The Experts below are selected from a list of 297 Experts worldwide ranked by ideXlab platform
Rudolf Happle - One of the best experts on this subject based on the ideXlab platform.
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Papular Nevus spilus syndrome: old and new aspects of a mosaic RASopathy
European Journal of Dermatology, 2019Co-Authors: Daniele Torchia, Rudolf HappleAbstract:The co-existence of papular Nevus spilus (PNS) and ipsilateral extracutaneous abnormalities involving peripheral nerves of the skin or muscles was originally described as “speckled lentiginous Nevus syndrome”. To avoid confusion with macular Nevus spilus, the condition was recently re-named “papular Nevus spilus syndrome”. In addition to 14 published cases, we identified six new cases via a search of the worldwide literature. New diagnostic criteria are suggested: (1) presence of a PNS; (2) presence of a neurological or skeletal abnormality which is usually ipsilateral to the Nevus; and (3) absence of a Nevus sebaceus. According to current knowledge, PNS syndrome is a rather rarely occurring, sporadic disorder that can be considered to be part of a spectrum of mosaic RASopathies, which includes isolated PNS, isolated Nevus sebaceus, PNS syndrome, Schimmelpenning syndrome, and phacomatosis pigmentokeratotica.
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the group of epidermal Nevus syndromes part i well defined phenotypes
Journal of The American Academy of Dermatology, 2010Co-Authors: Rudolf HappleAbstract: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 ( c ongenital h emidysplasia with i chthyosiform Nevus and l imb d efects) syndrome, type 2 segmental Cowden disease, and fibroblast growth factor receptor 3 epidermal Nevus syndrome (Garcia-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.
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the group of epidermal Nevus syndromes
Journal of The American Academy of Dermatology, 2010Co-Authors: Rudolf HappleAbstract: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 ( c ongenital h emidysplasia with i chthyosiform Nevus and l imb d efects) syndrome, type 2 segmental Cowden disease, and fibroblast growth factor receptor 3 epidermal Nevus syndrome (Garcia-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.
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Trichilemmal cyst Nevus: a new complex organoid epidermal Nevus.
Journal of The American Academy of Dermatology, 2007Co-Authors: Iliana Tantcheva-poor, Katja Reinhold, Thomas Krieg, Rudolf HappleAbstract:A 31-year-old woman had an organoid Nevus characterized by multiple trichilemmal cysts arranged in a bandlike pattern. The involved streaks followed Blaschko's lines and were covered, in addition, by multiple filiform hyperkeratoses and comedo-like plugs. Some histopathologic features of this complex Nevus were reminiscent of those of well-established organoid nevi such as Nevus comedonicus, porokeratotic eccrine Nevus, or hair follicle Nevus, but the presence of multiple large trichilemmal cysts was a conspicuously distinctive abnormality. Consequently, we propose for this new organoid Nevus the names " trichilemmal cyst Nevus" or "Nevus trichilemmocysticus."
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Becker Nevus Syndrome
Actas Dermo-Sifiliográficas, 2007Co-Authors: A. Alfaro, Antonio Torrelo, Á. Hernández, Antonio Zambrano, Rudolf HappleAbstract:Becker Nevus is a hyperpigmented hamartoma with an irregular outline and often hairy. It is normally found on the shoulders and chest, although it can appear in other areas. Becker Nevus is sometimes associated with other muscular, skeletal, or cutaneous abnormalities such as ipsilateral breast hypoplasia or scoliosis. This characteristic phenotype of Becker Nevus associated with unilateral breast hypoplasia or other abnormalities is referred to as Becker Nevus syndrome. Although the lesions usually become apparent during adolescence, they are present from birth and represent part of the spectrum of so-called epidermal Nevus syndromes. We present 4 cases of Becker Nevus syndrome in which Becker Nevus was associated with ipsilateral breast hypoplasia and, less consistently, other abnormalities.
Guido Massi - One of the best experts on this subject based on the ideXlab platform.
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Nevus Spilus (Speckled lentiginous Nevus)
Histological Diagnosis of Nevi and Melanoma, 2020Co-Authors: Guido Massi, Philip E LeboitAbstract:We define Nevus spilus as a medium-sized, or large, cafe au lait macule speckled with melanocytic nevi. The definition is incorrect and imprecise but it is very entrenched in the common dermatological jargon and it is less cumbersome than others which are nosologically more appropriate. The French literature refers to this entity as “Nevus en Nevus”.
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Dysplastic Nevus, Clark Nevus or Common Nevus?
