RESUMO
Since the publication of the Revised European-American Classification of Lymphoid Neoplasms in 1994, subsequent updates of the classification of lymphoid neoplasms have been generated through iterative international efforts to achieve broad consensus among hematopathologists, geneticists, molecular scientists, and clinicians. Significant progress has recently been made in the characterization of malignancies of the immune system, with many new insights provided by genomic studies. They have led to this proposal. We have followed the same process that was successfully used for the third and fourth editions of the World Health Organization Classification of Hematologic Neoplasms. The definition, recommended studies, and criteria for the diagnosis of many entities have been extensively refined. Some categories considered provisional have now been upgraded to definite entities. Terminology for some diseases has been revised to adapt nomenclature to the current knowledge of their biology, but these modifications have been restricted to well-justified situations. Major findings from recent genomic studies have impacted the conceptual framework and diagnostic criteria for many disease entities. These changes will have an impact on optimal clinical management. The conclusions of this work are summarized in this report as the proposed International Consensus Classification of mature lymphoid, histiocytic, and dendritic cell tumors.
Assuntos
Neoplasias Hematológicas , Linfoma , Comitês Consultivos , Consenso , Neoplasias Hematológicas/diagnóstico , Neoplasias Hematológicas/genética , Humanos , Linfoma/patologia , Organização Mundial da SaúdeRESUMO
Primary cutaneous B-cell lymphomas (PCBCLs) are lymphoproliferative disorders that appear on the skin without evidence of extracutaneous manifestations at the time of diagnosis. There is a lack of evidence-based guidelines for their clinical management due to the availability of very few large scale studies and controlled clinical trials. Here we present and discuss a series of major unmet clinical needs (UCNs) in the management of PCBCLs by a panel of 16 experts involved in research and clinical practice of PCBCL. The Panel produced recommendations on the appropriateness of the clinical decisions concerning the identified clinical needs and proposed research for improving the knowledge needed to solve them. Recommendations and proposals were achieved by multiple-step formalized procedures to reach a consensus after a comprehensive analysis of the scientific literature. Recommendations and proposals lay in the domain of classification uncertainties of PCBCL, optimization of diagnosis, optimization of prognosis, optimization of staging and critical issues on therapeutic strategies with particular focus on new treatments. These recommendations are intended for use not only by experts but above all by dermatologists and hematologists with limited experience in the field of PCBCLs as well as general practitioners.
Assuntos
Linfoma de Células B , Neoplasias Cutâneas , Humanos , Linfoma de Células B/diagnóstico , Linfoma de Células B/terapia , Linfoma de Células B/patologia , Consenso , Neoplasias Cutâneas/diagnóstico , Neoplasias Cutâneas/terapia , Neoplasias Cutâneas/patologia , PrognósticoRESUMO
ABSTRACT: Lichen myxedematosus (LM) is an uncommon cutaneous mucinosis characterized by the deposition of mucin and fibroblast proliferation in the dermis. This condition can be classified into 2 forms: a diffuse/generalized LM, also known as scleromyxedema, associated with monoclonal gammopathy and systemic implications, and a localized form, primarily affecting the skin. Within the localized form, nodular-type LM is a rare variant presenting as firm, skin-colored to pinkish mucinous nodules. In this article, we report 2 new cases of nodular-type LM with exclusive involvement of the hands and provide a comprehensive review of the diagnosis, histopathological aspects, and therapeutic considerations of this rare condition.
