The epidermal nevus syndrome

Phacomatosis spilosebacea: A new name for a distinctive binary genodermatosis

Phacomatosis pigmentokeratotica (PPK) is defined by the association of papular nevus spilus arranged in a flag-like pattern and sebaceous nevus following Blaschko's lines. A systematic search of the worldwide literature retrieved 95 well-established PPK cases. An additional 30 cases were excluded for a number of reasons. Based on this study, we propose to rename PPK phacomatosis spilosebacea (PSS). Mosaic mutations of the HRAS gene are the only proven cause of PSS. The extracutaneous abnormalities of PSS result from various degrees of intermingling of Schimmelpenning syndrome and papular nevus spilus syndrome. PSS seems to be a condition at particularly high risk of developing basal cell carcinoma, urogenital malignancies, and vitamin D-resistant hypophosphatemic rickets. Extracutaneous abnormalities were detected in approximately 75% of PSS cases.

Linear Epidermal Nevus: A Case Report With Oral and Facial Manifestations

A 20-year-old man presented to the oral and maxillofacial surgery department for evaluation and treatment of a dentofacial deformity. On examination, it was noted that he had marked hemifacial hyperpigmented papillomatous lesions covering the upper and middle thirds of the right side of his face extending to the right upper lid. Of note, he also had extensive intraoral involvement. These features were highly suggestive of linear epidermal nevus, a congenital hamartomatous lesion of the ectoderm. Linear epidermal nevus with oral manifestations is extremely rare with very few cases reported in the medical literature.

Epidermal nevus syndromes

The term epidermal nevus syndrome (ENS) has been used to describe the association of epidermal hamartomas and extracutaneous abnormalities. Although many continue to use the term "ENS," it is now understood that this is not one disease, but rather a heterogeneous group with distinct genetic profiles defined by a common cutaneous phenotype: the presence of epidermal and adnexal hamartomas that are associated with other organ system involvement. One commonality is that epidermal nevi often follow the lines of Blaschko and it appears the more widespread the cutaneous manifestations, the greater the risk for extracutaneous manifestations. The majority of the extracutaneous manifestations involve the brain, eye, and skeletal systems. The CNS involvement is wide ranging and involves both clinical manifestations such as intellectual disability and seizures, as well as structural anomalies. Several subsets of ENS with characteristic features have been delineated including the nevus sebaceus syndrome, Proteus syndrome, CHILD syndrome, Becker's nevus syndrome, nevus comedonicus syndrome, and phakomatosis pigmentokeratotica. Advances in molecular biology have revealed that the manifestations of ENS are due to genomic mosaicism. It is likely that the varied clinical manifestations of ENS are due in great part to the functional effects of specific genetic defects. Optimal management of the patient with ENS involves an interdisciplinary approach given the potential for multisystem involvement. Of note, epidermal nevi have been associated with both benign and malignant neoplasms, and thus ongoing clinical follow-up is required.

Two Concurrent Facial Epidermal Nevi without Systemic Abnormalities: Nevus Sebaceus and Nevus Comedonicus

Epidermal nevi (EN) are hamartomatous lesions derived from epidermal components originating from pluripotent cell mutations. They have been categorized according to their predominant component. The existence of >2 types of EN concurrently within a single area or within contiguous areas has been rarely reported. This report describes the case of simultaneous presence of a yellowish plaque on the left medial canthus and an aggregation of closed comedo-like papules on the right side of the cheek of a 15-year-old girl.

Epidermal nevus and ameloblastoma: a rare association

Epidermal nevi are clinical manifestations of a malformation affecting the embryonic ectoderm. They appear as linear verrucous lesions and are more often located in the skin of the trunk or the extremities. Rarely, verrucous lesions affect the oral mucosa. Epidermal nevi can be a component of epidermal nevus syndrome (ENS), which is characterized by malformations involving several organs, such as the central nervous system. ENS is rarely associated with other solid tumors. We present the case of a patient affected by ENS who developed maxillary and mandibular ameloblastomas. Epidermal nevi were located in the left middle and lower third of the face and in the left cervical region, whereas the ameloblastomas arose within the left maxillary mucosa and within the left mandibular ramus. Features of the syndrome are described and the relevant literature is reviewed.

The group of epidermal nevus syndromes Part I. Well defined phenotypes

The epidermal nevus syndromes represent a group of distinct disorders that can be distinguished by the type of associated epidermal nevus and by the criterion of presence or absence of heritability. Well defined syndromes characterized by organoid epidermal nevi include Schimmelpenning syndrome, phacomatosis pigmentokeratotica, nevus comedonicus syndrome, angora hair nevus syndrome, and Becker nevus syndrome. The molecular basis of these disorders has so far not been identified. By contrast, the group of syndromes characterized by keratinocytic nevi comprises three phenotypes with a known molecular etiology in the form of CHILD (congenital hemidysplasia with ichthyosiform nevus and limb defects) syndrome, type 2 segmental Cowden disease, and fibroblast growth factor receptor 3 epidermal nevus syndrome (García-Hafner-Happle syndrome), whereas Proteus syndrome is still of unknown origin. From this overview, it is clear that a specific type of these disorders cannot be classified by the name "epidermal nevus syndrome" nor by the terms "organoid nevus syndrome" or "keratinocytic nevus syndrome."

