Altered ß-catenin expression in oral mucosal dysplasia: a comparative study.

OBJECTIVE: The current study aimed to investigate the ß-catenin expression in oral leukoplakia (OL) with different degrees of epithelial dysplasia and normal oral mucosa. MATERIAL AND METHODS: Formalin-fixed, paraffin-embedded tissue samples of 39 OL (mild dysplasia n=19, moderate dysplasia n=13, and severe dysplasia n=7), and 10 normal oral mucosa (control group) were submitted to immunohistochemical reactions to anti-ß-catenin primary antibody. A qualitative ß-catenin analysis was performed based on the percentage of positive cells. The cellular location and the epithelial layer were also considered. The Chi-square test and the Fisher's exact test were used to verify possible differences in the ß-catenin expression among the OL groups. A p-value of <0.05 was considered statistically significant. RESULTS: Membranous expression of ß-catenin in parabasal and basal layers was gradually lost in the higher degrees of epithelial dysplasia. In normal oral mucosa, ß-catenin was detected only in the cytoplasmic membrane. However, a significant increase in cytoplasmic ß-catenin could be observed between mild and moderate dysplasia (Fisher Exact test - p<0.001) and between mild and severe dysplasia (p<0.001). CONCLUSIONS: The ß-catenin cytoplasmic expression observed in this study may represent the initial stage of modifications in the E-cadherin-catenin complex, along with morphological cellular changes.

Oral focal mucinosis of the hard palate and gingiva

Oral focal mucinosis (OFM) is an uncommon, asymptomatic, submucosal, slow-growing nodule representing a counterpart of the cutaneous focal mucinosis (CFM). OFM has a female predilection with the highest prevalence in the fifth decade of life. About 68% of OFMs occur in the gingiva and 14% in the palate. We present the case of a 41-year-old woman presenting a progressively growing mass on the palate, since the last 8 months. The diagnostic workup led to the diagnosis of an unusual OFM with the clinical presentation involving the gingiva and hard palate. This case report discusses the clinical and histopathological differential diagnosis.

Cellular proliferation markers in peripheral and central fibromas: a comparative study.

OBJECTIVE: To perform a comparative study of the cellular proliferation in the peripheral and central fibromas. MATERIAL AND METHODS: Immunohistochemistry for PCNA and the AgNOR technique were performed in 9 cases of peripheral odontogenic fibroma (POF), in 4 cases of odontogenic fibroma (OdF), in 8 cases of peripheral ossifying fibroma (PEOF) and 7 cases of ossifying fibroma (OsF). The Kruskal-Wallis and Mann-Whitney tests were used for the statistical analyses. RESULTS: Mesenchymal component of the central lesions presented a higher mean number of AgNOR per nucleus and PCNA index than did the peripheral lesions (P≤0.05). The mean number of AgNOR per nucleus in the epithelial component proved to be higher in the OdF than in the POF (P≤0.05). The mesenchymal and epithelial components presented similar mean numbers of AgNOR per nucleus and PCNA index in the OdF, as well as a similar mean number of AgNOR per nucleus in the POF. CONCLUSIONS: The mesenchymal component may well play a role in the differences between the biological behaviour of the central lesions as compared to the peripheral lesions. Moreover, considering that the epithelial and mesenchymal components in odontogenic fibromas presented a similar proliferation index, more research is warranted to understand the true role of the epithelial components, which are believed to be inactive in nature, as well as in the development and biological behaviour of these lesions.