Assuntos
Escleromixedema , Dermatopatias , Humanos , Escleromixedema/diagnóstico , Escleromixedema/patologia , Pele/patologia , Dermatopatias/patologia , Mãos/patologia , Extremidade Superior/patologiaRESUMO
ABSTRACT: A 38-year-old man presented with fever, cough, and jaundice. Four days before, he had started taking amoxicillin/clavulanic acid. He subsequently developed a morbilliform rash, and, according to clinical features and blood analyses, a diagnosis of mononucleosis with Epstein-Barr virus-associated antibiotic-induced exanthema and secondary hemophagocytic lymphohistiocytosis was made. A skin biopsy revealed a superficial perivascular lymphohistiocytic infiltrate with interface dermatitis and many foamy macrophages in the papillary dermis and around the vessels of the superficial dermal plexus. A blood lipid test uncovered marked hypercholesterolemia and hypertriglyceridemia. After treatment with dexamethasone and immunoglobulin, the skin rash, liver function, and lipid profile progressively improved. Xanthomatous cells have been observed in skin biopsies of acute graft-versus-host disease with liver involvement, and these cells have been suggested to represent a clue to the presence of hepatic disease. In our case, underlying cholestatic hepatopathy with hyperlipidemia was present. We believe that the incidental finding of foamy cells in graft-versus-host disease cases and in our case are likely related to the presence of severe liver disease with cholestatic hepatopathy and secondary hyperlipidemia in different background conditions.
Assuntos
Infecções por Vírus Epstein-Barr , Exantema , Doença Enxerto-Hospedeiro , Hiperlipidemias , Linfo-Histiocitose Hemofagocítica , Masculino , Humanos , Adulto , Linfo-Histiocitose Hemofagocítica/patologia , Infecções por Vírus Epstein-Barr/complicações , Hiperlipidemias/induzido quimicamente , Hiperlipidemias/complicações , Herpesvirus Humano 4 , Amoxicilina , Exantema/induzido quimicamente , Exantema/complicações , Lipídeos , Macrófagos/patologiaRESUMO
BACKGROUND: There is considerable variation in the literature regarding the dermatopathologic diagnostic features of and reporting guidelines for actinic keratosis (AK) and cutaneous squamous cell carcinoma (cSCC). OBJECTIVE: To develop consensus recommendations regarding diagnostic criteria, nomenclature, and reporting of AK and cSCC. METHODS: Literature review and cross-sectional multiround Delphi process including an international group of expert dermatopathologists followed by a consensus meeting. RESULTS: Consensus was achieved regarding the key dermatopathologic features necessary for diagnosing cSCC, AK, and associated variants; grading of degree of cellular differentiation in cSCC; utility of immunohistochemistry for diagnosis of cSCC; and pathologic features that should be reported for cSCC and AK. LIMITATIONS: Consensus was not achieved on all questions considered. CONCLUSION: Despite the lack of clarity in the literature, there is consensus among expert dermatopathologists regarding diagnostic criteria and appropriate reporting of AK and cSCC. Widespread implementation of these consensus recommendations may improve communication between dermatopathologists and clinicians, facilitating appropriate treatment of AK and cSCC.
Assuntos
Carcinoma de Células Escamosas , Ceratose Actínica , Neoplasias Cutâneas , Humanos , Carcinoma de Células Escamosas/diagnóstico , Carcinoma de Células Escamosas/patologia , Consenso , Estudos Transversais , Ceratose Actínica/patologia , Neoplasias Cutâneas/diagnóstico , Neoplasias Cutâneas/patologiaRESUMO
Essential thrombocythemia is a chronic myeloproliferative syndrome which usually runs its course as an asymptomatic elevated platelet count. Cutaneous manifestations secondary to microcirculation abnormalities are rare but can represent a helpful diagnostic clue in order to prevent major thromboembolic events. We report two cases of heterogeneous livedoid and "net-like" skin lesions in the context of essential thrombocythemia with identical histopathologic findings (medium-sized blood vessels with luminal obliteration by eosinophilic material, mostly positive for the platelet marker CD61, without vasculitis). In conclusion, we seek to raise awareness of the clinicopathological features of essential thrombocythemia to allow for prompt diagnosis and treatment.
