Oral Burkitt's Lymphoma - Case Report

SummaryBurkitt's lymphoma is a poorly differentiated rare and aggressive type of non-Hodgkin's lymphoma. This article reports the case of a male child aged seven years, who was examined at the Odontopediatric Clinic of the UFRN Dentistry Department. The patient presented a tumor in the premolar region of the mandible; teeth were mobile in this region. Radiology revealed a diffuse radioluscent area which was diagnosed histopathologically as Burkitt's lymphoma. The patient was treated with polychemotherapy; complete remission of the disease was attained

Tenascina e fibronectina em adenoma pleomórfico de glândula salivar

OBJECTIVES: To analyze the expression and distribution pattern of extracellular matrix components in pleomorphic adenomas of the major and minor salivary glands and to compare the morphological findings of these tumors with the immunohistochemical expression, considering the different types of stroma predominating in each case. METHODS AND RESULTS: The expression of tenascin (TN) and fibronectin (FN) was analyzed in 23 cases of pleomorphic adenomas, 11 major and 12 minor salivary gland tumors, by the streptavidin-biotin method using anti-tenascin and anti-fibronectin antibodies. In addition, the immunohistochemical results were correlated with the morphological findings of the lesions. All cases analyzed were immunoreactive for the antibodies used. Fibronectin showed strong labeling in fibrous and chondroid stroma, while labeling was weak in hyaline and myxoid stroma. Tenascin expression was more intense in fibrous and chondroid stroma and moderate in hyaline and myxoid stroma. CONCLUSIONS: No difference in the expression of these proteins was observed between major and minor salivary gland tumors.OBJETIVO: Analisar a expressão e o padrão de distribuição de componentes da matriz extracelular em adenomas pleomórficos de glândula salivar maior e menor e comparar os achados morfológicos destes tumores com a expressão imuno-histoquímica considerando os diferentes tipos de estromas presentes em cada caso. MÉTODOS E RESULTADOS: A expressão da tenascina (TN) e fibronectina (FN) foi analisada em 23 casos de adenomas pleomórficos, sendo 11 tumores em glândula salivar maior e 12 em glândula salivar menor, utilizando-se o método da estreptoavidina-biotina para os anticorpos anti-tenascina e anti-fibronectina. Os resultados imuno-histoquimicos foram correlacionados com os achados morfológicos das lesões. Todos os casos foram imunorreativos para a fibronectina mostrando forte expressão nos estromas fibrosos e condróides, embora fraca marcação tenha sido evidenciada nos estromas hialinos e mixóides. A expressão da tenascina foi mais intensa nos estromas condróides e fibrosos, sendo moderada nos estromas hialino e mixóide. CONCLUSÕES: Não houve diferença na expressão destas proteínas entre os tumores de glândula salivar maior e menor

Clinicopathologic analysis of 7 cases of oral schwannoma and review of the literature?

Schwannomas, also known as neurilemmomas, are uncommon neoplasms apparently derived from Schwann cells. The growth of these tumors causes displacement and compression of the nerve of origin. Schwannomas are usually solitary lesions but can be multiple when associated with neurofibromatosis. Anti-S100 protein is the most widely used antibody for the identification of this neoplasm. Surgical excision is the treatment of choice for schwannomas, with few and controversial reports of recurrence or malignant transformation. The present article reports 7 additional cases of oral schwannoma, and the literature is reviewed regarding clinicopathologic features, immunohistochemical findings, differential diagnosis, and therapeutic management of this benign neural tumor

Botryoid odontogenic cyst: a clinicopathologic study of 10 cases

Botryoid odontogenic cyst is a rare multilocular variant of lateral periodontal cysts. In this study, a series of 10 cases of botryoid odontogenic cysts retrieved from the archives of the Postgraduation Program in Oral Pathology, Federal University of Rio Grande do Norte (Brazil), were reviewed for epidemiologic data, clinical presentation, radiographic and histopathologic characteristics, treatment, and recurrence

Mast cells and matrix metalloproteinase 9 expression in actinic cheilitis and lip squamous cell carcinoma

Objectives The aim of this study was to evaluate mast cell (MC) density and migration and their association with matrix metalloproteinase (MMP) 9 expression in squamous cell carcinoma (SCC) and actinic cheilitis (AC). Study design Tryptase, c-Kit, and MMP-9 expression was evaluated in 20 cases of SCC, 20 cases of AC, and 7 cases of normal lip (control samples) by immunohistochemistry techniques. Results Tryptase+ and c-Kit+ MC densities were significantly higher in SCCs than in ACs and control samples (P < .001). However, no significant difference was found when comparing tryptase+ and c-Kit+ MC densities between ACs and control samples (P values .185 and .516, respectively). MMP-9 was strongly expressed in SCCs and moderately expressed in ACs and control samples. A highly significant association was found between tryptase+ MC density and the expression of MMP-9 (P < .001). Conclusions The increase in MC density associated with the strong expression of MMP-9 may favor SCC progression

Intra-Oral Spitz Naevus: A Case Report

The Spitz nevus, also known as benign juvenile melanoma or a nevus of epitheloid and spindle cells, was first described by Sophie Spitz in 1948 and is most common in children and adolescents. They can present in three different ways: solitary nodular, multiple grouped, and multiple disseminated. The great majority of lesions are solitary, nodular, and are present in children and adolescents (57%–70%), with a slight preference for the female gender. The regions where they are most frequently found are the lower extremities, the head and neck, and the trunk. A Spitz nevus is usually pink, brown, or black in color. After an initial period of growth, the majority of Spitz nevi tend to stabilize their growth, reaching, in 95% of patients, a final size smaller than 6 mm