Histological Diagnosis of Nevi and Melanoma, 2020Co-Authors: Guido Massi, Philip E LeboitAbstract:In 1978 Clark and his colleagues put forth a hypothesis that still provokes controversy — the idea that a set of findings in nevi of members of families with a tendency to develop melanoma was a clinicopathologic entity, representing an intermediate step between the “common Nevus” and melanoma. The dysplastic Nevus is still a controversial entity with some specific clinical and histological characteristics, but with “fuzzy” borders. The dividing line between a “common Nevus” at the lower end and melanoma in situ or superficially invasive melanoma at the upper end defies precise characterization, similar to that in other “intermediate” lesions in pathology.
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Clark Nevus and Dysplastic Nevus
Histological Diagnosis of Nevi and Melanoma, 2014Co-Authors: Guido Massi, Philip E LeboitAbstract:1978, Wallace Clark and his colleagues set forth a hypothesis that still has some controversial aspects – the idea that a set of fi ndings in nevi of members of families with a tendency to develop melanoma comprise a clinicopathological entity, representing an intermediate step between the “common Nevus” and melanoma. While few would dispute that the clinical phenotype of many large, atypical appearing nevi is a marker for an increased risk of melanoma and tends to be inherited, many of the melanomas in these patients arise de novo rather than in preexistent lesions. Just how distinctive these nevi are and whether they pose a risk for the development of melanoma within the lesions themselves that is different from that of other nevi are still debated. Clark and his colleagues coined the term dysplastic Nevus to highlight their belief that the lesions in question were partially transformed neoplasms, within the same realm of precancerous alterations found in other organs.
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Halo Nevus (Regressing Nevus)
Histological Diagnosis of Nevi and Melanoma, 2013Co-Authors: Guido Massi, Philip E LeboitAbstract:Histologically, the so-called halo Nevus is overwhelmed by an infl ammatory, mostly lymphocytic infi ltrate with extensive loss of melanocytes. The clinically evident white halo corresponds to the loss of melanin in the basal layer of the epidermis and to a reduction in the number of melanocytes.
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Melanocytic nevi simulant of melanoma with medicolegal relevance
Virchows Archiv, 2007Co-Authors: Guido MassiAbstract:A group of melanocytic benign nevi are prone to be misdiagnosed as nodular or superficial spreading melanoma. This review illustrates the most frequent forms of these nevi in direct comparison with their malignant morphologic counterparts. The nevi are: hyper-cellular form of common Nevus to be distinguished from nevoid melanoma, Spitz Nevus (vs spitzoid melanoma), Reed Nevus (vs melanoma with features of Reed Nevus), cellular atypical blue Nevus (vs melanoma on blue Nevus), acral Nevus (vs acral melanoma), Clark dysplastic Nevus (vs superficial spreading melanoma), desmoplastic nevi (vs desmoplastic melanoma), benign proliferative nodules in congenital nevi (vs melanoma on congenital nevi), epithelioid blue Nevus (vs animal type melanoma) and regressed Nevus (vs regressed melanoma). For each single ‘pair’ of morphological look-alikes, a specific set of morphological, immunohistochemical and genetic criteria is provided.
Philip E Leboit - One of the best experts on this subject based on the ideXlab platform.
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Dysplastic Nevus, Clark Nevus or Common Nevus?
Histological Diagnosis of Nevi and Melanoma, 2020Co-Authors: Guido Massi, Philip E LeboitAbstract:In 1978 Clark and his colleagues put forth a hypothesis that still provokes controversy — the idea that a set of findings in nevi of members of families with a tendency to develop melanoma was a clinicopathologic entity, representing an intermediate step between the “common Nevus” and melanoma. The dysplastic Nevus is still a controversial entity with some specific clinical and histological characteristics, but with “fuzzy” borders. The dividing line between a “common Nevus” at the lower end and melanoma in situ or superficially invasive melanoma at the upper end defies precise characterization, similar to that in other “intermediate” lesions in pathology.
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Nevus Spilus (Speckled lentiginous Nevus)
Histological Diagnosis of Nevi and Melanoma, 2020Co-Authors: Guido Massi, Philip E LeboitAbstract:We define Nevus spilus as a medium-sized, or large, cafe au lait macule speckled with melanocytic nevi. The definition is incorrect and imprecise but it is very entrenched in the common dermatological jargon and it is less cumbersome than others which are nosologically more appropriate. The French literature refers to this entity as “Nevus en Nevus”.
