Imunoexpressão das proteínas EGFR e VEGF em lipomas de cavidade oral / Immunoexpression of EGFR and VEGF proteins in oral cavity lipomas

Lipomas são as neoplasias mesênquimais benignas mais comuns. Apresentam predileção pelo tronco, ombros, pescoço e axila, sendo raro nas mãos, parte inferior das pernas e pés. A região de cabeça e pescoço é responsável por 20% dos casos. A cavidade oral é responsável por 1-4% de todos os tumores, afeta de maneira semelhante o sexo feminino e masculino, acometendo ampla faixa etária. A etiopatogênia desse tumor ainda permanece desconhecida, dessa forma, essa pesquisa teve como objetivo detectar, quantificar e comparar a expressão imunoistoquímica do EGFR, VEGF e contagem microvascular (MVC) dos lipomas orais, relacionando-os com as características clínicas e morfológicas dos casos estudados. A amostra foi composta por 54 lipomas orais (33 clássicos e 21 não clássicos) e 23 casos de tecido adiposo normal. A análise da expressão imunoistoquímica de EGFR e VEGF foi fundamentada na marcação da membrana citoplasmática e/ou núcleo. O índice angiogênico foi avaliado por meio da contagem microvascular (MVC). A contagem de células foi realizada utilizando software IMAGE J®. Os dados obtidos foram analisados no software Statistical Package for Social Science. O nível se significância de 5% foi adotado para os testes estatísticos (p ≤ 0,05). A Análise da imunoexpressão das proteínas revelou para o EGFR diferença estatisticamente significativa (p=0,041) entre o lipoma clássico e o tecido adiposo normal. Com relação a contagem de microvasos, o CMV dos lipomas não clássico apresentou diferença estatisticamente significativa (p=0,018) em relação ao tecido adiposo normal. Nos lipomas não clássicos, apenas a imunoexpressão de VEGF esteve diretamente proporcional a CMV encontrado na neoplasia, com correlação do tipo moderada, positiva e significativa (p=0,010). Ademais, nos lipomas clássicos foi percebido que os adipócitos imunomarcados para EGFR estiveram diretamente proporcionais a imunoexpressão de VEGF, isso deve-se a correlação do tipo moderada, positiva e estatisticamente significativa (p = 0,005). Com base nos resultados, pode-se concluir que apesar do EGFR, VEGFR e CMV participarem do desenvolvimento neoplásico, é possível sugerir que nos lipomas, essas proteínas e o CMV não estejam primariamente envolvidos no crescimento tumoral (AU).

Lipomas are the most common benign mesenchymal neoplasms. They have a predilection for the trunk, shoulders, neck and armpit, being rare in the hands, lower legs and feet. The head and neck region accounts for 20% of cases. The oral cavity is responsible for 1-4% of all tumors, affecting females and males in a similar way, affecting a wide age range. The etiopathogenesis of this tumor remains unknown, therefore, this research aimed to detect, quantify and compare the immunohistochemical expression of EGFR, VEGF and microvascular count (MVC) of oral lipomas, relating them to the clinical and morphological characteristics of the cases studied . The sample consisted of 54 oral lipomas (33 classic and 21 non-classical) and 23 cases of normal adipose tissue. The analysis of the immunohistochemical expression of EGFR and VEGF was based on cytoplasmic membrane and/or nucleus labeling. The angiogenic index was assessed using microvascular count (MVC). Cell counting was performed using IMAGE J® software. The data obtained were analyzed using the Statistical Package for Social Science software. A significance level of 5% was adopted for statistical tests (p ≤ 0.05). Analysis of protein immunoexpression revealed a statistically significant difference (p=0.041) for EGFR between classic lipoma and normal adipose tissue. Regarding microvessel count, the CMV of non-classic lipomas showed a statistically significant difference (p=0.018) in relation to normal adipose tissue. In non-classical lipomas, only VEGF immunoexpression was directly proportional to the CMV found in the neoplasm, with a moderate, positive and significant correlation (p=0.010). Furthermore, in classical lipomas it was noticed that adipocytes immunolabeled for EGFR were directly proportional to VEGF immunoexpression, this is due to the moderate, positive and statistically significant correlation (p = 0.005). Based on the results, it can be concluded that although EGFR, VEGFR and CMV participate in neoplastic development, it is possible to suggest that in lipomas, these proteins and CMV are not primarily involved in tumor growth (AU).

Lipoma oral: Revisión de literatura y reporte de caso / Oral lipoma: Review of literature and case report

Resumen Los lipomas son considerados los tumores de origen mesenquimatoso más comunes del tejido blando; de ellos el 13% del total se ubican en cabeza y cuello, pero es difícil encontrarlos en la región oral y maxilofacial. La localización más común de lipomas dentro de la región oral y maxilofacial ha sido reportada en la mucosa bucal, lengua y piso de boca. Los lipomas son neoplasias que se presentan típicamente como una masa suave, de superficie lisa, nodular, amarillenta y asintomática. Histopatológicamente, el lipoma clásico asemeja un tejido normal adiposo y tiene múltiples variantes. Este artículo presenta el reporte de caso de un lipoma oral extenso en un paciente femenino de 46 años de edad en la mucosa yugal, tratado quirúrgicamente con adecuada evolución. Asimismo se realiza la revisión de literatura con sus variantes histopatológicas.

Abstract Lipomas are considered the most frequent mesenchymal tumors of soft tissue, 13% are located in head and neck but it´s difficult to find them in the oral and maxillofacial region. The most common location of lipomas within the oral and maxillofacial region has been reported in the buccal mucosa, tongue and floor of the mouth. Lipomas are neoplasias that typically present as a soft, smooth-surfaced, nodular, yellowish, and asymptomatic mass. Histopathologically, the classical lipoma resembles normal adipose tissue and it has multiple variants. This article presents a case report of a relatively large oral classical lipoma in a 46 year-old woman on mandibular buccal vestibule, along with a review of the literature and its histopatho-logical variants.

Lipoma of the oral mucosa: a case report

Lipoma is a common tumor of soft tissue. Its location on the oral mucosa is rare, representing 1% to 5% of benign oral tumors although it is the most common mesenchymal tumor of the trunk and proximal portions of extremities. Lipoma of the oral cavity may occur in any region. The buccal mucosa, tongue, and floor of the mouth are among the common locations. The clinical presentation is typically as an asymptomatic yellowish mass. The overlying epithelium is intact, and superficial blood vessels are usually evident over the tumor. Other benign connective tissue lesions such as granular cell tumor, neurofibroma, traumatic fibroma and salivary gland lesions (mucocele and mixed tumor) might be included in differential diagnosis. We present a case of oral lipoma in an unusual location in the left palatal region opposite to premolars which is rare in the literature.

Angiofibrolipoma of the oral cavity.

We describe an unusual and rare case of a lipoma variant known as angiofibrolipoma. A literature search revealed only a few cases of angiofibrolipoma which were located in different anatomical sites; no case of angiofibrolipoma in the oral cavity has been previously reported. We present and discuss the histopatholological-immunohistological findings and features. Angiofibrolipoma histologically consists of mature adipocytes, blood vessels, and bundles of collagenous connective tissue with low to moderate cellularity. It is not encapsulated, but is histologically distinct from surrounding tissue. Positive immunohistological staining with CD-34 presented a large number of blood vessels of different sizes located between collagen fibers and adipocytes. The treatment of choice for a patient with angiofibrolipoma is surgical excision, which is expected to be curative.