The linear naevus sebaceus syndrome

Adnexal neoplasms of the eye

Adnexal neoplasms of the eyelid encompass a wide variety of benign and malignant tumors of sebaceous, follicular, and sweat gland origin. Due to the specialized structures of the eyelid, these neoplasms present differently when compared with those of other locations. Although most dermatologists and ophthalmologists are familiar with the commonly reported adnexal tumors of the eyelid, such as hidrocystoma, pilomatrixoma, and sebaceous carcinoma, many other adnexal neoplasms have been reported at this unique anatomic site. Accurate and timely identification of these neoplasms is essential, as alterations of eyelid anatomy and function can have a negative impact on eye health, vision, and quality of life. We review the clinical and histopathologic features of common and rare eyelid adnexal neoplasms and discuss proposed treatment options.

Searching beyond nevi - A rare case of neurocutaneous ocular syndrome

Epidermal nevus syndrome is a rare congenital disorder affecting only a few hundred people in the world. It has ophthalmic, dermatological, and neurological manifestations, with varied presentation. Here, we report a case of two-year-old child who presented with epibulbar mass in left eye, pigmented nevi over left side of the body and alopecia over left side of parieto-temporal scalp. Imaging confirmed epibulbar mass and presence of calcification of choroid on ipsilateral side with presence of arachnoid cyst of brain with underlying pachygyria. Neurological examination was normal and dermatologist confirmed presence of verrucous nevi over skin. Excisional biopsy of epibulbar mass revealed a complex choristoma with presence of lacrimal gland tissue. Underlying ocular findings were near normal with normal posterior segment. It is a rare form of epidermal nevus syndrome with near normal ocular findings in the presence of anterior and posterior choristoma, which has not been reported.

Renal Involvement in Linear Nevus Sebaceous Syndrome-An Underrecognized Feature

Linear nevus sebaceous syndrome (LNSS) is a rare neurocutaneous disorder. It is characterized by the presence of nevus sebaceous, ocular anomalies, neurological deficits, and convulsion. Renal involvement was not commonly reported. We report a 10-year-old girl with LNSS who had concomitant cystic kidney disease and diffuse aortopathy with bilateral renal artery stenosis, leading to hypertension requiring oral anti-hypertensive medications. The girl presented with chorioretinal coloboma and multiple nevus sebaceous at birth. She had aortic coarctation and received surgical repair at one week of life. She had persistent hypertension during her follow-up. Further investigations were performed to look for causes of hypertension apart from possible re-coarctation. Her magnetic resonance angiogram revealed diffuse aortopathy, which extended from the aortic arch to the abdominal aorta. Branches of the aorta, including the celiac trunk, superior mesenteric arteries, and renal arteries, were also narrowed. Multiple renal cysts were also identified in her right kidney. Interventional angioplasty over the renal arteries was not feasible due to diffuse narrowing of the aorta, especially at the origins of renal arteries. The blood pressure was controlled with oral anti-hypertensive medications. Our case illustrated that pediatricians should be aware of the possible renal involvements in LNSS, which impose a significant impact on the management and long-term prognosis of these patients.

Ophthalmic Manifestation and Pathological Features in a Cohort of Patients With Linear Nevus Sebaceous Syndrome and Encephalocraniocutaneous Lipomatosis

Purpose: This study aimed to figure out the association between ophthalmic and pathological features in patients with Linear Nevus Sebaceous Syndrome (LNSS) and in patients with Oculoectodermal Syndrome-Encephalocraniocutaneous Lipomatosis (OES-ECCL). Methods: It is a retrospective, non-consecutive, observational case series. Twenty-seven patients (12 with LNSS and 15 with OES-ECCL, 41 eyes) referred to the Department of Ophthalmology of the Shanghai Ninth People's Hospital between 2000 and 2020 were included. The mean age of the study population for the first-time consult was 5.7 years, ranging from 3 months to 34 years. Clinical notes, pathological records, and imaging findings were reviewed in all the patients. Results: Fourteen (51.9%) cases showed bilateral ocular involvement. Epibulbar choristomas were seen in all the patients. All the lesions involved the conjunctiva and cornea simultaneously. Multiple lesions were observed in 12 eyes. Of the 14 excised lesions, 11 were found to be complex choristomas. Further, 24 (89%) patients had eyelid coloboma. Also, 13 patients (48%) were diagnosed with strabismus, and 12 patients (44%) had abnormal fundus imaging, including optic nerve hypoplasia. Conclusions: LNSS and OES-ECCL shared common ophthalmic features, including epibulbar choristomas with distinctive characteristics, eyelid coloboma, strabismus, and optic nerve hypoplasia. The complex choristoma was found to be associated with the diseases. These specific patterns can be diagnostic clues to distinguish them from other syndromes, such as craniofacial defects, and to remind ophthalmologists that such patients require additional dermatological and neurological examinations and referral. Moreover, a thorough evaluation of ocular conditions is imperative for early interventions.

