[Cutaneous Manifestations in Mastocytosis: Update]. / Manifestações Cutâneas nas Mastocitoses: Atualização.

INTRODUCTION: Mastocytosis is characterized by the clonal expansion of morphological and immunophenotypically abnormal mast cells in different organs. The skin is the most frequently affected tissue. Virtually all children and more than 80% of adult patients with mastocytosis show cutaneous lesions. MATERIAL AND METHODS: The present article describes the symptoms and signs in cutaneous mastocytosis, based on the review of recently published international consensus guidelines. DISCUSSION: According to the 2016 World Health Organization classification, mastocytosis can be divided in cutaneous mastocytosis, systemic mastocytosis and mast cell sarcoma. Cutaneous mastocytosis is subclassified in three subtypes: maculopapular cutaneous mastocytosis, diffuse cutaneous mastocytosis and cutaneous astocytoma. Telangiectasia macularis eruptiva perstans is no longer considered a distinct entity. CONCLUSION: Based on the age of onset, cutaneous manifestations of mastocytosis can be variable. The classification of cutaneous mastocytosis has recently been updated. Typically, in patients with childhood-onset mastocytosis, the disease occurs as cutaneous mastocytosis and shows spontaneous resolution around puberty. In contrast, adult patients, despite having also cutaneous lesions, often show systemic involvement and the course of the disease is usually chronic.

Introdução: As mastocitoses caraterizam-se pela expansão clonal de mastócitos, com acumulação de mastócitos morfológica e imunofenotipicamente anormais em diferentes órgãos. A pele é o órgão mais frequentemente envolvido. Virtualmente, todas as crianças e mais de 80% dos adultos com mastocitose apresentam lesões cutâneas.Material e Métodos: O presente artigo descreve os sinais e sintomas associados à mastocitose na pele, tendo por base a revisão das normas de orientação de consenso internacionais, recentemente publicadas.Discussão: De acordo com a classificação proposta pela Organização Mundial de Saúde em 2016, a mastocitose divide-se em mastocitose cutânea, mastocitose sistémica e sarcoma de mastócitos. A mastocitose cutânea pode subdividir-se em três subtipos: a mastocitose cutânea maculopapular (também denominada urticária pigmentosa), mastocitose cutânea difusa e mastocitoma cutâneo. A telangiectasia macular eruptiva perstans já não é considerada uma entidade independente.Conclusão: As manifestações cutâneas da mastocitose são variáveis, dependendo da idade de início da doença. Recentemente a classificação da mastocitose cutânea foi atualizada. Nas crianças, a mastocitose ocorre como mastocitose cutânea que tende à regressão espontânea durante a adolescência. Quando tem início na idade adulta, a mastocitose é geralmente sistémica, sendo a forma mais frequente a mastocitose sistémica indolente, que normalmente também cursa com manifestações cutâneas e tem um curso crónico.

[Cutaneous mastocytosis - update and clinical guidelines]. / Mastocytos i huden ­ uppdatering av kunskapsläget och riktlinjer för handläggning.

Mastocytosis is a rare and multifaceted disease group characterized by mast cell accumulation in the skin and/or internal organs. In its most common form solitary or widespread, often itchy, red-brown skin lesions appear in childhood or during adulthood (cutaneous mastocytosis). The skin lesions are not always easy to recognize by medical professionals; hence, a correct diagnosis is often delayed. In children, the lesions tend to resolve before puberty, whereas most post-adolescent patients experience a chronic course combined with extra-cutaneous mast cell infiltration (systemic mastocytosis). Therefore, adult patients with cutaneous mastocytosis should be examined for signs of systemic involvement. This article describes the symptoms and signs in cutaneous mastocytosis, and provides guidelines based on international consensus documents. In addition, a newly updated classification of different forms of cutaneous mastocytosis is given.

Assessment of Canine Mast Cell Tumor Mortality Risk Based on Clinical, Histologic, Immunohistochemical, and Molecular Features.

