesion of his left clavicle. Over the following 2 years, the patient developed polyostotic and monomelic lesions within the left humerus, radius, and ulna. No other skeletal and extra-skeletal anomalies were clinically detected. The lesions were interpreted as consistent with polyostotic fibrous dysplasia and MNOFs and showed an unusually aggressive clinical course with progressive increase in size and coalescence. The definitive diagnosis of MNOFs was made after the exclusion of fibrous dysplasia by molecular analysis. The polyostotic and monomelic distribution of the lesions and the unusually aggressive clinical course contribute to make this case of MNOFs unique.

Neuroimaging Findings in Pediatric Genetic Skeletal Disorders: A Review

Genetic skeletal disorders (GSDs) are a heterogeneous group characterized by an intrinsic abnormality in growth and (re-)modeling of cartilage and bone. A large subgroup of GSDs has additional involvement of other structures/organs beside the skeleton, such as the central nervous system (CNS). CNS abnormalities have an important role in long-term prognosis of children with GSDs and should consequently not be missed. Sensitive and specific identification of CNS lesions while evaluating a child with a GSD requires a detailed knowledge of the possible associated CNS abnormalities. Here, we provide a pattern-recognition approach for neuroimaging findings in GSDs guided by the obvious skeletal manifestations of GSD. In particular, we summarize which CNS findings should be ruled out with each GSD. The diseases (n = 180) are classified based on the skeletal involvement (1. abnormal metaphysis or epiphysis, 2. abnormal size/number of bones, 3. abnormal shape of bones and joints, and 4. abnormal dynamic or structural changes). For each disease, skeletal involvement was defined in accordance with Online Mendelian Inheritance in Man. Morphological CNS involvement has been described based on extensive literature search. Selected examples will be shown based on prevalence of the diseases and significance of the CNS involvement. CNS involvement is common in GSDs. A wide spectrum of morphological abnormalities is associated with GSDs. Early diagnosis of CNS involvement is important in the management of children with GSDs. This pattern-recognition approach aims to assist and guide physicians in the diagnostic work-up of CNS involvement in children with GSDs and their management.

Encephalocraniocutaneous Lipomatosis Without Ocular Malformations

BACKGROUND

Encephalocraniocutaneous lipomatosis is a rare congenital neurocutaneous syndrome resulting from ectomesodermal dysgenesis and characterized by unique hairless scalp lesions in the form of nevus psiloliparus, ipsilateral ocular malformations, and central nervous system anomalies. According to the 2009 diagnostic criteria proposed by Moog et al., ocular abnormalities are supposed to be the most consistent feature of encephalocraniocutaneous lipomatosis.

PATIENT DESCRIPTION

We describe an 18-year-old girl with most of the central nervous system manifestations of encephalocraniocutaneous lipomatosis, major skin alterations including nevus psiloliparus, but no ocular involvement.

CONCLUSION

Our patient suggests more variability in clinical features and a more complex genetic/embryonic etiology of encephalocraniocutaneous lipomatosis.

Mosaic Activating Mutations in FGFR1 Cause Encephalocraniocutaneous Lipomatosis

Encephalocraniocutaneous lipomatosis (ECCL) is a sporadic condition characterized by ocular, cutaneous, and central nervous system anomalies. Key clinical features include a well-demarcated hairless fatty nevus on the scalp, benign ocular tumors, and central nervous system lipomas. Seizures, spasticity, and intellectual disability can be present, although affected individuals without seizures and with normal intellect have also been reported. Given the patchy and asymmetric nature of the malformations, ECCL has been hypothesized to be due to a post-zygotic, mosaic mutation. Despite phenotypic overlap with several other disorders associated with mutations in the RAS-MAPK and PI3K-AKT pathways, the molecular etiology of ECCL remains unknown. Using exome sequencing of DNA from multiple affected tissues from five unrelated individuals with ECCL, we identified two mosaic mutations, c.1638C>A (p.Asn546Lys) and c.1966A>G (p.Lys656Glu) within the tyrosine kinase domain of FGFR1, in two affected individuals each. These two residues are the most commonly mutated residues in FGFR1 in human cancers and are associated primarily with CNS tumors. Targeted resequencing of FGFR1 in multiple tissues from an independent cohort of individuals with ECCL identified one additional individual with a c.1638C>A (p.Asn546Lys) mutation in FGFR1. Functional studies of ECCL fibroblast cell lines show increased levels of phosphorylated FGFRs and phosphorylated FRS2, a direct substrate of FGFR1, as well as constitutive activation of RAS-MAPK signaling. In addition to identifying the molecular etiology of ECCL, our results support the emerging overlap between mosaic developmental disorders and tumorigenesis.

Encephalocraniocutaneous lipomatosis, a rare neurocutaneous disorder: report of additional three cases

PURPOSE

Encephalocraniocutaneous lipomatosis (ECCL) is a rare congenital neurocutaneous disorder. It was described by Haberland in 1970 and is also called Haberland syndrome. It is characterized by unilateral skin lesions such as lipomas, connective tissue nevi, and alopecia with ipsilateral ophthalmological and cerebral malformations with or without psychomotor and mental retardation and early-onset seizure.

METHODS

We present three pediatric cases (two boys, one girl) with ECCL. All the patients' sociodemographic, clinical, and neuroradiological data was collected.

