RESUMO
Congenital divided melanocytic nevi of the upper and lower eyelid are rare pigmented changes of the eyelids. These processes are also known as "kissing nevi," "panda nevi," and "split ocular nevi," and were first described by Fuchs in 1919. About 120 cases have been described in the literature so far. Congenital melanocytic nevi are either present at birth (small nevi are already found in about 1% of neonates) or manifest predominantly during the first decade of life. These rare melanocytic changes of the eyelids should be controlled regularly, as malignant transformation can occur. The actual incidence of malignant transformation is highly variable in the literature, ranging from 2 to 40% depending on the duration of follow-up, with an average of 14% for the whole lifetime. Moreover, nevi of the eyelids may be considered cosmetically disturbing and cause functional problems. Therapeutic removal (dermabrasion, cryotherapy, laser therapy, and surgical excision with ophthalmoplastic reconstruction) is rarely medically indicated due to the low risk of malignant transformation. Removal can be performed in cases of secondary amblyopia in ptosis, compression of the lacrimal point, epiphora, or cosmetic desire. Treatment becomes necessary not only in case of suspicious manifestation or impairment of eyelid function, but it also helps to avoid possible bullying at school among children and is recommended at age 4 to 6 (before school age).
Assuntos
Terapia a Laser , Nevo de Células Epitelioides e Fusiformes , Nevo Pigmentado , Neoplasias Cutâneas , Humanos , Criança , Recém-Nascido , Pré-Escolar , Nevo Pigmentado/cirurgia , Nevo de Células Epitelioides e Fusiformes/cirurgia , Pálpebras/cirurgia , Transformação Celular Neoplásica/patologia , Neoplasias Cutâneas/cirurgiaRESUMO
BACKGROUND: Atypical Spitz tumours (ASTs) are regarded as an intermediate category distinguished from prototypical Spitz naevus by presenting one or more atypical features and often by an uncertain malignant potential. Clinical and dermoscopic features may play a relevant role in the diagnostic approach. AIM: To evaluate the clinical and dermoscopic features of ASTs, and their evolution over time. METHODS: This was a descriptive, multicentre study of the clinical and dermoscopic characteristics of ASTs. Data on clinical and dermoscopic characteristics, histopathology, local extension, therapy and follow-up, lymph node staging, complete lymph node dissection, and outcome were collected from the databases of four Italian Dermatology Units for the period 2004-2021. RESULTS: The study population consisted of 99 patients (62 female, 37 male) with a histologically confirmed diagnosis of AST, including age at presentation ranged from 2 to 70 years (mean 28.1 years, median 24 years). Of the 99 patients, 29 (29.3%) underwent sentinel lymph node biopsy, which showed evidence of micrometastases in three cases (10.3%); all three patients underwent complete lymph node dissection with no evidence of further metastasis. Considering the whole study population, the clinical outcome was excellent, as all of the patients have no evidence of recurrence or distant metastasis. The follow-up period ranged from 6 to 216 months (mean 81.6 months, median 78 months). In addition, we collected data on the clinical and dermoscopic features of 26 lesions. The most frequent dermoscopic pattern observed was the multicomponent pattern (34.6%), followed by homogeneous (26.9%) and nonspecific (23.2%). In 66.7% of amelanotic ASTs, we observed glomerular (coiled) vessels uniformly distributed within the entire lesion, without asymmetry. CONCLUSION: The results of our study with a long follow-up show no recurrence or distant metastases, confirming the good clinical outcome, even in the case of sentinel lymph node positivity. From a diagnostic point of view, our series identified a typical dermoscopic picture for amelanotic ASTs, with a glomerular vascular pattern throughout the lesion in the absence of other dermoscopic parameters, making the correct diagnosis possible.