Extra-tongue oral granular cell tumor: Histological and immunohistochemical aspect

BACKGROUND: Granular cell tumor (GCT) is an uncommon benign tumor founded in any part of the body but mainly in the tongue. Extra-tongue oral granular cell tumor (ETOGCT) is rare with few cases reported. Here we describe seven cases of oral GCT located in sites other than the tongue and discuss histopathological and immunohistochemical differences between differential diagnoses. MATERIAL AND METHODS: We retrieved all cases diagnosed with oral granular cell tumor, from the Oral Pathology Service at the School of Dentistry/ University of Săo Paulo, and excluded the ones sited in the tongue. Immunohistochemical staining anti-S100 was also performed. RESULTS: The presented cases of Extra-tongue Oral Granular Cell Tumor (ETOGT) are composed by granular cells with intimately association with the adjacent tissue. Atypia and mitoses were not seen, and in most cases, the typical pseudoepitheliomatous hyperplasia was not observed. CONCLUSIONS: The importance of an adequate attention is to avoid misdiagnoses, since ETOGT is rare and the tricking histopathological findings could induce to it. All the cases can be differentiated from the tumors that has a granular cell proliferation through a morphological analysis and when needed, immunohistochemistry stain

Altered ß-catenin expression in oral mucosal dysplasia: a comparative study

Objective The current study aimed to investigate the β-catenin expression in oral leukoplakia (OL) with different degrees of epithelial dysplasia and normal oral mucosa.Material and Methods Formalin-fixed, paraffin-embedded tissue samples of 39 OL (mild dysplasia n=19, moderate dysplasia n=13, and severe dysplasia n=7), and 10 normal oral mucosa (control group) were submitted to immunohistochemical reactions to anti-β-catenin primary antibody. A qualitative β-catenin analysis was performed based on the percentage of positive cells. The cellular location and the epithelial layer were also considered. The Chi-square test and the Fisher’s exact test were used to verify possible differences in the β-catenin expression among the OL groups. A p-value of <0.05 was considered statistically significant.Results Membranous expression of β-catenin in parabasal and basal layers was gradually lost in the higher degrees of epithelial dysplasia. In normal oral mucosa, β-catenin was detected only in the cytoplasmic membrane. However, a significant increase in cytoplasmic β-catenin could be observed between mild and moderate dysplasia (Fisher Exact test - p<0.001) and between mild and severe dysplasia (p<0.001).Conclusions The β-catenin cytoplasmic expression observed in this study may represent the initial stage of modifications in the E-cadherin-catenin complex, along with morphological cellular changes.

Peripheral Ameloblastoma with Dystrophic Calcification: An Unusual Feature in Non-Calcifying Odontogenic Tumors

Peripheral ameloblastoma is a rare extraosseous counterpart of central ameloblastoma that occurs in soft tissues and may cause bone crest resorption. This study reports a peripheral ameloblastoma on the buccal gingiva of a 56-year-old man, which presented extensive squamous metaplasia areas, keratinization and dystrophic calcifications in the neoplastic islands. It is emphasized the need of a detailed imaging study and a long follow-up period to exclude bone involvement whenever peripheral ameloblastoma diagnosis is considered.

Ameloblastoma periférico é a contraparte rara extraóssea do ameloblastoma central, que ocorre em tecidos moles e pode causar reabsorção da crista óssea. Este estudo reporta um ameloblastoma periférico localizado na gengiva vestibular de um homem de 56 anos de idade, que apresentava extensas áreas de metaplasia escamosa, queratinização e calcificação distrófica dentro das ilhas neoplásicas. É enfatizada a necessidade de um estudo de imagem detalhado e acompanhamento prolongado para excluir envolvimento ósseo sempre que o diagnóstico de ameloblastoma periférico for considerado.

Clinical and Histological Features of Multifocal Canalicular Adenomas of the Upper Lip

Canalicular adenoma (CA) is an uncommon benign salivary gland tumor that mostly occurs in the upper lip. Despite its benign nature, some patients may present multiple nodules and also microscopic growth that can be multifocal with foci of tumor within the adjacent gland. Microscopically, CA can be mistaken for a polymorphous low-grade adenocarcinoma (PLGA) or basal cell adenoma (BCA), and immunohistochemistry can be helpful in differentiating them. Two cases of canalicular adenoma showing tumor foci within the adjacent gland are described. Both cases occurred in the upper lip of white females aged 72 and 79 years. In addition to the histological multifocal aspect, one of the patients presented bi-lateral nodules. Histological examination of both lesions revealed interconnecting and branching canal-like structures composed by uniform columnar and sometimes cuboidal cells, partially encapsulated. Immunohistochemical analysis showed intense expression of cytokeratins (CK) 7, a weak reaction to CK14 and a negative reaction to vimentin. Upon the diagnosis of CA the lesions were excised. In conclusion, it is important to properly diagnose CA and differentiate its multifocal aspect from a malignant behavior.