Mast cell tumor (MCT) is a frequent cutaneous neoplasm in dogs that is heterogeneous in clinical presentation and biological behavior, with a variable potential for recurrence and metastasis. Accurate prediction of clinical outcomes has been challenging. The study objective was to develop a system for classification of canine MCT according to the mortality risk based on individual assessment of clinical, histologic, immunohistochemical, and molecular features. The study included 149 dogs with a histologic diagnosis of cutaneous or subcutaneous MCT. By univariate analysis, MCT metastasis and related death was significantly associated with clinical stage ( P < .0001, rP = -0.610), history of tumor recurrence ( P < .0001, rP = -0.550), Patnaik ( P < .0001, rP = -0.380) and Kiupel grades ( P < .0001, rP = -0.500), predominant organization of neoplastic cells ( P < .0001, rP = -0.452), mitotic count ( P < .0001, rP = -0.325), Ki-67 labeling index ( P < .0001, rP = -0.414), KITr pattern ( P = .02, rP = 0.207), and c-KIT mutational status ( P < .0001, rP = -0.356). By multivariate analysis with Cox proportional hazard model, only 2 features were independent predictors of overall survival: an amendment of the World Health Organization clinical staging system (hazard ratio [95% CI]: 1.824 [1.210-4.481]; P = .01) and a history of tumor recurrence (hazard ratio [95% CI]: 9.250 [2.158-23.268]; P < .001]. From these results, we propose an amendment of the WHO staging system, a method of risk analysis, and a suggested approach to clinical and laboratory evaluation of dogs with cutaneous MCT.

Telangiectasia macularis eruptiva perstans: an old terminology, still frequently used.

The term telangiectasia macularis eruptiva perstans (TMEP) was originally used to describe a rare form of cutaneous mastocytosis (CM) that was limited to the skin with lesions consisting of irregular, telangiectatic macules ranging in color from red to brown. Recent guidelines, however, recommended that the sole presence of telangiectasias should not form the basis of a distinct variant of CM. We conducted a review of the literature from 1930 to 2017 and found 76 cases that were reported as TMEP. Owing to a general misconception about diagnosis of CM and SM, there is a need for further discussion and awareness of the newly proposed World Health Organization (WHO) guidelines.

Cutaneous manifestations in patients with mastocytosis: Consensus report of the European Competence Network on Mastocytosis; the American Academy of Allergy, Asthma & Immunology; and the European Academy of Allergology and Clinical Immunology.

Cutaneous lesions in patients with mastocytosis are highly heterogeneous and encompass localized and disseminated forms. Although a classification and criteria for cutaneous mastocytosis (CM) have been proposed, there remains a need to better define subforms of cutaneous manifestations in patients with mastocytosis. To address this unmet need, an international task force involving experts from different organizations (including the European Competence Network on Mastocytosis; the American Academy of Allergy, Asthma & Immunology; and the European Academy of Allergology and Clinical Immunology) met several times between 2010 and 2014 to discuss the classification and criteria for diagnosis of cutaneous manifestations in patients with mastocytosis. This article provides the major outcomes of these meetings and a proposal for a revised definition and criteria. In particular, we recommend that the typical maculopapular cutaneous lesions (urticaria pigmentosa) should be subdivided into 2 variants, namely a monomorphic variant with small maculopapular lesions, which is typically seen in adult patients, and a polymorphic variant with larger lesions of variable size and shape, which is typically seen in pediatric patients. Clinical observations suggest that the monomorphic variant, if it develops in children, often persists into adulthood, whereas the polymorphic variant may resolve around puberty. This delineation might have important prognostic implications, and its implementation in diagnostic algorithms and future mastocytosis classifications is recommended. Refinements are also suggested for the diagnostic criteria of CM, removal of telangiectasia macularis eruptiva perstans from the current classification of CM, and removal of the adjunct solitary from the term solitary mastocytoma.

Coexistence of two types of clinical lesions in childhood-onset mastocytosis.