Assuntos
Nevo de Células Epitelioides e Fusiformes , Neoplasias Cutâneas , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Feminino , Seguimentos , Humanos , Excisão de Linfonodo , Masculino , Pessoa de Meia-Idade , Nevo de Células Epitelioides e Fusiformes/diagnóstico , Nevo de Células Epitelioides e Fusiformes/epidemiologia , Nevo de Células Epitelioides e Fusiformes/cirurgia , Biópsia de Linfonodo Sentinela , Neoplasias Cutâneas/diagnóstico por imagem , Neoplasias Cutâneas/epidemiologia , Adulto JovemRESUMO
Spitzoid melanocytic lesions describe a spectrum of pediatric melanocytic proliferations ranging from benign Spitz nevi to malignant spitzoid melanomas typically arising within the first two decades of life. Atypical spitzoid neoplasm (ASN) is a poorly defined category within this spectrum that poses a unique diagnostic challenge due to histologic findings with insufficient atypical characteristics to make the diagnosis of melanoma. This report presents an exceptionally rare case of an ulcerative atypical spitzoid neoplasm mimicking an infantile hemangioma in a two-month-old girl treated with pulse dyed laser (PDL) and surgical excision. Our patient ultimately underwent five excisions over a 2-year period, with successful maintenance of function and dexterity of the affected fingers.
Assuntos
Melanoma , Nevo de Células Epitelioides e Fusiformes , Neoplasias Cutâneas , Criança , Diagnóstico Diferencial , Feminino , Humanos , Lactente , Melanócitos , Melanoma/diagnóstico , Nevo de Células Epitelioides e Fusiformes/diagnóstico , Nevo de Células Epitelioides e Fusiformes/cirurgia , Neoplasias Cutâneas/diagnóstico , Neoplasias Cutâneas/cirurgiaRESUMO
Abstract Melanoma in childhood is rare and its diagnosis is more difficult than in adults, as it often presents histologic features overlapping with the Spitz nevus. The authors report the case of a 17-year old boy who was first diagnosed with Spitz nevus, however, the final diagnosis made after the excision of the tumor arising in the scar was changed to melanoma. The case in this present study emphasizes the importance of the differential diagnosis of skin tumors in young patients.
Assuntos
Humanos , Masculino , Criança , Adolescente , Adulto , Neoplasias Cutâneas/cirurgia , Neoplasias Cutâneas/diagnóstico , Nevo de Células Epitelioides e Fusiformes/cirurgia , Melanoma/cirurgia , Melanoma/diagnóstico , Cicatriz , Diagnóstico Diferencial , Recidiva Local de Neoplasia/cirurgiaRESUMO
Melanoma in childhood is rare and its diagnosis is more difficult than in adults, as it often presents histologic features overlapping with the Spitz nevus. The authors report the case of a 17-year old boy who was first diagnosed with Spitz nevus, however, the final diagnosis made after the excision of the tumor arising in the scar was changed to melanoma. The case in this present study emphasizes the importance of the differential diagnosis of skin tumors in young patients.
Assuntos
Melanoma , Nevo de Células Epitelioides e Fusiformes , Neoplasias Cutâneas , Adolescente , Adulto , Criança , Cicatriz , Diagnóstico Diferencial , Humanos , Masculino , Melanoma/diagnóstico , Melanoma/cirurgia , Recidiva Local de Neoplasia/cirurgia , Nevo de Células Epitelioides e Fusiformes/cirurgia , Neoplasias Cutâneas/diagnóstico , Neoplasias Cutâneas/cirurgiaRESUMO
BACKGROUND: Spitz nevi are benign melanocytic neoplasms that typically present as rapidly growing solitary lesions on the head, neck, or lower extremities. Very rare reports have been described in African Americans. METHODS: A single-institution 29-year retrospective review of African American patients diagnosed with Spitz nevi was thoroughly analyzed in order to characterize these rare clinical and histopathologic presentations. RESULTS: Eleven African Americans with spitzoid lesions were identified. Seven (64%) cases were in pediatric patients and nine (82%) were in females. Most lesions were hyperpigmented (73%) and elevated (82%). Six (55%) were compound Spitz nevi, three (27%) were dermal Spitz nevi, and two (18%) were junctional Spitz nevi. Two lesions had more than one atypical feature. Histopathologically, common features were symmetry, sharp circumscription, pagetoid spread (55%) with most being centrally, predominance of epithelioid cells (64%), Kamino bodies (45%), slight pigmentation (46%), maturation of dermal component with depth, and lack of subcutaneous fat involvement or ulceration. Excision was performed on all patients and there were no recurrences although follow-up was limited. CONCLUSION: Awareness of the possibility and various presentations of Spitz nevi in African Americans will help prevent misdiagnosis.