O adenoma canalicular (AC) é uma rara neoplasia benigna de glândula salivar que ocorre com maior frequência em lábio superior. Apesar de sua natureza benigna, alguns pacientes podem apresentar múltiplos nódulos, além de apresentar microscopicamente um crescimento multifocal com focos de neoplasia na glândula adjacente. Microscopicamente, AC pode ser confundido com adenocarcinoma polimorfo de baixo grau ou adenoma de células basais, sendo a imunohistoquímica útil na diferenciação entre eles. Dois casos de AC com focos de neoplasia dentro da glândula são descritos. Ambos os casos ocorreram em lábio superior de dois indivíduos do sexo feminino com 72 e 79 anos de idade. Além do aspecto histológico multifocal, um dos pacientes apresentou nódulos bilaterais. A análise histológica dos dois casos revelou estruturas canaliculares interligadas, compostas por células colunares uniformes e cuboidais, parcialmente encapsuladas. A análise imunohistoquímica mostrou intensa marcação de citoqueratina (CK) 7, uma fraca expressão para CK14, e reação negativa para vmentina. Após o diagnóstico as lesões foram excisionadas. Conclusão: É importante o correto diagnóstico do AC e a diferenciação do aspecto multifocal de um comportamento maligno.

Cellular proliferation markers in peripheral and central fibromas: a comparative study

ABSTRACT Objective: To perform a comparative study of the cellular proliferation in the peripheral and central fibromas. Material and Methods: Immunohistochemistry for PCNA and the AgNOR technique were performed in 9 cases of peripheral odontogenic fibroma (POF), in 4 cases of odontogenic fibroma (OdF), in 8 cases of peripheral ossifying fibroma (PEOF) and 7 cases of ossifying fibroma (OsF). The Kruskal-Wallis and Mann-Whitney tests were used for the statistical analyses. Results: Mesenchymal component of the central lesions presented a higher mean number of AgNOR per nucleus and PCNA index than did the peripheral lesions (P≤0.05). The mean number of AgNOR per nucleus in the epithelial component proved to be higher in the OdF than in the POF (P≤0.05). The mesenchymal and epithelial components presented similar mean numbers of AgNOR per nucleus and PCNA index in the OdF, as well as a similar mean number of AgNOR per nucleus in the POF. Conclusions: The mesenchymal component may well play a role in the differences between the biological behaviour of the central lesions as compared to the peripheral lesions. Moreover, considering that the epithelial and mesenchymal components in odontogenic fibromas presented a similar proliferation index, more research is warranted to understand the true role of the epithelial components, which are believed to be inactive in nature, as well as in the development and biological behaviour of these lesions. .

Study of the inflammatory process induced by injection of carrageenan or formalin in the rat temporomandibular joint.

The aim of this study was to evaluate the effects of the injection of two phlogistic agents, carrageenan and formalin, in the rat TMJ, and the inflammatory process induced by these substances. In this study, a total of 45 adult rats were distributed in two experimental groups and a control group. The animals were sacrificed after three hours, 24 hours, three days, seven days, and 15 days after a single injection of each substance. Histological data initially demonstrated an inflammatory process represented by acute infiltration, which later became mixed, and finally chronic in both experimental groups. Hyperplasia of the synovial membrane was observed after three days, being intense at seven days, and present after 15 days only in the formalin group. Local saline injection in the control group caused no inflammatory reaction. It was concluded that a single local injection of carrageenan or formalin was enough to induce inflammatory reaction in the TMJ and periarticular soft tissues, and that the resulting processes were similar, but more persistent in the formalin group.