Assuntos
Dermatopatias , Trombocitemia Essencial , Humanos , Trombocitemia Essencial/complicações , Trombocitemia Essencial/diagnóstico , Trombocitemia Essencial/patologia , Dermatopatias/complicaçõesRESUMO
BACKGROUND: Mycosis fungoides is rarely associated to B-cell malignancies, and the few reported cases are mainly internal lymphomas involving secondarily the skin (ie, chronic lymphocytic leukemia). OBJECTIVES: The aim of our study is to describe the clinical and histopathological features of 4 patients presenting with 2 concurrent primary cutaneous lymphomas and review the pertinent literature. METHODS: We identified 4 cases of concurrent primary cutaneous lymphomas in our institutions. An extracutaneous lymphoma was ruled out on the basis of a complete work out. We performed a PubMed search to identify reported cases of primary cutaneous composite or concurrent lymphomas. RESULTS: Eleven cases of primary cutaneous concurrent lymphomas have been described in the literature. Counting all together (our cases and the cases previously described in the literature), mycosis fungoides was the most frequent primary cutaneous T-cell lymphoma (TCL) (13/15), followed by 1 case of peripheral TCL-NOS and 1 case of subcutaneous panniculitis-like TCL. Regarding the associated primary cutaneous B-cell lymphomas, 8/15 cases consisted of low-grade B-cell lymphomas [that is, 5 marginal zone lymphoma (in the most recent classification reclassified as marginal zone lymphoproliferative disorder, MZLD, 2 follicular-center B-cell lymphoma (primary cutaneous follicle-center lymphoma) and 1 low-grade NOS B-cell lymphoma]; 4/15 were associated to Epstein-Barr virus; 1 case consisted of a methotrexate-associated lymphoproliferative disease, and 2 cases consisted of primary cutaneous diffuse large B-cell lymphoma-leg type. CONCLUSIONS: Primary cutaneous concurrent lymphomas are exceptional. Clinicopathological correlation and a complete workout to reach the correct diagnosis may guide the appropriate treatment in each case.
Assuntos
Infecções por Vírus Epstein-Barr , Linfoma de Zona Marginal Tipo Células B , Linfoma Cutâneo de Células T , Micose Fungoide , Neoplasias Cutâneas , Humanos , Neoplasias Cutâneas/patologia , Herpesvirus Humano 4 , Micose Fungoide/patologia , Linfoma Cutâneo de Células T/patologiaRESUMO
BACKGROUND: The differential diagnosis of atypical dermal nonepidermotropic CD8+ lymphocytic infiltrates includes a heterogeneous spectrum of lymphoproliferations with overlapping histological and phenotypic features, but divergent clinical manifestations and prognoses. As these neoplasms are rare, more data on their clinicopathological presentation and course are needed. OBJECTIVES: To assess the clinical, histological and immunophenotypic features; outcomes of; and differences between dermal CD8+ lymphoproliferations. METHODS: Retrospective analysis of a series of 46 patients and biopsies by the international EORTC Cutaneous Lymphoma Group. RESULTS: The dermal CD8+ lymphoproliferations (n = 46) could be assigned to one of three groups: (i) cutaneous acral CD8+ T-cell lymphoma (n = 31), characterized mostly by a solitary nodule arising at acral sites, a monotonous dermal infiltrate of small-to-medium-sized CD8+ lymphocytes with a characteristic dot-like pattern of CD68, a low proliferation rate and an excellent prognosis; (ii) primary cutaneous CD8+ peripheral T-cell lymphoma, unspecified/NOS (n = 11), presenting with one or multiple rapidly evolving tumours, mostly medium-sized pleomorphic CD8+ tumour cells with expression of several cytotoxic markers, and high proliferative activity; and (iii) cutaneous CD8+ lymphoproliferations (n = 4), associated with congenital immunodeficiency syndromes in two patients with persisting localized or disseminated violaceous to brownish plaques on the extremities, a histiocyte-rich infiltrate of mostly small CD8+ lymphocytes with subtle atypia and a protracted course; and papular CD8+ eruptions in two patients with acquired immunosuppression. CONCLUSIONS: A constellation of distinct clinical, histopathological and phenotypic features allows discrimination and assignment of dermal CD8+ infiltrates into distinct disease entities. Primary cutaneous acral CD8+ lymphoma, assigned a provisional category in current lymphoma classifications, is a distinct and reproducible entity. A correct diagnosis is essential to avoid unnecessarily aggressive treatment for indolent CD8+ lymphoproliferations and to identify cases with underlying immuno-deficiency or potential for dismal outcome.