The vast majority of mastocytosis appear in childhood, urticaria pigmentosa (UP) and mastocytomas being the most common types. Terms such as "xanthelasmoid mastocytosis", "pseudoxanthomatous mastocytosis" or "nodular mastocytosis" have been introduced in the literature to describe the presence of yellowish papular or nodular lesions. We describe two children with cutaneous mastocytosis showing yellowish lesions in combination with other skin lesions. A 10-year-old girl presented with asymptomatic lesions in her vulva at birth, and developed brownish macules on her trunk years after. An eight-year-old boy presented with multiple yellowish papular lesions on his trunk, neck and limbs coexisting with a few clinically anetodermic lesions. No systemic involvement was found and the skin biopsy confirmed a cutaneous mastocytosis in both cases. The two patients are currently asymptomatic and are being periodically followed up. Mastocytoses may show a variety of clinical lesions, sometimes leading to misdiagnosis. Although there are previous reports, involvement of the mucosae and secondary anetoderma are not common findings in cutaneous mastocytoses. We consider that cutaneous manifestations of mastocytoses compose a clinical spectrum, thus explaining the coexistence of different clinical lesions and the development of uncommon presentations.

Mastocitosis cutánea: revisión de 10 años de experiencia en el Servicio de Dermatología del Hospital General de Niños Pedro de Elizalde / Cutaneous mastocytosis: 10-years experience review at the Dermatology Department, Hospital General de Niños Pedro de Elizalde

Introducción. La mastocitosis representa un espectro de trastornos clínicos con un fenotipo común correspondiente a una hiperplasia de los mastocitos tisulares. Objetivo. Presentar la experiencia del Servicio de Dermatología del Hospital General de Niños Pedro de Elizalde en mastocitosis cutánea en los últimos 10 años. Diseño. Estudio retrospectivo y descriptivo, de corte transversal. Material y método. Se revisaron los archivos histológicos correspondientes al período que va de marzo de 1999 a marzo de 2099 del Servicio de Dermatología del Hospital General de Niños Pedro de Elizalde. Se consideraron como variables de estudio la edad al momento de la consulta, sexo, presencia de antecedentes personales y familiares, tipo clínico, localización, presencia de síntomas al examen físico, así como hallazos patológicos en los estudios complementarios. Los resultados se expresaron en promedios y porcentajes. Resultados. Presentamos 49 casos con diagnóstico clínico e histológico de mastocitosis cutánea; 33 pacientes (67,3%) de sexo masculino y 16 (32,7%) de sexo femenino. En cuanto al tipo clínico de mastocitosis, se encontraron 36 casos de urticaria pigmentosa (73,4%), 6 casos de mastocitoma solitario (12,2%), 5 casos de telangiectasia macularis eruptiva perstans (10,2%) y 2 casos donde coexistía mastocitoma solitario y urticaria pigmentosa (4%). No se encontraron casos de mastocitosis cutánea difusa. Las lesiones se distribuyen en tronco 25 casos (51%), en tronco y miembros 17 casos (34,6%), en cabeza, tronco y miembros 3 casos (6,1%), en miembros 3 casos (6,1%), en cabeza y tronco un caso (2,04%). Conclusión. En nuestra casuística, la manifestación clínica más frecuente fue la urticaria pigmentosa, similar a lo señalado en la bibliografía. Encontramos, a diferencia de lo publicado en la literatura, un predominio de sexo masculino y un alto porcentaje (10,2%) de pacientes pediátricos con la forma de telangiectasia macularis eruptiva perstans.