LEARNING OBJECTIVES

After completing this learning activity, participants should be able to distinguish nine different epidermal nevus syndromes by their characteristic features, understand the practical significance of avoiding terms like "epidermal nevus syndrome" or "keratinocytic nevus syndrome" to define any specific entity within this group of disorders, and differentiate between nonhereditary traits and those bearing a genetic risk because of either Mendelian or non-Mendelian inheritance.

Nevus marginatus: a distinct type of epidermal nevus or merely a variant of nevus sebaceus?

Epidermal nevi (EN) represent a heterogeneous group of mosaic skin lesions frequently following the lines of Blaschko. They are divided into organoid and nonorganoid types. Herein we report on a 35-year-old man with a rather unusual type of EN. A linear lesion involving the trunk and following Blaschko's lines was conspicuously bordered by dark brown papules. The flat reddish central area histopathologically showed sebaceous hyperplasia consistent with nevus sebaceus, an organoid EN type, whereas the elevated margin showed features of a common nonorganoid keratinocytic EN. For this peculiar disorder, we propose the term 'nevus marginatus'. So far it is not clear whether nevus marginatus represents a distinct entity or merely an unusual clinical variant of nevus sebaceus.

Epidermal nevus syndrome and didymosis aplasticosebacea

The epidermal nevus syndrome is a disease complex consisting of the association of an epidermal nevus with various developmental abnormalities of the skin, eyes, nervous, skeletal, cardiovascular, and urogenital systems. The epidermal nevi are classified according to their predominant component; nevus sebaceus (sebaceous glands), nevus comedonicus (hair follicles), and nevus verrucosus (keratinocytes). We report a neonate who presented with a nevus sebaceus on the scalp and face as well as a coloboma and dermoid on his left eye. Within the sebaceous nevus on the scalp, circumscribed lesions of aplasia cutis congenita were detected, which is consistent with the recently proposed term in the literature didymosis aplasticosebacea.

Epidermal nevus syndrome associated with adnexal tumors, spitz nevus, and hypophosphatemic vitamin D-resistant rickets

The epidermal nevus syndrome is the association of epidermal nevi with abnormalities in other organ systems, most commonly the central nervous system, the skeletal system, and the eyes. We present a patient with epidermal nevus syndrome associated with hypophosphatemic vitamin D-resistant rickets and multiple adnexal and spindle cell tumors.

Epidermal nevus syndromes

The term "epidermal nevus syndrome" (ENS) has been used to describe the association of epidermal hamartomas and extra-cutaneous abnormalities. Epidermal nevi follow the lines of Blaschko. The majority of the extra-cutaneous manifestations involve the brain, eye, and skeletal systems. Several subsets with characteristic features have been delineated including the nevus sebaceous syndrome, Proteus syndrome, CHILD syndrome, Becker nevus syndrome, nevus comedonicus syndrome, and phakomatosis pigmentokeratotica. Epidermal nevi have been associated with benign and malignant neoplasms. Advances in molecular biology have revealed that the manifestations of ENS are due to genomic mosaicism. It is likely that the varied clinical manifestations of ENS are due in great part to the functional effects of specific genetic defects. Optimal management of the patient with ENS involves an interdisciplinary approach. Amelioration of the cutaneous features of ENS has been difficult but there have been advances, especially in the use of lasers.

The epidermal nevus syndromes: multisystem disorders

The epidermal nevus syndromes are a group of congenital syndromes comprising epidermal nevi in conjunction with central nervous system (CNS), ocular, musculoskeletal, and other organ anomalies. We describe a patient with epidermal nevi and multiple organ abnormalities, highlighting the wide spectrum of involvement in epidermal nevus syndromes, and briefly summarize the literature on these rare syndromes.

A novel epidermal nevus syndrome with congenital cylindromatous turban tumor

BACKGROUND

Epidermal nevi (in the broad sense of epithelial nevi) may give rise to benign or malignant skin tumors. They may also be associated with anomalies of other organ systems in an epidermal nevus syndrome.

RESULTS

This article describes a preterm infant with nevus sebaceus of the scalp and face, a large turban tumor with features of malignant cylindroma and multiple non-cutaneous defects. These included skeletal, hematopoietic, hepatobiliary, and urinary anomalies. Severe secondary lesions were present (pulmonary hypoplasia due to oligohydramnios; cerebral infarcts probably related to the turban tumor). Karyotype was normal, and family history was negative.

CONCLUSIONS

This unique case is unlike any reported epidermal nevus syndrome. Similarly, there is no prior report of a congenital cylindroma, certainly not as a turban tumor, which implies very rapid growth. The presence of both overgrowth and undergrowth phenomena (e.g. hypoplastic urinary tract and biliary atresia) may reflect dysregulation of paracrine growth factors, presumably due to genetic mutation.