Study of the inflammatory process induced by injection of carrageenan or formalin in the rat temporomandibular joint

O objetivo deste trabalho foi avaliar os efeitos da injecão de dois agentes flogísticos, ou seja, carragenina ou formalina, na ATM do rato, e a evolucão do quadro inflamatório provocado por essas substâncias. Foram utilizados 45 ratos, divididos em dois grupos experimentais e um grupo controle. Os animais foram sacrificados em lotes de três de cada grupo após três horas, 24 horas, três dias, sete dias e 15 dias da injecão. Histologicamente a reacão inflamatória em ambos os grupos experimentais iniciou-se com infiltrado inflamatório agudo, tornando-se misto e depois crônico. Sinais de hiperplasia da membrana sinovial foram observados aos três dias, intensos aos sete dias, estando presentes aos 15 dias somente no grupo da formalina. A injecão de solucão salina (grupo controle) não provocou reacão inflamatória. No presente trabalho foi concluído que uma injecão local única na região da ATM de carragenina ou de formalina foi suficiente para induzir reacão inflamatória na articulacão e nos tecidos moles periarticulares. As reacões inflamatórias resultantes da injecão desses agentes flogísticos foram semelhantes, mas o grupo da formalina mostrou infiltrado inflamatório mais persistente.

Fibronectin as an adjuvant in the diagnosis of oral inflammatorymyofibroblastic tumor

Inflammatory myofibroblastic tumor is a distinctive lesion composed of myofibroblastic spindle shaped cells accompaniedby inflammatory infiltrate that may arise in various organs. It is believed to be a noneoplastic inflammatorycondition, although this is still controversial. The recognition of inflammatory myofibroblastic tumor asan entity is important especially to avoid unnecessary surgery. A few cases have been reported in the oral cavity.This report primarily presents a case of inflammatory myofibroblastic tumor that arose in the floor of mouth ofa 23-year-old woman. The proliferating spindle cells were immunoreactive for vimentin, smooth muscle actin,and muscle specific actin and negative for desmin, AE1/AE3, S-100, CD68, MyoD1 and caldesmon. In an attemptto assess the potential neoplastic nature of this lesion, immunohistochemical expression of ALK protein wasperformed, although no immunoreactivity was detected. Also, the presence of well differentiated myofibroblastsidentified by fibronectin is discussed, as well as the importance in establishing an immunoprofile to better consolidatethe diagnosis. We conclude that the study of fibronectin in case series may aid the diagnosis as well as theprediction of the tumor course (AU)

No disponible

Análise epidemiológica de pacientes acometidos com paracoccidioidomicose em regiäo endêmica do estado de Minas Gerais / Epidemiologic study of patients with paracoccidioidomycosis in an endemic region of Minas Gerais

A paracoccidioidomicose é uma micose autóctone da América Latina, sendo as maiores causuísticas registradas no Brasil, Argentina, Colômbia e Venezuela. Com a finalidade de identificar dados relevantes sobre a história clínica e patológica, sistêmica e oral dos pacientes com a micose, foram analisados 92 prontuários de casos de paracoccidioidomicose do Arquivo Nosológico do Hospital-Escola da Faculdade de Medicina do Triângulo Mineiro da cidade de Uberaba - MG, que ocorreram entre os anos de 1982 a 1997. A análise dos dados revelou que 100 pacientes foram internados com a micose nos últimos 15 anos, com média anual de 6,6 casos, com maior prevalência para indivíduos do sexo masculino entre 31 e 50 anos de idade, afetando principalmente aqueles envolvidos com atividades agrícolas. Foi observada a ausência de um protocolo específico para a coleta de informaçöes anamnésicas, principalmente as de interesse odontológico, dos pacientes internados em decorrência da micose. Também, näo se observou nenhum tipo de intervençäo odontológica durante o tratamento, bem como no prognóstico e proservaçäo das lesöes orais ocorridas