Immunohistochemical expression of matrilysins (MMP-7 and MMP-26) in ameloblastomas and adenomatoid odontogenic tumors

OBJECTIVE: The aim was to evaluate the expression of matrix metalloproteinases (MMPs) 7 and 26 in ameloblastomas and adenomatoid odontogenic tumors (AOTs). STUDY DESIGN: Twenty intraosseous solid ameloblastomas and 10 intraosseous AOTs were evaluated regarding immunohistochemical expression of MMP-7 and -26 in the epithelium and stroma. RESULTS: There was no statistically significant difference in MMP-7 and -26 expression between the epithelium of ameloblastomas (P = .50) and AOTs (P = .90). Stromal staining for MMP-7 was evident in all cases. For MMP-26, stromal staining was observed in 65% of ameloblastomas and 50% of AOTs, and this difference was not statistically significant (P = .69). CONCLUSION: The marked expression of these matrilysins suggests their role in the process of tissue remodeling and growth in the studied tumors, but it does not relate to the their distinct patterns of aggressiveness

MicroRNAs - biogênese, funções e seu papel potencial na carcinogênese oral

MicroRNAs (miRNAs) são pequenos RNAs não-codantes, conservados ao longo da evolução, capazes de regular a expressão gênica através da degradação ou repressão da tradução de moléculas-alvo de RNA mensageiro. A expressão dos miRNAs se apresenta desregulada em diversos processos patológicos, incluindo o câncer. Dependendo do contexto e do tipo celular em que são expressos, um mesmo miRNA pode exibir atividade oncogênica ou supressora tumoral. Dessa forma, a função dos miRNAs pode, em última instância, depender do microambiente específico de determinado tipo celular, o qual pode prover diferentes repertórios de genes-alvo. Entretanto, as alterações na expressão dos miRNAs podem constituir um achado secundário ao próprio fenótipo tumoral e, dessa forma, ainda não está completamente claro se a expressão alterada dos miRNAs constitui causa ou consequência da transformação maligna. O presente estudo realiza uma revisão da literatura sobre miRNAs, enfocando aspectos relacionados à biogênese, mecanismos de ação e o papel potencial desses pequenos RNAs na carcinogênese oral

Expression of extracellular matrix proteins in ameloblastomas and adenomatoid odontogenic tumors

This study evaluated the expression of fibronectin, tenascin and type I collagen in ameloblastomas and adenomatoid odontogenic tumors (AOTs) aiming to contribute with the comprehension of the differences in the biological behavior of these tumors. Immunohistochemical technique was performed in 20 cases of ameloblastoma (16 solid and 4 desmoplastic) and in 10 cases of AOT. All tumors presented moderate fibronectin expression in the stroma. Solid ameloblastomas showed intense expression of fibronectin at the epithelial-mesenchymal interface, whereas desmoplastic ameloblastomas revealed no immunoexpression of fibronectin at this site. Ameloblastomas presented stronger immunoreactivity to tenascin than AOTs, especially at the epithelial-mesenchymal interface. AOTs and desmoplastic ameloblastomas showed intense labeling for type I collagen. The patterns of expression of the proteins studied agree with the locally more invasive behavior of ameloblastomas in comparison to AOTs. Our results might suggest a less invasive behavior of desmoplastic ameloblastoma in comparison to solid ameloblastoma

Immunohistochemical study of components of the basement membrane in odontogenic cysts

Com o objetivo de observar o padrão de distribuição de proteínas da membrana basal de cistos odontogênicos, foi realizado um estudo imuno-histoquímico em dez espécimes de cisto radicular, dez cistos dentígeros e dez ceratocistos odontogênicos, por meio do uso de anticorpos antilaminina e anticolágeno IV. Os resultados mostraram uma marcação linear fraca e descontínua nos ceratocistos, tanto da laminina, quanto do colágeno IV, enquanto nos cistos radiculares, esta marcação foi mais intensa e contínua. Nos cistos dentígeros, foi observado um padrão intermediário, tendendo mais ao observado nos ceratocistos. Nossos resultados sugerem que, através da fraca expressão das proteínas de membrana basal observada nos ceratocistos odontogênicos, possíveis modificações nas relações interativas entre o epitélio e o tecido conjuntivo adjacente devem acontecer, o que poderia contribuir, em parte, para o padrão de crescimento mais agressivo exibido por este tipo de cisto.The pattern of distribution and expression of laminin and type IV collagen was studied in ten radicular cysts, ten dentigerous cysts and ten odontogenic keratocysts, by means of the streptavidin-biotin method. The purpose of this study was to investigate changes in the distribution of components of the basement membrane in an attempt to contribute to the understanding of the differences, as to evolution and clinical behavior, between these cysts. The results revealed a weak and discontinuous linear staining, in odontogenic keratocysts, for both laminin and type IV collagen, while, in radicular cysts, staining was more intense and continuous. In dentigerous cysts, an intermediary pattern was observed, which was more similar to that observed in keratocysts. Our results suggest that, in view of the weak expression of proteins of the basement membrane observed in odontogenic keratocysts, modifications must take place in the interaction between the epithelium and the adjacent connective tissue, which could, in part, contribute to the pattern of more rapid growth exhibited by these cysts