Assuntos
Negro ou Afro-Americano/etnologia , Células Epitelioides/patologia , Nevo de Células Epitelioides e Fusiformes/diagnóstico , Transtornos da Pigmentação/patologia , Neoplasias Cutâneas/patologia , Adolescente , Adulto , Negro ou Afro-Americano/estatística & dados numéricos , Conscientização , Criança , Pré-Escolar , Diagnóstico Diferencial , Erros de Diagnóstico/prevenção & controle , Feminino , Cabeça/patologia , Humanos , Lactente , Extremidade Inferior/patologia , Masculino , Margens de Excisão , Pessoa de Meia-Idade , Pescoço/patologia , Nevo de Células Epitelioides e Fusiformes/cirurgia , Nevo de Células Epitelioides e Fusiformes/ultraestrutura , Estudos Retrospectivos , Adulto JovemRESUMO
With the advent of better molecular characterization of Spitz melanocytic neoplasms, there has been increasing effort to better understand and describe the relationships between specific driver fusion and/or mutations with the clinical and histomorphological characteristics of the lesions. Structural rearrangements in mitogen activated protein kinase genes have recently been noted to be important in Spitz neoplasms. Only very few reports, however, have described in detail melanocytic tumors with in frame deletions in MAP2K1. Cases in the literature with this aberration have been described as having a diagnosis of Spitz, deep penetrating nevi, or pigmented epithelioid melanocytoma. In this study, we describe a cohort of 6 cases with MAP2K1 activating in frame deletions. The morphologic spectrum of the cases was broad. Common features of these cases include Spitzoid cytomorphology (5/6) cases, prominent melanin pigmentation (4/6) cases, and deep penetrating nevi-like plexiform architecture (3/6) cases. The diagnoses at the time of clinical care of these cases included nevus of Reed (1/6), desmoplastic Spitz tumor (1/6), BAPoma (1/6), deep penetrating melanocytic nevus (2/6), and melanoma (1/6). Clinical follow-up was available in 3 of the 6 cases. None of the patients had a tumor recurrence. This builds on the growing literature to help expand the spectrum of changes associated with Spitzoid melanocytic neoplasms.