Expression of different keratins in salivary gland tumours / Expressão de diferentes queratinas em tumores de glândulas salivares

Twenty-four salivary gland tumours (six pleomorphic adenomas, two myoepitheliomas, five basal cell adenomas, six adenoid cystic carcinomas and five polymorphous low grade adenocarcinomas) were investigated by an immunocytochemical technique using monoclonal antibodies against cytokeratins (CKs) 7, 8, 10, 13, 14, 18 and 19. The luminal cells of ductal structures of the tumours reacted with all the CKs studied except for CK 13 and CK 10 and sometimes CK 14, showing an immunoprofile comparable to that of the intercalated segment of a normal salivary gland. The outer cells of the ducts rarely stained with CK 14, confirming that full differentiation of the myoepithelial cells is seldom achieved in tumours. Considerations were made regarding the intriguing expression of CK 14, the heterogeneous expression of CKs in the modified myoepithelial cells and the immunoprofile of the polymorphous low-grade adenocarcinoma

Estudo morfológico e imuno-histoquímico do adenoma pleomórfico de glândula salivar menor / Morphological and immunohistochemical study of minor salivary gland pleomorphic adenoma

Cinqüenta e um casos de adenomas pleomórficos de glândula salivar menor pertencentes aos arquivos do Serviço de Patologia Cirúrgica da Faculdade de Odontologia da Universidade de Säo Paulo foram estudados à microscopia de luz e por imuno-histoquímica. O exame à microscopia de luz mostrou que nos tumores estudados o tipo celular predominante era o poligonal, seguido do tipo hialino. As células estavam dispostas em cordöes, ilhotas ou lençóis, ou ainda estavam dispostas em estroma dos tipos fibroso, mixocondróide ou hialino, sendo este último o mais freqüente. A reaçäo imuno-histoquímica revelou que entre os anticorpos utilizados (antiqueratina, vimentina e proteína S-100), a vimentina mostrou-se o melhor marcador da célula tumoral, estando presente em todos os seus fenotipos

Fibroma ossificante periférico e fibroma ossificante: estudo utilizando a técnica do AgNOR / Paripheral ossifyng fibroma and ossifyng fibroma: study with the AgNOR technique

Avaliaçäo da proliferaçäo celular através da análise quantitativa e morfométrica das regiöes organizadoras nucleolares (NORs) foi realizada em 10 casos de fibromas ossificantes periféricos e em 10 casos de fibromas ossificantes, com a finalidade de coletar informaçöes sobre essas duas entidades. Para a identificaçäo das NORs, realizamos a técnica da prata coloidal, conhecida como técnica do AgNOR. Com a análise dos parâmetros das NORs, verificamos, para ambas as lesöes que apresentam comportamento benigno; entretanto, essa própria análise demonstrou uma atividade proliferativa maior do fibroma ossificante em relaçäo ao fibroma ossificante periférico

Estudo imuno-histoquímico da desmoplasia em neoplasias de glândula salivar / Immunohistochemical study of desmoplasia in salivary gland neoplasms

Desmoplasia é a deposição proeminente de colágeno de permeio às células neoplásicas, tendo-se o miofibroblasto como a célula responsável por esse processo. Sua presença tem sido associada a um prognóstico mais favorável em algumas neoplasias e, diante disso, propusemo-nos a estudar sua presença em neoplasias de glândula salivar. A fim de verificar a presença do miofibroblasto no estroma tumoral dessas neoplasias, utilizamos a técnica imuno-histoquímica através do método EnVision-peroxidase com o anticorpo anti-actina-músculo-liso (AML) nos casos selecionados de: adenoma pleomórfico - AP (6), carcinoma mucoepidermóide - CME (21) carcinoma adenóide cístico - CAC (7), carcinoma epitelial-mioepitelial - CEM (2), adenocarcinoma polimorfo de baixo grau de malignidade - APBGM (11) e carcinoma de células acinares - CCA (2). Apenas os casos de CME, APBGM e CCA exibiram positividade para o anticorpo, confirmando a presença do miofibroblasto, em graus variáveis de acordo com cada variante tumoral. Apenas nos casos de CMEs pôde ser verificada a relação entre a presença da desmoplasia e a menor agressividade do tumor. Nos demais casos (AP, CAC, CEM e CCA), essa relação não existiu, o que nos levou à conclusão de que, nos tumores de glândula salivar, o comportamento e as reações diferem entre as entidades, ficando claro que, nesses tumores, deve-se individualizar o estudo do estroma