IntroductionMastocytosis represents a spectrum of clinical disorders with a common phenotype correspondingto hyperplasia of mast cells on tissues.ObjectiveTo present the experience of the Department of Dermatology, Hospital General de Niños Pedro deElizalde in cutaneous mastocytosis during the past 10 years.DesignRetrospective and descriptive, cross sectional study.Material and methodsHistological records were reviewed for the period March 1999-March 2009 at the Department ofDermatology, Hospital General de Niños Pedro de Elizalde.The variables considered were: age at time of consultation, gender, presence of personal andfamily history, clinical type, location, presence of symptoms by physical examination andabnormal findings on complementary studies.The results were expressed as averages and percentages.ResultsForty nine patients with clinical and histological diagnosis of cutaneous mastocytosis arepresented, 33 of them were male (67.3%) and 16 were female (32.7%).As regards to the clinical type of mastocytosis, 36 patients presented urticaria pigmentosa(73.4%), 6 had solitary mastocytoma (12.2%), 5 presented telagiectasia macularis eruptivaperstans (10.2%) and 2 patients presented solitary mastocytoma combined with urticariapigmentosa (4%). Diffuse cutaneous mastocytosis was not found.Twenty five patients had lesions distributed on the trunk (51%), trunk and limbs on 17 (34.6%),head, trunk and limbs 3 patients (6.1%), on limbs only 3 patients (6.1%), while head and trunktogether were affected on 1 patient (2.04%).ConclusionIn our caseload, the most frequent clinical manifestation was urticaria pigmentosa, similar tofindings in the literature.As opposed to published data we found predominance in males, and a high incidence (10.2%)of pediatric patients with telangiectasia macularis eruptiva perstans.

Mastocitosis en edad pediátrica / Mastocytosis in children

Las mastocitosis incluyen un amplio espectro de patologías que tienen en común la infiltración anormal de mastocitos en diversos órganos, siendo la piel el más frecuentemente comprometido. Se reconocen dos variantes principales de la enfermedad: la mastocitosis cutánea (MC), que sólo compromete la piel, y la mastocítosis sistémica (M S), donde hay compromiso de órganos extracutáneos. La sintomatología de ambas variantes es causada por la infiltración celular y daño directo sobre los tejidos, así como por la liberación de mediadores químicos a la circulación sistémica, lo que hace que su presentación clínica sea altamente variable. Las mastocitosis en niños se presentan generalmente como MC, son de buen pronóstico y evolucionan con remisión de las lesiones en la mayoría de los casos. Las MS son muy poco frecuentes en este grupo etario; sin embargo, su curso crónico y la agresividad que pueden adquirir ponen en relieve la importancia de considerarlas en el diagnóstico diferencial de estos cuadros. En la actualidad no existe tratamiento curativo para las mastocitosis y el manejo es fundamentalmente sintomático.

Mastocytosis is a heterogeneous group of diseases characterized by the abnormal infiltration of mast cells (MCs) in one or more organ systems, being the skin the most common organ affected. Two main variants of the disease are recognized: cutaneous mastocytosis (CM), if abnormal infiltrates are confined to the skin, and systemic mastocytosis (SM) , if extra-cutaneous tissues are involved. Symptoms are extremely variable and result from MC-derived mediators and from destructive infiltration of MCs. The typical presentation of pediatric-onset mastocytosis consists of cutaneous manifestations, and usually regresses spontaneously. SM is a chronic disease with variable clinical course ranging from asymptomatic to highly aggressive and rapidly devastating. SM is rare in children but should be considered in the differential diagnosis. No curative treatment has been yet reported for mastocytosis and only symptomatic therapy is available.

Clinical aspects of diffuse cutaneous mastocytosis in children: two variants.

OBJECTIVE: This paper describes two different clinical presentations of diffuse cutaneous mastocytosis (DCM), based on the largest series published to date. As far as we are aware, these two variants of clinical presentations have not yet been reported. DESIGN: We undertook a case controlled analysis of 8 children with DCM. Results of laboratory testing including mast cell mediator levels, and clinical symptoms on presentation and during follow-up were analyzed. RESULTS: The levels of relevant mast cell mediators were initially high in all cases but declined sharply later on. There was a reduction of 20% in 2 of the 7 cases, whereas there was a reduction of 80% in the remaining 5. No reduction occurred in 1 case. Clinical improvement followed the same pattern. CONCLUSIONS: DCM is a rare variant of cutaneous childhood onset mastocytosis. Various forms show the same or overlapping features at various times. It appears to follow a course similar to that in other types of childhood onset mastocytosis, taking into account the decreased symptoms and the levels of mast cell mediators during follow-up. Obtaining a bone marrow biopsy should be considered only in those cases where there is no improvement or even worsening of signs or symptoms and persistent elevated levels of mast cell mediators.