Schimmelpenning Syndrome with Large Nevus Sebaceous and Multiple Epidermal Nevi

Epidermal nevus syndromes are a group of rare multiorgan disorders. Schimmelpenning syndrome is a clinical variant of epidermal nevus syndromes. This congenital syndrome is characterized by the existence of nevus sebaceous and usually accompanied by abnormalities of the eyes, skeletal, cardiovascular, and central nervous systems. A 2-year-old girl presented with large, hairless, yellowish-brown plaques on the scalp and face along with multiple brownish-black verrucose plaques and brownish-black macules on almost all parts of the body. The skin-colored verrucose tumors were also found on the lips and around the mouth. Histopathological examination of the lesion on the forehead revealed hyperkeratosis, acanthosis, and sebaceous gland hyperplasia supporting the diagnosis of nevus sebaceous, while histopathological examination of the lesions on the lips and abdomen demonstrated hyperkeratosis, acanthosis, and papillomatosis consistent with verrucous epidermal nevus. The pediatrician suspected that the patient had mental retardation; however, there were no neurological, cardiac, skeletal, nor ophthalmologic abnormalities. The lesions on the lips and around the mouth were excised, and it demonstrated a good result. To conclude, epidermal nevus syndrome (e.g., Schimmelpenning syndrome) should be considered in children born with nevus sebaceous.

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.

Is Schimmelpenning Syndrome Associated with Intracranial Tumors? A Case Report

Schimmelpenning syndrome is a rare, well-defined constellation of clinical phenotypes associated with the presence of nevus sebaceous and multisystem abnormalities most commonly manifested as cerebral, ocular, and skeletal defects [<xref ref-type="bibr" rid="ref1">1</xref>]. A single nucleotide mutation in the HRAS or KRAS genes resulting in genetic mosaicism is responsible for the clinical manifestations of this syndrome in the majority of cases. We report a case of an adolescent boy with Schimmelpenning syndrome with a multifocal pilocytic astrocytoma. No HRAS or KRAS gene mutations were noted in the tumor on genetic sequencing. However, glial tumors have been associated with genetic mutations of RAS upregulation, which may imply a common pathway.

Syndromic sebaceous nevus: current findings

BACKGROUND

Sebaceous nevus is a congenital malformation of the skin that usually occurs on the scalp or face. Syndromic forms do rarely exist with associated cerebral and ocular malformations. The skin lesions are pale at birth and become irregular by puberty. In the adult patient, tumors (usually benign) develop from sebaceous nevus. Their surgical excision during childhood can give a better result in terms of the definitive scar.

OBJECTIVES

The aim of this study is to analyze our cases of syndromic sebaceous hamartoma, perform a review of the existing literature, and propose guidelines for the therapeutic plan.

METHODS

This is a retrospective study reviewing the cases of syndromic sebaceous nevus treated in the Department of Orthopedic Plastic Pediatric Surgery in Montpellier, France, and the Department of Pediatric Surgery in Lausanne, Switzerland, between 1994 and 2016.

RESULTS

The files of six patients with syndromic sebaceous nevus were analyzed. The average age at the first consultation was 4 months. The location was craniofacial in all cases. Cerebral radiological imaging was performed on all patients; two showed abnormal findings. Four patients underwent ophthalmic examination, which all revealed abnormalities. Three patients had other associated malformations. Three patients presented with epilepsy or learning difficulties in the course of follow-up.

CONCLUSION

All patients presenting with extensive sebaceous nevus of the craniofacial region should benefit from cerebral imagery and ophthalmic examination since there is a very high probability of associated abnormalities. The developmental problems encountered could not be definitively associated with the skin malformations.