Assuntos
Mutação da Fase de Leitura , MAP Quinase Quinase 1/genética , Nevo de Células Epitelioides e Fusiformes/genética , Neoplasias Cutâneas/genética , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Análise Mutacional de DNA , Bases de Dados Factuais , Feminino , Predisposição Genética para Doença , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Masculino , Pessoa de Meia-Idade , Nevo de Células Epitelioides e Fusiformes/enzimologia , Nevo de Células Epitelioides e Fusiformes/patologia , Nevo de Células Epitelioides e Fusiformes/cirurgia , Fenótipo , Estudos Retrospectivos , Neoplasias Cutâneas/enzimologia , Neoplasias Cutâneas/patologia , Neoplasias Cutâneas/cirurgia , Resultado do Tratamento , Adulto JovemRESUMO
Angiomatoid Spitz nevus (ASN) is a rare histological variant of Spitz nevus (SN) that is characterized by prominent blood vessel proliferation around the intradermal melanocytes of SN. In contrast, SN may have pagetoid components, which are characterized by epidermal proliferation of single melanocytes. However, cases of ASN with predominant pagetoid melanocytic proliferation in the epidermis have not been reported. Here, we report a case of ASN with surrounding pagetoid melanocytic proliferation without formation of tumor nests in the epidermis in the plantar region. A 12-year-old girl presented with a bright red nodule surrounded by a brown macule on the sole of her right foot. Histologically, the nodule showed tumor nests in the dermis, composed of spindle or epithelioid melanocytes containing abundant cytoplasm and large nuclei. Around the nests, numerous blood vessels were seen. In the overlying epidermis of the nodule, numerous eosinophilic Kamino bodies were found along the dermal-epidermal interface. In the macule, proliferation of oval melanocytes was present as single-cell units in the epidermis. Theses melanocytes had abundant cytoplasm with large nuclei, which were larger than those of the surrounding keratinocytes. From these findings, a diagnosis of ASN with surrounding pagetoid melanocytic proliferation was made. Vascular endothelial growth factor and fibroblast growth factor 2 were strongly expressed in the melanocytes as well as in the endothelial cells in our case. Therefore, angiogenic factors produced by the melanocytes of SN might have played important roles in the surrounding angiogenesis of this case.
Assuntos
Melanócitos/patologia , Neovascularização Patológica/patologia , Nevo de Células Epitelioides e Fusiformes/diagnóstico , Neoplasias Cutâneas/diagnóstico , Pele/patologia , Proliferação de Células , Criança , Dermoscopia , Células Endoteliais/patologia , Endotélio Vascular/citologia , Endotélio Vascular/patologia , Feminino , Fator 2 de Crescimento de Fibroblastos/análise , Fator 2 de Crescimento de Fibroblastos/metabolismo , Pé , Humanos , Imuno-Histoquímica , Nevo de Células Epitelioides e Fusiformes/patologia , Nevo de Células Epitelioides e Fusiformes/cirurgia , Pele/irrigação sanguínea , Pele/citologia , Pele/diagnóstico por imagem , Neoplasias Cutâneas/patologia , Neoplasias Cutâneas/cirurgia , Fator A de Crescimento do Endotélio Vascular/análise , Fator A de Crescimento do Endotélio Vascular/metabolismoAssuntos
Perfilação da Expressão Gênica , Melanoma/diagnóstico , Nevo de Células Epitelioides e Fusiformes/diagnóstico , Neoplasias Cutâneas/diagnóstico , Pele/patologia , Fatores Etários , Idoso , Diagnóstico Diferencial , Estudos de Viabilidade , Feminino , Humanos , Masculino , Melanoma/patologia , Melanoma/cirurgia , Pessoa de Meia-Idade , Nevo de Células Epitelioides e Fusiformes/genética , Nevo de Células Epitelioides e Fusiformes/patologia , Nevo de Células Epitelioides e Fusiformes/cirurgia , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/patologia , Neoplasias Cutâneas/cirurgiaRESUMO
BACKGROUND: Spitz nevi (or tumors) are noncancerous growths that are found particularly in the pediatric population. Their histologic features overlap with melanoma, but they have a favorable prognosis, even when showing atypical features. OBJECTIVES: The aim of this research is to examine whether Spitz nevi can be sufficiently removed by adequate shave excisions without a subsequent excision. METHODS: Melan-A stained shave removal specimens (SRS) were obtained for 58 consecutively diagnosed Spitz nevi, along with slides of their postshave excision specimens. The SRS were reviewed for negative (clear) margins, defined as no neoplastic melanocytes detected within <0.2 mm of the deep and lateral margins of the specimen. Postshave excision specimens were reviewed for residual or recurrent lesions. RESULTS: The 15 shave excision specimens with negative margins had no corresponding residual lesions on postshave specimens. There were no recurrences in any of the cases in an average of 17 months of follow-up. CONCLUSIONS: Observation may be a logical approach for the management of Spitz nevi when shave removal achieves clear margins and the lesion lacks atypical features.