Assuntos
Linfoma Cutâneo de Células T , Neoplasias Cutâneas , Linfócitos T CD8-Positivos/patologia , Humanos , Linfoma Cutâneo de Células T/diagnóstico , Linfoma Cutâneo de Células T/patologia , Prognóstico , Estudos Retrospectivos , Neoplasias Cutâneas/patologiaRESUMO
ABSTRACT: The presence of neoplastic melanocytes within the eccrine apparatus into the reticular dermis and/or subcutaneous tissue is extremely rare. The staging of syringotropic melanomas and their biological behavior are still controversial. We present 6 new cases of syringotropic melanoma and their main histopathologic features; review the previous literature; and discuss about the origin, staging, and prognosis of this rare variant of melanoma.
Assuntos
Melanócitos/patologia , Melanoma/patologia , Neoplasias Cutâneas/patologia , Glândulas Sudoríparas/patologia , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/análise , Biópsia , Diagnóstico Diferencial , Feminino , Humanos , Imuno-Histoquímica , Masculino , Melanócitos/química , Melanoma/química , Melanoma/cirurgia , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Neoplasias Cutâneas/química , Neoplasias Cutâneas/cirurgia , Glândulas Sudoríparas/química , Glândulas Sudoríparas/cirurgia , Resultado do TratamentoRESUMO
Primary cutaneous lymphomas are a heterogeneous group of T- and B-cell lymphomas that present in the skin with no evidence of extracutaneous disease at the time of diagnosis. The 2005 World Health Organization-European Organization for Research and Treatment of Cancer (WHO-EORTC) consensus classification has served as a golden standard for the diagnosis and classification of these conditions. In September 2018, an updated version of the WHO-EORTC was published in the fourth edition of the WHO Classification of Skin Tumours Blue Book. In this classification, primary cutaneous acral CD8+ T-cell lymphoma and Epstein-Barr virus positive (EBV+) mucocutaneous ulcer are included as new provisional entities, and a new section on cutaneous forms of chronic active EBV disease has been added. The term "primary cutaneous CD4+ small/medium T-cell lymphoma" was modified to "primary cutaneous CD4+ small/medium T-cell lymphoproliferative disorder" because of its indolent clinical behavior and uncertain malignant potential. Modifications have also been made in the sections on lymphomatoid papulosis, increasing the spectrum of histologic and genetic types, and primary cutaneous marginal zone lymphomas recognizing 2 different subtypes. Herein, the characteristic features of these new and modified entities as well as the results of recent molecular studies with diagnostic, prognostic, and/or therapeutic significance for the different types of primary cutaneous lymphomas are reviewed. An update of the frequency and survival of the different types of primary cutaneous lymphomas is provided.
Assuntos
Linfoma Cutâneo de Células T/classificação , Neoplasias Cutâneas/classificação , Herpesvirus Humano 4 , Humanos , Linfoma de Células B , Linfoma Cutâneo de Células T/diagnóstico , Linfoma Cutâneo de Células T/terapia , Técnicas de Diagnóstico Molecular/tendências , Prognóstico , Neoplasias Cutâneas/diagnóstico , Neoplasias Cutâneas/terapia , Terapêutica/tendências , Organização Mundial da SaúdeRESUMO
Merkel cell carcinoma has been a focus of active scientific investigation in recent years and new information on the topic has emerged. Although uncommon, this primary cutaneous neuroendocrine carcinoma, usually involving the head/neck of elderly individuals, has a poor prognosis. Within the past two decades, an increase in the incidence of the tumor and the discovery of its link to the Merkel cell polyomavirus have focused medical attention on the lesion. The resulting studies have improved our understanding of the biology of the neoplasm and contributed to clinical care. Specifically, two pathogenic subsets of the tumor have come to light, the majority due to Merkel cell polyomavirus and the minority caused by ultraviolet radiation-induced genetic damage. This dichotomy carries prognostic implications favoring the former subset. In addition, having capitalized on the known susceptibility of the tumor to immune influences, investigators have recently discovered its responsiveness to immune checkpoint inhibition. This revelation has constituted a therapeutic milestone at the clinical level. Herein we provide an overview of the topic, outline updates in the field and place an emphasis on dermatopathologic aspects of Merkel cell carcinoma.