Unusual Cause of West Syndrome

Schimmelpenning-Feuerstein-Mims syndrome is a congenital neurocutaneous disorder, comprising of organoid epidermal nevus with a broad spectrum of multiorgan dysfunction (neurologic, skeletal, cardiovascular, ophthalmic, and urologic) secondary to postzygotic mutation in the early embryonic period. Predominant neurological manifestations include epilepsy, intellectual impairment, and focal deficits. Here, we report a 3-year-old girl who presented with epileptic spasms and had a characteristic linear sebaceous nevus. This report not only highlights the importance of early diagnosis of this condition but also emphasizes the need for multiorgan screening in children with seizures and nevi.

Somatic KRAS mutation in an infant with linear nevus sebaceous syndrome associated with lymphatic malformations: A case report and literature review

RATIONALE

Linear nevus sebaceous syndrome (LNSS) is a rare neurocutaneous syndrome, characterized by nevus sebaceous,central nervous system (CNS), ocular and skeletal abnormalities. The present study describes KRAS somatic mosaic mutation in a case of LNSS with lymphatic malformations (LMs).

PATIENT CONCERNS

A 4-month-old female with a clinical diagnosis of LNSS presented with infantile spasms, mental retardation, skull dysplasia, ocular abnormalities, congenital atrial septal defect, and LMs.

DIAGNOSIS

Cervical ultrasonography revealed a 4.6 × 4.6 × 2.2cm no echo packet with clear boundary in the subcutaneous tissues of the right neck. The neck MRI indicated a cyst in the subcutaneous tissues of the right neck. Whole-exome sequencing revealed a low-level heterozygous mutation of the KRAS gene (c.35C > T; p.G12D, 19%) in the skin lesion sample. This mutation was not present in the blood samples of the patient and her parents.

INTERVENTIONS

The patient received sclerotherapy with paicibanil (OK-432) injection for the cyst.

OUTCOMES

Following 1 year of treatment, the patient exhibited fewer seizures. The mental and motor development was significantly improved. The patient can currently walk with assistance and speak simple words.

LESSONS

LNSS is a rare, congenital neurocutaneous syndrome consisting of a spectrum of abnormalities involving the skin, central nervous system, eyes, LMs and other systems. LNSS can be caused by postzygotic somatic mutation in the RAS family of genes. Multidisciplinary evaluation and treatment is needed.

Schimmelpenning syndrome: a case report and literature review

We report a case of a male newborn with Schimmelpenning syndrome, which presented as diffuse sebaceous nevi covering the left side of the body, from the lower chin midface to the lower leg; cardiac-ocular comorbidities were also present. We present photographs of this patient's sebaceous nevi, which may assist physicians in the early diagnosis of this condition and prevent unnecessary examinations and inadequate therapies.

Systemic abnormalities in children with congenital optic disc excavations

PURPOSE

Together with optic disc hypoplasia, excavated optic disc anomalies represent the most frequent congenital abnormality involving the optic nerve head. The purpose of the present study was to retrospectively review the results of a screening for extraocular abnormalities in children presenting with congenital optic disc excavations.

MATERIALS AND METHODS

The medical records of 37 patients diagnosed with a unilateral or bilateral non glaucomatous optic disc excavation were retrospectively reviewed to analyze the result of the extra ocular evaluation and to report the associated ocular abnormalities.

RESULTS

An ocular abnormality was observed in conjunction with the excavated optic disc in 31% of the eyes. The systematic investigations revealed the presence of at least one extra-ocular disorder in 48% of the cases, and the optic disc excavation could be considered as syndromic in 30% of patients. The prevalence of extraocular malformations was significantly higher in infants presenting with associated ocular malformations or abnormal vision/development.

CONCLUSIONS

The present study suggests that a systematic approach to search for any associated systemic abnormalities could be envisioned in patients presenting with congenital excavated optic discs, and particularly those presenting with abnormal vision, associated ocular defects or abnormal development.