RESULTS

We describe two male (5 and 1.3 years old) and one female (15 years old) cases. All patients have unilateral left-sided alopecia with ipsilateral ocular lesion and the cerebral lesion. All patients were born at term; their past history and family histories were unremarkable. Their electroencephalograms showed hemispheric asymmetry. All of the cases had right-sided mild to moderate hemiparesis. In addition, our second case is having optic glioma and this case is the fifth case with glioma associated with ECCL.

CONCLUSIONS

We describe three additional cases with ECCL which is an extremely rare neurocutaneous syndrome. Also, case 2 has optic glioma and according to the literature this is the fifth case of low-grade gliomas with ECCL. We suggest that patients who have ocular lesion and ipsilateral skin lesion must be examined for ECCL, and the patients must be followed up with cerebral MRI once a year for low-grade gliomas.

Encephalocraniocutaneous Lipomatosis: A Rare Association With Tethered Spinal Cord Syndrome With Review of Literature

Encephalocraniocutaneous lipomatosis or Haberland syndrome is a rare, congenital neurocutaneous syndrome. It is characterized by unilateral lipomatous hamartomata of the scalp, eyelid, and outer globe of the eye and ipsilateral neurologic malformations. We describe the first case from Lebanon, an infant with classical encephalocraniocutaneous lipomatosis characterized by nevus psiloliparus, unilateral right facial and frontal–temporal subcutaneous lipomas, alopecia, ocular coloboma, aniridia and eyelid nodular tags, ventriculomegaly with intracranial and intraspinal lipomas, and tethered spinal cord. We report this case of rare association between encephalocraniocutaneous lipomatosis and tethered spinal cord syndrome and stress on the importance of spinal cord evaluation in encephalocraniocutaneous lipomatosis.

Are patients with encephalocraniocutaneous lipomatosis at increased risk of developing low-grade gliomas?

INTRODUCTION

Cancer-prone genetic disorders are responsible for brain tumors in a considerable proportion of children. Additionally, rare genetic syndromes associated to cancer development may potentially disclose genetic mechanisms related to oncogenesis.

METHOD

We describe two pediatric patients with encephalocraniocutaneous lipomatosis (ECCL), a very rare genetic syndrome with around 60 reported cases, which developed low-grade astrocytoma at 3 and 12 years of age.

RESULTS

Patients with ECCL seem to be at risk of benign forms of osseous tumors such as ossifying fibromas, odontomas, and osteomas.

CONCLUSION

The association between brain tumor and ECCL was previously reported only once, in a pediatric case of a mixed neuronal-glial histology. Whether ECCL may be a genetic condition of predisposing brain tumor in children strongly needs to be addressed.

Encephalocraniocutaneous lipomatosis: a review of its clinical pathology and neurosurgical indications

Encephalocraniocutaneous lipomatosis (ECCL) is a rare neurocutaneous syndrome whose hallmark lesions are benign lipomas of the brain and spinal cord. The authors present a case of a male infant with ECCL who had extensive brainstem and spinal cord lipomas. The management of this patient's hydrocephalus, cervicomedullary compression, tethered cord, and scoliosis over the course of his first 2 years of life is described. This case report and review of the literature is presented to provide a synopsis of the problems likely to be encountered by neurosurgeons who treat patients with this syndrome.

Papillary glioneuronal tumor present in a patient with encephalocraniocutaneous lipomatosis: case report

BACKGROUND AND IMPORTANCE

Encephalocraniocutaneous lipomatosis (ECCL) is a rare neurocutaneous syndrome presumably derived from a mesenchymal defect. No cases of ECCL associated with a neuroepithelial brain tumor have been described. Papillary glioneuronal tumor (PGNT) is also a rare brain tumor of mixed neuronal and glial cells. We believe this is the first case of ECCL combined with a PGNT to be described. The presence of the PGNT may reflect the maldevelopment of neuroepithelium in this ECCL patient and suggests a novel explanation of the pathogenesis of ECCL.

CLINICAL PRESENTATION

A 7-year-old girl with congenital lesions in the brain, spinal cord, eye, and skin was diagnosed with ECCL. Brain magnetic resonance images taken at 6 months of age showed no brain tumor other than stigmata of ECCL. Brain magnetic resonance image at the time of presentation at 7 years revealed a mass in the third ventricle. The tumor was completely removed, and pathological examination confirmed the diagnosis of PGNT. The tumor showed a divergent differentiation pattern both in the tissue histology and in primary cultures.

CONCLUSION

The occurrence of PGNT, a tumor resulting from the maldevelopment of neuroepithelium, broadens the spectrum of ECCL to include some defects in the neuroepithelium.

Low-grade astrocytoma in a child with encephalocraniocutaneous lipomatosis

Encephalocutaneous lipomatosis (ECCL), or Haberland syndrome, is an uncommon congenital disorder with unique cutaneous, ocular and neurological features. In the present article, we describe a 3-year-old boy with ECCL who developed an extensive and recurring intraventricular low-grade glioma with atypical pathological features and elevated mitotic index. Cytogenetic analysis from tumor sample was also performed. This is the first report of a low-grade astrocytoma occurring in a child with ECCL. Whether or not the origin of the tumor is associated to the pathogenesis of the underlying syndrome is a matter for further investigation.