Cutaneous mastocytosis: a review focusing on the pediatric population.

Cutaneous mastocytosis can be divided into 4 different clinical variants--urticaria pigmentosa, solitary mastocytoma, diffuse cutaneous mastocytosis, and telangiectasia macularis eruptiva perstans. Skin findings are often accompanied by symptoms secondary to mast cell release of mediators. These symptoms can be both localized to the skin lesion and systemic because of the release of mediators into the bloodstream. The majority of pediatric cases of cutaneous mastocytosis show a good prognosis with gradual resolution of both symptoms and skin lesions. This article will review each of the 4 clinical presentations focusing on pediatric-onset of disease while reviewing the literature.

Cutaneous mastocytosis: demographic aspects and clinical features of 55 patients.

BACKGROUND: Mastocytosis is a rare, heterogeneous group of disorder with abnormal increase of mast cells in one or more organ systems. OBJECTIVE: To evaluate the demographic and clinical features of cutaneous mastocytosis (CM). METHODS: Records of 55 patients with cutaneous mastocytosis were retrospectively analysed. RESULTS: Of the 22 females and 33 males, 80% had urticaria pigmentosa/maculopapular CM and 20% had mastocytoma. Of all cases, 81.8% had first lesions in childhood. The most common presentation was involvement of trunk together with extremities. Thirteen (23.6%) patients had history of bulla; Darier's sign was positive in 34 of 38 patients. Itching was the most common complaint, provocated by hot weather/bath. CONCLUSION: Clinical presentations of urticaria pigmentosa/maculopapular CM and mastocytoma are similar regarding gender, age of onset, age of diagnosis, and presence of Darier's sign and history of bulla. In contrast to mastocytoma, urticaria pigmentosa/maculopapular CM lesions were frequently located on trunk together with extremities.

Variation among pathologists in the histologic grading of canine cutaneous mast cell tumors with uniform use of a single grading reference.

Ten veterinary pathologists independently assigned histologic grades to the same 60 canine cutaneous mast cell tumors using the Patnaik classifications. The degree of agreement in grading among the pathologists was compared with the degree of agreement among the same pathologists in a previous study, in which each pathologist used the reference for grading that he/she uses routinely. Mean agreement improved significantly from 50.3% to 62.1% with uniform use of the Patnaik classifications (P = 0.00001), suggesting that there is value in uniform application of a single grading scheme for canine cutaneous mast cell tumors. Agreement among pathologists was still not 100%, suggesting that a more objective grading scheme should be developed and that other histologic indicators of prognosis should be investigated.

Mast cell proliferative disorders: current view on variants recognized by the World Health Organization.

The term mastocytosis covers a heterogeneous group of disorders characterized by the abnormal growth and accumulation of MCs in one or more organ systems. Clinical symptoms occur from the release of chemical mediators or pathologic infiltration of MCs. CM typically presents as UP and is a benign disease confined to the skin. In many cases, particularly in children, this disease regresses spontaneously. By contrast, SM is a clonal persistent disease of MC-committed or precommitted hematopoietic progenitors. In most of these patients, the transforming c-kit mutation Asp-816-Val is detectable. The clinical course in SM is variable. Many cases remain in an indolent stage over decades. In a few patients, significant organopathy is found, and this may lead to the diagnosis of aggressive SM. In other patients, AHNMD is diagnosed. MCL is a rare form of SM characterized by leukemic spread of MCs in the marrow and blood and rapid progression. In contrast to indolent SM, patients with MCL or aggressive SM often present without UP-like skin lesions. Patients with indolent SM should be treated with mediator-targeting drugs but not with cytoreductive drugs. By contrast, patients with aggressive SM or MCL are candidates for cytoreductive therapy. Some patients with aggressive SM may benefit from IFNalpha2b. Patients with rapid progression or MCL are candidates for more aggressive treatment, including cladribine, chemotherapy, and stem cell transplantation. In patients with SM-AHNMD, the SM should be treated as if no AHNMD is present, and the AHNMD should be treated as if no SM had been diagnosed.