Therapeutic effects of CO2 laser therapy of linear nevus sebaceous in the course of the Schimmelpenning-Feuerstein-Mims syndrome

The Schimmelpenning-Feuerstein-Mims (SFM) syndrome is a rare phakomatosis which comprises a nevus sebaceous of Jadassohn, seizures and developmental delay associated with a wide spectrum of extracutaneous abnormalities including neurological, skeletal, ocular, cardiovascular and urogenital defects. We are presenting a case of an 18-year-old patient with systemic features of the SFM syndrome and an extensive linear nevus sebaceous partially removed with a carbon dioxide (CO2) laser. The treatment options of skin lesions in patients with SFM are discussed.

Epidermal nevus syndrome

Epidermal nevus syndrome (ENS) is an inclusive term for a heterogeneous group of congenital disorders characterized by the presence of epidermal nevi associated with systemic involvement. These disorders, as are all primary neurocutaneous syndromes, are neurocristopathies. The epidermal nevi that follow the lines of Blaschko and most systemic anomalies in skeletal, ocular, cardiovascular, endocrine, and orodental tissues, as well as lipomas, are due to defective neural crest. The most important and frequent anomaly in the brain in all forms of epidermal nevus syndromes (ENSs) is hemimegalencephaly (HME). This malformation often is not recognized, despite being the principal cause of neurological manifestations in ENSs. They consist mainly of epilepsy and developmental delay or intellectual disability. The onset of epilepsy in ENS usually is in early infancy, often as infantile spasms. Several syndromic forms have been delineated. I propose the term "Heide's syndrome" for those distinctive cases with the typical triad of hemifacial epidermal nevus, ipsilateral facial lipoma, and hemimegalencephaly. Most ENSs are sporadic. The mechanism is thought to be genetic mosaicism with a lethal autosomal dominant gene. Specific genetic mutations (PTEN, FGFR3, PIK3CA, and AKT1) have been documented in some patients. The large number of contributors for over more than a century and a half to the description of these disorders precludes the use of new author eponyms.

Epidermal nevi

Nevi or nests of cells may be made up of a variety of cell types. The cell types that live in the epidermis include epidermal cells or keratinocytes, sebaceous glands, hair follicles, apocrine and eccrine glands, and smooth muscle cells. This article discusses epidermal or keratinocyte nevi, nevus sebaceous, nevus comedonicus, smooth muscle hamartomas, and inflammatory linear verrucous epidermal nevi. Syndromes associated with epidermal nevi are also reviewed.

Sebaceous lesions and their associated syndromes: part II

Sebaceous lesions are associated with two syndromes with widespread multisystem disorders and tumors. Linear sebaceous nevus syndrome has been traditionally known as the triad of sebaceous nevus of Jadassohn, seizures, and mental retardation. This syndrome encompasses a much broader spectrum of multisystem disorders, which is explored below. Muir-Torre syndrome is described as the presence of sebaceous tumors or keratoacanthomas with an underlying visceral malignancy. It is caused by mutations in DNA mismatch repair genes. We discuss its relationship with Lynch syndrome and suggest a comprehensive algorithm on how to screen patients with sebaceous neoplasms for Muire-Torre syndrome. We also provide suggested intensive cancer screening guidelines based on recommendations for patients with Lynch syndrome that may also be of value for patients with Muir-Torre syndrome.

Linear nevus sebaceous syndrome: case reports and review of the literature

Linear nevus sebaceous syndrome is reported to occur in as many as 1 in 1000 live births, and is hypothesized to result from genetic mosaicism involving a lethal autosomal-dominant gene. The terms "epidermal nevus syndrome" and "linear nevus sebaceous syndrome" are often used interchangeably, although linear nevus sebaceous syndrome more strictly applies to patients with a typical midline nevus, and epidermal nevus syndrome is a more inclusive term that includes all varieties of epidermal nevi. Linear nevus sebaceous syndrome encompasses a broad spectrum of abnormalities that may affect every organ system, including the central nervous system. In these cases, seizures and mental retardation are the main manifestations. Many other organ systems were also reported to be involved in this syndrome, including the cardiovascular, skeletal, ophthalmologic, and urogenital systems, among others. Although linear nevus sebaceous syndrome occurs at a relatively high frequency and may affect different organ systems, many physicians are unaware of the syndrome, which may delay diagnosis and treatment. We present two cases of linear nevus sebaceous syndrome, and we describe their initial presentation and subsequent evolution, incorporating a review of the current literature in this field.