Assuntos
Biópsia/métodos , Nevo de Células Epitelioides e Fusiformes/patologia , Nevo de Células Epitelioides e Fusiformes/cirurgia , Adolescente , Adulto , Idoso , Criança , Diagnóstico Diferencial , Feminino , Humanos , Masculino , Margens de Excisão , Melanoma/patologia , Melanoma/cirurgia , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Neoplasias Cutâneas/patologia , Neoplasias Cutâneas/cirurgia , Adulto JovemAssuntos
Neoplasias Labiais/patologia , Nevo de Células Epitelioides e Fusiformes/patologia , Neoplasias Cutâneas/patologia , Pré-Escolar , Diagnóstico Diferencial , Feminino , Humanos , Neoplasias Labiais/classificação , Neoplasias Labiais/cirurgia , Nevo de Células Epitelioides e Fusiformes/classificação , Nevo de Células Epitelioides e Fusiformes/cirurgia , Neoplasias Cutâneas/classificação , Neoplasias Cutâneas/cirurgiaRESUMO
BACKGROUND: Dermatopathologists routinely use Ki67 immunostaining to assess atypical melanocytic lesions with a dermal component to determine whether an ambiguous tumor is melanoma. However, there is no universal standard of use for Ki67 in melanocytic neoplasms. We sought to observe the real-world use of Ki67 in the diagnosis of melanocytic lesions and establish a best practice recommendation. METHODS: We searched dermatopathology reports from 2 academic practices for melanocytic lesions in which Ki67 staining was used for diagnosis. The proliferation rate was compared between cases diagnosed as benign (not requiring re-excision), moderate to severely dysplastic or atypical Spitz nevi (requiring re-excision), and malignant melanoma. The use of other melanocytic markers and consensus review was also recorded and compared between institutions. RESULTS: Pathology reports for 106 cases were reviewed. A high Ki67 proliferation rate (n = 18) favored a diagnosis of melanoma or nevi requiring re-excision (15/18, 83.3%) versus a benign nevus (3/18, 16.67%). A high Ki67 rate was 71.4%-90.9% sensitive and 40%-56% specific for the diagnosis of nevus requiring re-excision or melanoma. Institutional practices differed in regard to reporting of Ki67 staining, the use of multiple markers in the workup of atypical melanocytic lesions (HMB45, Melan-A, Ki67 being most common), and consensus review. CONCLUSIONS: A negative or low Ki67 proliferation rate correlates well with rendering of a benign diagnosis. However, a low proliferation rate does not preclude the diagnosis of melanoma. Ki67 staining is most commonly used as an ancillary test to support a diagnosis after other factors have been considered, such as histopathologic morphology and results of additional concurrently used stains.
Assuntos
Antígeno Ki-67/metabolismo , Melanoma/diagnóstico , Nevo de Células Epitelioides e Fusiformes/diagnóstico , Neoplasias Cutâneas/diagnóstico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Feminino , Humanos , Imuno-Histoquímica/estatística & dados numéricos , Masculino , Melanoma/metabolismo , Melanoma/cirurgia , Pessoa de Meia-Idade , Índice Mitótico , Nevo de Células Epitelioides e Fusiformes/metabolismo , Nevo de Células Epitelioides e Fusiformes/cirurgia , Reoperação , Sensibilidade e Especificidade , Neoplasias Cutâneas/metabolismo , Neoplasias Cutâneas/cirurgia , Adulto JovemRESUMO
BACKGROUND: Melanoma is an infrequent neoplasm in children and adolescents. The number of consultancies for melanocytic nevi control in the pediatric population is increased by the major anxiety of parents and pediatricians. METHODS: A retrospective chart review was performed in order to evaluate the incidence rate of melanoma, Spitz nevi, congenital and acquired melanocytic nevi in patients aged 14 years or less and referred to our institution from April 2010 to September 2015. RESULTS: A total of 32,755 dermatologic pediatric consultancies were performed in the considered 66 months period, including 4260 patients referred for mole control (13%). During the same period, a total of 5193 excisions of melanocytic lesions were performed (adults and pediatric patients), 259 of which were performed in 250 patients aged 14 years or less (4.98%). Only 1 in situ melanoma of the nail matrix was detected in a 12-year-old female patient (0.38% of surgical excisions). The number needed to excise (NNE) in our pediatric population, calculated by comparing the total number of excised lesions and the number of melanomas found, was 259. CONCLUSIONS: Our data leads to 3 major observations: 1) the rarity of melanoma in patients with 14 years of age or less is confirmed; 2) the number of excisions performed in this pediatric population is extremely high; 3) neither the cases of melanoma and atypical Spitz neoplasm (ASN) nor the majority of Spitz nevi were referred to us for a generic mole control. Mole controls in the pediatric population should be properly addressed, incrementing the attention on specific suspicious cutaneous lesions.