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Clark Nevus and Dysplastic Nevus
Histological Diagnosis of Nevi and Melanoma, 2014Co-Authors: Guido Massi, Philip E LeboitAbstract:1978, Wallace Clark and his colleagues set forth a hypothesis that still has some controversial aspects – the idea that a set of fi ndings in nevi of members of families with a tendency to develop melanoma comprise a clinicopathological entity, representing an intermediate step between the “common Nevus” and melanoma. While few would dispute that the clinical phenotype of many large, atypical appearing nevi is a marker for an increased risk of melanoma and tends to be inherited, many of the melanomas in these patients arise de novo rather than in preexistent lesions. Just how distinctive these nevi are and whether they pose a risk for the development of melanoma within the lesions themselves that is different from that of other nevi are still debated. Clark and his colleagues coined the term dysplastic Nevus to highlight their belief that the lesions in question were partially transformed neoplasms, within the same realm of precancerous alterations found in other organs.
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Halo Nevus (Regressing Nevus)
Histological Diagnosis of Nevi and Melanoma, 2013Co-Authors: Guido Massi, Philip E LeboitAbstract:Histologically, the so-called halo Nevus is overwhelmed by an infl ammatory, mostly lymphocytic infi ltrate with extensive loss of melanocytes. The clinically evident white halo corresponds to the loss of melanin in the basal layer of the epidermis and to a reduction in the number of melanocytes.
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Blue Nevus(“Common” blue Nevus)
Histological Diagnosis of Nevi and Melanoma, 2004Co-Authors: Guido Massi, Philip E LeboitAbstract:The “common” blue Nevus, is a benign neoplasm composed of dendritic melanocytes accompanied by numerous melanophages. The lesion is entirely contained in the dermis, without a junctional component. The common blue Nevus constitutes a clinical and morphological continuum with the so called “cellular” blue Nevus, discussed in the next chapter. The dichotomy, common versus cellular is entrenched in literature, but ignores the great variety of appearances that blue nevi have.
Beth S Ruben - One of the best experts on this subject based on the ideXlab platform.
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widespread porokeratotic adnexal ostial Nevus clinical features and proposal of a new name unifying porokeratotic eccrine ostial and dermal duct Nevus and porokeratotic eccrine and hair follicle Nevus
Journal of The American Academy of Dermatology, 2009Co-Authors: Deborah S Goddard, Maureen Rogers, Ilona J Frieden, Alfons Krol, Clifton R White, Anu G Jayaraman, Leslie Robinsonbostom, Anna L Bruckner, Beth S RubenAbstract:Porokeratotic eccrine ostial and dermal duct Nevus and a similar condition, porokeratotic eccrine and hair follicle Nevus, are rare disorders of keratinization with eccrine and hair follicle involvement. We describe the clinical features in 5 patients, all of whom had widespread skin involvement following the lines of Blaschko. Two patients presented with erosions in the newborn period as the initial manifestation of their disease; one had an associated structural anomaly, unilateral breast hypoplasia; and one adult had malignant transformation in the Nevus with development of multifocal squamous cell carcinomas. Three patients had histologic involvement of both acrosyringia and acrotrichia. Based on the observation of overlapping histologic features, we propose the name "porokeratotic adnexal ostial Nevus" to incorporate the previously described entities porokeratotic eccrine ostial and dermal duct Nevus and porokeratotic eccrine and hair follicle Nevus.
Deborah S Goddard - One of the best experts on this subject based on the ideXlab platform.
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widespread porokeratotic adnexal ostial Nevus clinical features and proposal of a new name unifying porokeratotic eccrine ostial and dermal duct Nevus and porokeratotic eccrine and hair follicle Nevus
Journal of The American Academy of Dermatology, 2009Co-Authors: Deborah S Goddard, Maureen Rogers, Ilona J Frieden, Alfons Krol, Clifton R White, Anu G Jayaraman, Leslie Robinsonbostom, Anna L Bruckner, Beth S RubenAbstract:Porokeratotic eccrine ostial and dermal duct Nevus and a similar condition, porokeratotic eccrine and hair follicle Nevus, are rare disorders of keratinization with eccrine and hair follicle involvement. We describe the clinical features in 5 patients, all of whom had widespread skin involvement following the lines of Blaschko. Two patients presented with erosions in the newborn period as the initial manifestation of their disease; one had an associated structural anomaly, unilateral breast hypoplasia; and one adult had malignant transformation in the Nevus with development of multifocal squamous cell carcinomas. Three patients had histologic involvement of both acrosyringia and acrotrichia. Based on the observation of overlapping histologic features, we propose the name "porokeratotic adnexal ostial Nevus" to incorporate the previously described entities porokeratotic eccrine ostial and dermal duct Nevus and porokeratotic eccrine and hair follicle Nevus.