Hemispherectomy in a premature neonate with linear sebaceous nevus syndrome

A male neonate with seizures, linear sebaceous nevus syndrome and hemimegalencephaly underwent hemispherectomy at 36 weeks' gestational age. He has had no clinical seizures in the 13 months since surgery but continues to have sharp wave activity over some parts of the intact hemisphere. He has moderate developmental delay and a mild hemiparesis but is making developmental progress.

A neuropathological study of two autopsy cases of syndromic hemimegalencephaly

Hemimegalencephaly (HMEG) is a malformation of cortical development characterized by unilateral enlargement of the cerebral hemisphere, severe architectural and cellular abnormalities and association with intractable epilepsy. HMEG may represent an isolated lesion of the central nervous system, but may also be associated with several neurocutaneous syndromes. In the present study we discuss the neuropathological findings of two autopsy cases of HMEG associated with linear naevus sebaceous syndrome. Both cases showed the presence of linear naevus sebaceous on extensive areas of the face. The neurochemical profile of the glial and neuronal components in the affected hemisphere was determined using immunocytochemical markers and was compared with the unaffected contralateral hemisphere and normal control tissue. The observed cytomegalic neurones expressed receptors for distinct neurotransmitters, neuropeptides and growth factors. Analysis of components of the phosphoinositide 3-kinase pathway revealed expression of phospho-S6 ribosomal protein in cytomegalic neurones. Autopsy findings confirm the complexity of the histologic phenotypic manifestations in HMEG and proved useful in determining the spectrum of cytoarchitectural and neurochemical abnormalities, underlying the molecular pathogenesis and epileptogenesis of this brain malformation.

Diagnosis and management of benign lumps and bumps in childhood

PURPOSE OF REVIEW

In every pediatric practice, skin disorders make up a large percentage of outpatient visits. In this article, we highlight three of the most common 'lumps and bumps' seen in childhood: nevus sebaceus, pilomatricoma and juvenile xanthogranuloma.

RECENT FINDINGS

Historically, many authors have advocated the prompt removal of nevus sebaceus at a young age due to the risk of malignant growths arising in these lesions during childhood. Recent articles have revisited this issue, concluding that the actual incidence of malignant growths in nevus sebaceus is quite rare in young patients. Regarding pilomatricomas, new findings show that the clinical accuracy of primary care physicians in diagnosing a pilomatricoma is low. With the identification of several key features, these lesions can be more easily diagnosed. Finally, the association of juvenile xanthogranuloma with neurofibromatosis and chronic juvenile myeloid leukemia has been described more formally in the recent literature, but the incidence and true association of this triad remain debatable.

SUMMARY

Several updates in the recent literature now afford greater understanding of these three benign pediatric tumors. With greater familiarity, an accurate diagnosis can often be made in the office and informed counseling regarding the risks or associations of these specific skin lesions can be performed.

Hemimegalencephaly: clinical implications and surgical treatment

INTRODUCTION

Hemimegalencephaly (HME) is a quite rare malformation of the cortical development arising from an abnormal proliferation of anomalous neuronal and glial cells that generally leads to the hypertrophy of the whole affected cerebral hemisphere. The pathogenesis of such a complex malformation is still unknown even though several hypotheses are reported in literature.

BACKGROUND

HME can occur alone or associated with neurocutaneous disorders, such as neurofibromatosis, epidermal nevus syndrome, Ito's hypomelanosis, and Klippel-Trenonay-Weber syndrome. The clinical picture is usually dominated by a severe and drug-resistant epilepsy. Other common findings are represented by macrocrania, mean/severe mental retardation, unilateral motor deficit, and hemianopia. The EEG shows different abnormal patterns, mainly characterized by suppression burst and/or hemihypsarrhythmia. Although neuroimaging and histologic investigations often show typical findings (enlarged hemisphere, malformed ventricular system, alteration of the normal gyration), the differential diagnosis with other disorders of the neuronal and glial proliferation may be difficult to obtain. Hemispherectomy/hemispherotomy is the most effective treatment to control seizure, and it also seems to provide good results on the psychomotor development when performed early, as demonstrated by the literature review and by the reported personal series reported here (20 children). The surgical therapy of HME, however, is still burdened by a quite high complication rate and mortality risk.