Assuntos
Carcinoma de Célula de Merkel/diagnóstico , Carcinoma de Célula de Merkel/genética , Carcinoma Neuroendócrino/patologia , Neoplasias Cutâneas/patologia , Raios Ultravioleta/efeitos adversos , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Célula de Merkel/epidemiologia , Carcinoma de Célula de Merkel/virologia , Diagnóstico Diferencial , Feminino , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Humanos , Inibidores de Checkpoint Imunológico/uso terapêutico , Incidência , Masculino , Proteínas de Membrana/metabolismo , Poliomavírus das Células de Merkel/isolamento & purificação , Infecções por Polyomavirus/complicações , PrognósticoRESUMO
The best-known cutaneous manifestations of septicemia in the skin are the so-called "septic vasculitis" and "septic vasculopathy," which represent two sides of the same pathogenetic process. The spectrum of cutaneous presentations of septicemia is, however, more complex, extending beyond septic vasculitis/vasculopathy. We describe the exceptional histopathological findings of skin lesions associated with Stenotrophomonas maltophilia septicemia, featuring a lymphohistiocytic infiltrate characterized by predominance of foamy macrophages containing granular basophilic material negative for PAS, Gram, Fite, and Grocott. Albeit an uncommon occurrence, S. maltophilia septicemia should be included in the broad differential diagnosis of cutaneous lesions occurring in immunocompromised individuals with worsening general conditions. Awareness of these histopathological findings may facilitate the identification of this insidious infectious agent as a source of nosocomial septicemia.
Assuntos
Infecções por Bactérias Gram-Negativas/patologia , Macrófagos/patologia , Sepse/patologia , Dermatopatias/patologia , Stenotrophomonas maltophilia , Adulto , Evolução Fatal , Feminino , Infecções por Bactérias Gram-Negativas/imunologia , Humanos , Hospedeiro Imunocomprometido , Pessoa de Meia-Idade , Sepse/microbiologia , Dermatopatias/imunologia , Dermatopatias/microbiologiaRESUMO
ABSTRACT: Intravascular proliferations of the skin are clinically heterogeneous and may present with a wide range of clinical features, including violaceous papules, nodules, plaques, or other unspecific cutaneous lesions. Histopathologically, these conditions are characterized by proliferation of different cell types within the lumina of dermal vessels and endothelial cell hyperplasia. Immunohistochemistry is the best tool to identify the nature of the intravascular proliferating cells and the type of involved vessel. In this review, we analyzed the clinicopathologic and immunohistochemical characteristics of intravascular large cell lymphoma, T-cell and natural killer-cell intravascular large cell lymphoma, intralymphatic variant of CD30+ cutaneous lymphoproliferative disorders, benign atypical intralymphatic CD30+ T-cell proliferation, reactive angioendotheliomatosis, intralymphatic histiocytosis, papillary intralymphatic angioendothelioma or Dabska tumor, glomeruloid hemangioma, papillary hemangioma, intravascular papillary endothelial hyperplasia or Masson phenomenon, and the intralymphatic involvement of Merkel cell carcinoma, cutaneous metastases, and cutaneous angiosarcoma.
Assuntos
Vasos Sanguíneos/patologia , Dermatopatias Vasculares/patologia , Neoplasias Cutâneas/patologia , Pele/irrigação sanguínea , Animais , Carcinoma de Célula de Merkel/patologia , Proliferação de Células , Células Endoteliais/patologia , Hemangioendotelioma/patologia , Hemangioma/patologia , Histiocitose/patologia , Humanos , Hiperplasia , Linfoma Extranodal de Células T-NK/patologia , Linfoma Difuso de Grandes Células B/patologiaRESUMO
Identification of subtle disease-specific histologic changes may be of significant help in early diagnosis of acantholytic skin diseases. Hailey-Hailey disease (HHD) is an autosomal dominant genodermatosis characterized by vesiculoerosive lesions favoring the intertriginous areas. Histologically, HHD is characterized by full-thickness acantholysis of the spinous layer in association with dyskeratosis of individual keratinocytes; a pemphigus vulgaris-like suprabasal pattern of acantholysis may be observed in the earliest stages of disease. HHD is characterized by highly variable expressivity regarding the age at onset and severity of the disease. Patients may present with late-onset and/or only mild disease. We report the recurrent presence of incidental foci of variably extensive, subclinical acantholysis in multiple bioptic specimens taken from a patient with known HHD for dermatologic conditions other than HHD. Such histologic finding has gone underappreciated in the literature, despite being a likely frequent occurrence in skin biopsies from HHD patients; recognition of this finding might represent a valuable diagnostic clue in selected cases of HHD.