Leiomyosarcoma of the buccal mucosa: a case report / Leiomyosarcoma da mucosa bucal: relato de caso

Leiomyosarcomas account for 6 per cent to 7 per cent of soft tissues sarcomas. Their main site of occurrence is in the uterus, gastrointestinal tract, and retroperitoneum; they are extremely rare in the oral and maxillofacial region. In 1995, Izumi et al reviewed 60 examples of oral leiomyosarcoma, of which only six (10 per cent) cases occurred in the buccal mucosa. The definitive histologic diagnosis of oral leiomyosarcoma is difficult because of the similarity with other sarcomas that are composed of fascicles of moderately differentiated spindle cells. Immunohistochemical analysis for cytoskeletal proteins such as actin, vimentin, myosin, and desmin has been widely used for the diagnosis of leiomyosarcoma. The purpose of this report is to describe a case of leiomyosarcoma of the buccal mucosa and its immunohistochemical features that were useful in arriving at the final diagnosis

Proliferative activity in peripheral ossifying fibroma and ossifying fibroma / Atividade proliferativa no fibroma ossificante periférico e fibroma ossificante central

A proliferative activity study analysing morphometric and quantitative aspects of nucleolar organizer regions (NORs) and proliferating cell nuclear antigen (PCNA) expression was conducted in 10 cases of peripheral ossifying fibroma (POF) and 10 cases of ossifying fibroma (OF). For NOR identification, the silver staining technique (AgNOR technique) was used. PCNA expression was determined by immunohistochemical staining using the PC10 antibody. The AgNOR analysis for the two lesions showed a profile characteristic of benign lesions. Of showed higher AgNOR number and PCNA expression than POF. Our results suggest increased proliferative activity in OF compared with POF

Adenocarcinoma polimorfo de baixo grau de malignidade do tipo papilífero: estudo morfológico e imuno-histoquímico / Polymorphous low-grade adenocarcninoma of the papillary type: a morphological and immunohistochemical study

No presente trabalho foram estudados dois casos de adenocarcinoma polimorfo de baixo grau de malignidade do tipo papilífero, de glândulas salivares menores, através de microscopia de luz e imuno-histoquímica. Um dos casos exibiu predominância do padräo papilífero, enquanto o outro apresentou os seguintes padröes histológicos: papilífero, sólido, pseudocístico e tubular. Utilizando o método da peroxidase-antiperoxidase (PAP), o filamento intermediário vimentina, queratina e a proteína S100 foram observados nas células tumorais. A análise imuno-histoquímica revelou dois tipos de células neoplásicas: mioepitelial e luminal

Immunohistochemical analysis of 89 benign salivary gland tumors

Oitenta e nove tumores benignos de glândula salivar foram examinados imunohistoquimicamente utilizando-se anticorpos disponíveis no mercado para queratina, proteína S-100 e vimentina. Nossos resultados mostraram que a queratina é um bom marcador de células luminal, a vimentina é muito importante para a identificaçäo da célula mioepitelial tumoral enquanto a marcaçäo pela proteína S-100 é variável. Nossos achados confirmam a opiniäo de que a vimentina é um dos primeiros marcadores da diferenciaçäo neoplásica da célula mucoepitelial