Sonographic characteristics of linear nevus sebaceous sequence

Linear nevus sebaceous is a hamartomatous lesion most commonly seen on the face and head of infants and diagnosed after birth. We describe a patient with sonographic findings of linear nevus sebaceous seen initially at 30 weeks' gestation. Other associated sonographic findings include macrocephaly and polyhydramnios. When associated with a midline soft tissue mass, these findings are highly suggestive of the presence of congenital linear nevus sebaceous sequence.

[The skin as an expression of neurological alterations in the neonate]

The skin is involved in many different genetic syndromes and diseases with multiple organ involvement. Neurodevelopmental disorders appear in many of these entities and knowledge of these cutaneous alterations may provide clues to their diagnosis. Recognizing these skin disorders in the newborn allows early identification of neonates with a biological risk of epilepsy and motor and/or cognitive disorders and enables them to be followed up. This helps to plan the management of these patients and, in many entities, to predict their natural history and provide genetic counseling to the family. This review examines the cutaneous signs that may provide important clues in the neonate that help to identify entities that carry a risk of neurodevelopmental disorders in the neonate.

The rare phakomatoses

This article outlines the clinical, central nervous system, and neuropathologic features,pathogenesis, genetics, molecular biology, and neuroimaging characteristics of the rare vascular phakomatoses, melanophakomatoses, and organoid phakomatoses.

Tc-99m HMPAO brain SPECT in linear nevus sebaceous syndrome

The authors present a case of linear nevus sebaceous syndrome (LNSS) with atrophy of bilateral frontotemporal areas of the brain, left cerebellum and hippocampus, and bilateral uncal dysplasia demonstrated by magnetic resonance imaging (MRI). Magnetic resonance angiography revealed bilateral internal carotid artery hypoplasia with absence of flow in the anterior and middle cerebral arteries. Tc-99m HMPAO brain SPECT demonstrated more areas of perfusion defects while MRI detected volume loss and gliosis in affected areas. Tc-99m HMPAO brain SPECT may be more useful for revealing absent or decreased perfusion areas of brain lesions than MRI in LNSS.

Surgical management of the cutaneous manifestations of linear nevus sebaceus syndrome

Linear nevus sebaceus syndrome is characterized by the association of nevus sebaceus covering extensive areas on the head and scalp with abnormalities of the central nervous system, ophthalmologic and skeletal changes, and malignancies. The incidence is approximately one per 10,000 live births, and there is no sexual predilection reported. The original description of this syndrome was followed by extensive literature describing the dermatologic, neurologic, and ophthalmologic manifestations of this disease. The objective of this report is to describe the surgical approach for the excision and reconstruction of giant sebaceous nevi of the face and scalp in children with linear nevus sebaceus syndrome on the basis of a consecutive series of five patients treated over 10 years in the same institution. To the authors' knowledge, this report represents the largest surgical series and suggests a reliable approach to the treatment of the cutaneous manifestations of this syndrome.

Desmoplastic Neuroepithelial Tumor of Infancy in the Nevus Sebaceus Syndrome

The nevus sebaceus syndrome (NSS) is a neurocutaneous disorder characterized by unilateral hyperplasia of skin appendages and skeletal hemihypertrophy, hemimegalencephaly, or hemiatrophy along with disabling seizures. Despite the proneness of the dermal stigmata to eventually undergo neoplastic transformation, the malformative lesions of the central nervous system rarely evolve into frank tumors. We present the case of a 10-year-old girl with left-sided sebaceus nevi, ipsilateral enlargement of the skull, and a desmoplastic neuroepithelial tumor (DNET) in the right fronto-parietal area of the brain. The tumor was removed by surgery. Histologically, it corresponded to a mitotically active small-cell anaplastic astrocytoma with genuine desmoplasia. Investigative methods included immunohistochemical positivity for glial fibrillary acidic protein, lack of expression of neuronal markers, and ultrastructural documentation of sheaths of basal lamina and collagen around tumor cells. A survey of the literature of brain tumors associated with NSS revealed two cases of histologically verified pilocytic astrocytomas, and one each of a choroid plexus papilloma, a mixed glioma, and a meningioma, as well as a subependymal giant cell astrocytoma--the latter possibly in an overlap syndrome of NSS and tuberous sclerosis. We hypothesize that the tumor described herein, one involving both atypical differentiation and enhanced growth potential, is paradigmatic of neuropathological events to be expected in the NSS.