Assuntos
Acantólise/patologia , Pênfigo Familiar Benigno/diagnóstico , Pênfigo Familiar Benigno/patologia , Acantólise/diagnóstico , Acantólise/etiologia , Humanos , Achados Incidentais , Pênfigo Familiar Benigno/complicaçõesRESUMO
Specific cutaneous involvement in Hodgkin lymphoma is rare. In cutaneous lesions, the diagnosis is usually based on the recognition of diagnostic Reed-Sternberg cells and its variants. In nodal Hodgkin lymphoma, so-called mummified cells (cells with condensed cytoplasm and pyknotic eosinophilic or basophilic nuclei) are often seen. They are sometimes conspicuous and easy to recognize, thus serving as a clue to the diagnosis. Our objective was to study cases of cutaneous Hodgkin lymphoma to identify the occurrence of mummified cells. We studied 12 patients (4 women and 8 men; age range 23-80 years). In 6 patients, cutaneous and extracutaneous disease was identified almost simultaneously; in 4 patients, lymph node disease preceded cutaneous involvement; and in the remaining 2 patients, the skin lesions were the presenting sign, whereas lymph node involvement occurred later. Histopathological, immunohistochemical, and molecular-genetic studies, including rearrangements for TCR, IgH genes, and PCR for EBV, were performed. Cutaneous biopsy specimens revealed either a multinodular or diffuse infiltrate, included small lymphocytes, eosinophils, plasma cells, and macrophages, but in all cases, diagnostic Reed-Sternberg cells and its variants were identified. Mummified cells were detected in 9 cases, either as occasional scattered mummified cells often requiring a search (6 cases) or being conspicuous, grouped and therefore easily identified (3 cases). Immunohistochemically, in all 7 cases studied, mummified cells were positive for both CD30 and CD15. It is concluded that mummified cells are encountered in a majority of cases of cutaneous Hodgkin lymphoma.
Assuntos
Doença de Hodgkin/patologia , Neoplasias Cutâneas/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto JovemRESUMO
Blastic plasmacytoid dendritic cell neoplasm (BPDCN) is a rare and aggressive hematologic malignancy for which there is still no effective therapy. In order to identify genetic alterations useful for a new treatment design, we used whole-exome sequencing to analyze 14 BPDCN patients and the patient-derived CAL-1 cell line. The functional enrichment analysis of mutational data reported the epigenetic regulatory program to be the most significantly undermined (P<0.0001). In particular, twenty-five epigenetic modifiers were found mutated (e.g. ASXL1, TET2, SUZ12, ARID1A, PHF2, CHD8); ASXL1 was the most frequently affected (28.6% of cases). To evaluate the impact of the identified epigenetic mutations at the gene-expression and Histone H3 lysine 27 trimethylation/acetylation levels, we performed additional RNA and pathology tissue-chromatin immunoprecipitation sequencing experiments. The patients displayed enrichment in gene signatures regulated by methylation and modifiable by decitabine administration, shared common H3K27-acetylated regions, and had a set of cell-cycle genes aberrantly up-regulated and marked by promoter acetylation. Collectively, the integration of sequencing data showed the potential of a therapy based on epigenetic agents. Through the adoption of a preclinical BPDCN mouse model, established by CAL-1 cell line xenografting, we demonstrated the efficacy of the combination of the epigenetic drugs 5'-azacytidine and decitabine in controlling disease progression in vivo.