Assuntos
Melanoma/epidemiologia , Nevo de Células Epitelioides e Fusiformes/epidemiologia , Nevo Pigmentado/epidemiologia , Neoplasias Cutâneas/epidemiologia , Adolescente , Criança , Feminino , Humanos , Masculino , Melanoma/cirurgia , Nevo de Células Epitelioides e Fusiformes/cirurgia , Nevo Pigmentado/cirurgia , Encaminhamento e Consulta/estatística & dados numéricos , Estudos Retrospectivos , Neoplasias Cutâneas/cirurgiaAssuntos
Procedimentos Cirúrgicos Dermatológicos/métodos , Gerenciamento Clínico , Nevo de Células Epitelioides e Fusiformes/diagnóstico , Neoplasias Cutâneas/diagnóstico , Pele/patologia , Criança , Diagnóstico Diferencial , Feminino , Seguimentos , Humanos , Masculino , Nevo de Células Epitelioides e Fusiformes/cirurgia , Estudos Retrospectivos , Neoplasias Cutâneas/cirurgiaAssuntos
Pavilhão Auricular/patologia , Neoplasias da Orelha/congênito , Nevo de Células Epitelioides e Fusiformes/congênito , Neoplasias Cutâneas/congênito , Neoplasias Cutâneas/patologia , Biópsia , Pré-Escolar , Dermoscopia , Pavilhão Auricular/cirurgia , Neoplasias da Orelha/patologia , Neoplasias da Orelha/cirurgia , Humanos , Masculino , Nevo de Células Epitelioides e Fusiformes/patologia , Nevo de Células Epitelioides e Fusiformes/cirurgia , Neoplasias Cutâneas/cirurgiaRESUMO
BACKGROUND: ALK receptor tyrosine kinase gene (ALK) rearrangements have been described in spitzoid lesions with a plexiform growth pattern. OBJECTIVE: To investigate the prevalence of ALK alterations in a large series of spitzoid lesions. METHODS: ALK immunohistochemical and fluorescence in situ hybridization analyses of 78 spitzoid plexiform lesions including 41 Spitz nevi, 29 atypical Spitz tumors (ASTs), and 8 spitzoid melanomas. RESULTS: ALK immunohistochemical staining was observed in 14.6% of Spitz nevi (6 of 41) and 13.8% of ASTs (4 of 29); the spitzoid melanomas were ALK negative. Fluorescence in situ hybridization confirmed ALK translocation in 9 cases and amplification in 1 case. In 2 of the translocated cases it was possible to determine the fusion partner gene (ie, tropomyosin 3 gene [TPM3] or dynactin 1 gene [DCTN1]). Of the 4 cases of AST examined, 2 carried the B-Raf proto-oncogene, serine/threonine kinase gene (BRAF) V600E mutation. The 10 patients had a mean age of 18.7 years (range, 1-39) and a female predominance (female-to-male ratio, 7:3). Seven lesions arose on the extremities; the 2 lesions occurring in infants were located on the face. The lesions' mean diameter was 6.2 mm (range, 3-13), and their mean Breslow thickness was 1.83 mm (range, 0.6-3.6). The results of sentinel node biopsy were negative in 2 ASTs. LIMITATIONS: BRAF status was tested in only 4 of 10 samples because of the limited amount of material. CONCLUSION: ALK alterations characterize a significant subset of spitzoid lesions.