Epidermal nevus syndrome with development of a mandibular ameloblastoma

Epidermal nevus syndrome (ENS) is a hamartoneoplastic syndrome characterized by the association of epidermal nevi with abnormalities in other organ systems. We report a 32-year-old woman with ENS that, in addition to cutaneous manifestations, showed red plaques on the maxillary and mandibular labial alveolar mucosa and a papillomatous lesion of the midline posterior hard palate. Radiographic examination of the jaws was noncontributory. Approximately 5 years later, a follicular ameloblastoma developed in the mandible. The tumor showed duct-like cystic spaces, continuity with the overlying epithelium, and globular myxomatous areas in the connective tissue. The palatal lesion was diagnosed as papilloma, whereas the maxillary plaques showed nonspecific mucositis. The association of ameloblastoma with ENS is discussed. This is the second case of ENS associated with ameloblastoma reported in the medical literature.

Epidermal nevus syndrome with hypermelanosis and chronic hyponatremia

Epidermal nevus syndrome is seldom encountered, and its association with hypermelanosis and the chronic syndrome of inappropriate antidiuretic hormone secretion (SIADH) has never been reported. A male neonate who developed intractable seizures and hyponatremia soon after birth is reported. He had alopecic patches on the scalp at birth. Large areas of skin hyperpigmentation, and epidermal nevi developed gradually. The clinical picture of hypotonic hyponatremia, high urine osmolality, elevated urine sodium, and euvolemia was compatible with SIADH. The seizures did not correlate with the hyponatremia, and no other cause for the seizures could be identified. The hyponatremia became chronic and was treated with a direct supply of sodium chloride. The development of the patient was markedly delayed at the last visit when he was 1 year of age. It is suggested that hypermelanosis and chronic SIADH may also be a variant presentation of epidermal nevus syndrome.

Adult onset verrucous epidermal nevus

Epidermal nevi are hamartomas of the skin and have multiple clinical variants, including a verrucous type. Usually verrucous epidermal nevi present at an early age, are found on the lower extremities, have a female predominance, and are refractory to treatment. Only very rarely do verrucous epidermal nevi have an adult onset. We describe a 60-year-old woman with a 5-year history of multiple verrucous plaques on her face, scalp, and neck. Histologic examination revealed the characteristic findings of verrucous epidermal nevus. This is the oldest patient reported with an adult onset verrucous epidermal nevus.

Linear sebaceous nevus syndrome: report of a patient with unusual associated abnormalities

A 9-year-old girl was diagnosed as having a linear sebaceous nevus syndrome (LSNS). The nevus sebaceus was located on the face, and the girl also had nevoid hypertrichosis on the neck, sensorineural deafness, partial anodontia, blocked tear ducts, labiopalatoschisis, and an area of micropolygyria in the left encephalic (cerebral) hemisphere. Electroencephalographic alterations were detected, but they were not accompanied by a history of seizures; furthermore, the child was not mentally retarded. This phenotypic pattern of LSNS is unusual for the rarity of associated abnormalities.

Epidermal nevus syndromes

A clinical entity called "the epidermal nevus syndrome" does not exist. Rather, there are various epidermal nevus syndromes that can be distinguished by clinical, histopathological, and genetic criteria. In this review, five distinct epidermal nevus syndromes, recognizable by different types of associated epithelial nevi, are described. The Schimmelpenning syndrome is characterized by a sebaceous nevus associated with cerebral anomalies, coloboma, and lipodermoid of the conjunctiva. By contrast, cataracts are a prominent feature of the nevus comedonicus syndrome. The pigmented hairy epidermal nevus syndrome includes Becker nevus, ipsilateral hypoplasia of the breast, and skeletal defects such as scoliosis. In the Proteus syndrome, the associated epidermal nevus is of a flat, velvety, nonorganoid type. The CHILD syndrome occurs almost exclusively in girls. The associated CHILD nevus shows unique features such as a diffuse form of lateralization, ptychotropism, and microscopic changes of verruciform xanthoma. The five epidermal nevus syndromes differ in their genetic basis. The Schimmelpenning and nevus comedonicus syndromes are most likely nonhereditary traits. By contrast, the pigmented hairy epidermal nevus syndrome and the Proteus syndrome may be explained by paradominant inheritance. The CHILD syndrome is caused by an X-linked dominant mutation exerting a lethal effect on male embryos. A correct diagnosis of these phenotypes is important for both recognition and treatment of associated anomalies as well as for genetic counseling.

Myelomeningocele, spinal arteriovenous malformations and epidermal nevi syndrome: a possible rare association?

A 20-year-old woman with myelomeningocele presented with acute right-ear pain and right hemiplegia which improved, but then progressively deteriorated. Surgery, after MRI, revealed a large arteriovenous malformation (AVM) involving the right side of the upper cervical cord and brainstem. The woman also had two epidermal nevi at the same site as the spinal cord AVMs. There has been no previous report of an association of myelomeningocele, spinal cord AVMs and epidermal nevi syndrome. The same location of the nevus and spinal cord AVMs, with a proposed common pathogenesis, raise the possibility that the association may be more than chance occurrence. Spinal cord AVMs should be considered in patients with myelomeningocele and similar clinical features.