Assuntos
Azacitidina/farmacologia , Decitabina/farmacologia , Epigênese Genética/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Neoplasias Hematológicas , Transtornos Mieloproliferativos , Proteínas de Neoplasias , Neoplasias Cutâneas , Idoso , Animais , Linhagem Celular Tumoral , Feminino , Neoplasias Hematológicas/tratamento farmacológico , Neoplasias Hematológicas/genética , Neoplasias Hematológicas/metabolismo , Neoplasias Hematológicas/patologia , Humanos , Masculino , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Pessoa de Meia-Idade , Transtornos Mieloproliferativos/tratamento farmacológico , Transtornos Mieloproliferativos/genética , Transtornos Mieloproliferativos/metabolismo , Transtornos Mieloproliferativos/patologia , Proteínas de Neoplasias/biossíntese , Proteínas de Neoplasias/genética , Neoplasias Cutâneas/tratamento farmacológico , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/metabolismo , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
We review the spectrum of cutaneous disorders associated with inflammatory and neoplastic plasmacytic pathology. Because plasma cells are derived from B-lymphocytes our overview includes discussion of certain lymphoplasmacytic proliferations. It is structured along histopathological lines, addressing conditions characterized by (a) cutaneous plasma cell infiltrates, (b) deposits of plasma cell products or their derivatives in the skin and (c) miscellaneous, poorly understood cutaneous complications of plasmacytic disorders. Lesions arising primarily in the skin and those due to cutaneous involvement by multisystem disorders are addressed. The range includes a spectrum of tumefactive and circulatory manifestations. We highlight key clinical and pathological features of the different conditions and outline recent advances in our understanding of these entities. By emphasizing the dermatopathological characteristics of this spectrum of disorders we hope to hone the diagnostic accuracy of practitioners in the field.
Assuntos
Plasmócitos , Dermatopatias , Pele , Humanos , Plasmócitos/imunologia , Plasmócitos/patologia , Pele/imunologia , Pele/patologia , Dermatopatias/diagnóstico , Dermatopatias/imunologia , Dermatopatias/patologiaRESUMO
Perieccrine inflammation may be observed in several different dermatoses, but true permeation of the secretory coil by lymphocytes (lymphocytic syringotropism) is a rather uncommon finding, usually observed in mycosis fungoides (MF-syringotropic MF). Rare cases of syringotropic lichen striatus and lymphocytic autoimmune hidradenitis showing a similar pattern have been described as well. We describe an exceptional case of lichen planus (LP) characterized by marked lymphocytic syringotropism with focal hyperplasia of the eccrine epithelium. Histopathology was characterized by the combination of features of conventional LP, prominent permeation of the secretory portion of the eccrine glands by reactive lymphocytes, and focal involvement of a hair follicle. Syringotropic LP may be regarded as a histologic mimicker of syringotropic MF, thus representing a potential diagnostic pitfall.
Assuntos
Líquen Plano/diagnóstico , Líquen Plano/patologia , Neoplasias Cutâneas/diagnóstico , Neoplasias Cutâneas/patologia , Adulto , Diagnóstico Diferencial , Feminino , Humanos , Micose Fungoide/diagnóstico , Micose Fungoide/patologiaRESUMO
Despite new horizons opened by recent advances in molecular pathology, histological evaluation still remains the diagnostic gold standard regarding cutaneous melanocytic neoplasms. Several histological variants of melanoma have been described, and their knowledge is crucial for accurate diagnosis and classification of cases with unusual clinico-pathological features. Uncommon histological variants of melanoma have been described based on a broad constellation of features, including architectural pattern, stromal alterations, cytological attributes, and other morphological properties. This review is aimed at providing an extensive discussion of unusual but distinctive histopathological variants of melanoma.
Assuntos
Melanoma/patologia , Neoplasias Cutâneas/patologia , Humanos , Melanoma Maligno CutâneoRESUMO
Despite new horizons opened by recent advances in molecular pathology, histological evaluation still remains the diagnostic gold standard regarding cutaneous melanocytic neoplasms. Several histological variants of melanoma have been described, and their knowledge is crucial for accurate diagnosis and classification of cases with unusual clinicopathological features. Uncommon histological variants of melanoma have been described based on a broad constellation of features, including architectural pattern, stromal alterations, cytological attributes, and other morphological properties. This review is aimed at providing an extensive discussion of unusual but distinctive histopathological variants of melanoma.