Assuntos
Quinase do Linfoma Anaplásico/genética , Predisposição Genética para Doença/epidemiologia , Nevo de Células Epitelioides e Fusiformes/genética , Nevo de Células Epitelioides e Fusiformes/patologia , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/patologia , Adolescente , Adulto , Criança , Pré-Escolar , Estudos de Coortes , Feminino , Variação Genética , Humanos , Imuno-Histoquímica , Hibridização in Situ Fluorescente , Masculino , Mutação , Invasividade Neoplásica/patologia , Estadiamento de Neoplasias , Nevo de Células Epitelioides e Fusiformes/cirurgia , Prognóstico , Proto-Oncogene Mas , Reação em Cadeia da Polimerase em Tempo Real/métodos , Estudos Retrospectivos , Biópsia de Linfonodo Sentinela , Neoplasias Cutâneas/cirurgia , Adulto JovemRESUMO
Spitz nevus is a type of melanocytic nevus that can arise as a solitary lesion or as multiple lesions either disseminated or agminated (grouped) in different skin backgrounds (eg, grossly normal, hyperpigmented, or hypopigmented). Agminated Spitz nevi have been rarely reported and are even rarer in a background of hypopigmented skin. We present the case of a 2-month-old girl with multiple, grouped, dome-shaped, red papules arising on a hypopigmented patch with a segmental distribution. Biopsy of 2 lesions showed findings characteristic of Spitz nevus, confirming the diagnosis. We also review 4 other cases of agminated Spitz nevi arising on hypopigmented skin reported in the literature.
Assuntos
Hipopigmentação/patologia , Nevo de Células Epitelioides e Fusiformes/patologia , Neoplasias Cutâneas/patologia , Biópsia , Feminino , Humanos , Hipopigmentação/cirurgia , Lactente , Nevo de Células Epitelioides e Fusiformes/cirurgia , Neoplasias Cutâneas/cirurgiaRESUMO
Spitz nevi on acral sites are rare and poorly documented. The combination of Spitzoid cytomorphology and atypical architectural features of the junctional component may lead to an erroneous diagnosis of melanoma. To study the clinicopthologic and immunohistochemical features, 50 Spitz nevi localized on the distal extremities were retrieved from departmental files. Clinical data and follow-up were obtained and the histologic features were analyzed. P16 and P21 immunohistochemical staining of the dermal component was compared with that of 10 acral lentiginous melanomas and 10 acral nevi. Acral Spitz nevi affected young adults (median: 24.5 y; range: 4 to 61 y) with a female predominence and a predilection for the feet. They were pigmented measuring 1 to 15 mm (median: 4 mm). Follow-up, available for 45 patients (median: 48 mo; range: 4 to 228 mo), revealed no local recurrence, metastasis or mortality. Histologically, acral Spitz nevi were composed of large epithelioid and/or spindled melanocytes. They were well circumscribed with occasional asymmetry. The junctional component was broad with a lentiginous and nested growth and shoulder formation. Marked pagetoid spread and transepidermal elimination of junctional nests were common features. Focal active regression of the dermal component was frequently noted but there was no nuclear pleomorphism or dermal mitotic activity. Acral Spitz nevi were characterized by strong and diffuse P16 and P21 expression, which differs from acral nevi and acral lentiginous melanoma. Acral Spitz nevi are a distinctive subgroup of Spitz nevi with benign behavior. Awareness of the subtle histologic differentiating features and the distinctive P16/P21 expression pattern allows separation from melanoma.