914 resultados para ODONTOGENIC TUMORS


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Objetivo: Estimar as probabilidades acumuladas de sobrevida dos pacientes diagnosticados com carcinoma espinocelular nos 10 primeiros anos do Centro de Oncologia Bucal da UNESP, Campus de Araçatuba, de 1991 a 2000, observadas até 2005, estabelecendo os possíveis fatores prognósticos significativos para o óbito. Méttodo: A análise de sobrevida foi realizada em uma coorte de 280 pacientes com carcinoma espinocelular, no Centro de Oncologia Bucal da Faculdade de Odontologia de Araçatuba, UNESP, entre 1991 e 2000. Para avaliar a associação entre as variáveis independentes e o óbito, realizou-se o teste Log Rank. A probabilidade do teste com p-valor menor que 0,25 ficou estabelecida para a inclusão das covariáveis no processo de ajustamento do modelo. A sobrevida foi estimada pelo método de produto limite de Kaplan-Meier. Os fatores prognósticos foram estimados pelo modelo de riscos proporcionais de Cox, calculando-se razão da função de risco (HR). A análise de resíduo foi realizada para verificar o ajuste do modelo. Resultados: As taxas de probabilidades acumuladas de sobrevida de 280 pacientes, para os casos em estádio IV, foram, 56,74%, 32,13%, 23,71% e 20,57%, respectivamente, até 1, 2, 3 e 5 anos após o diagnóstico. Pacientes no estádio I apresentaram sobrevida em 5 anos de 81,73%. O estadiamento clínico da doença no diagnóstico foi o único fator prognóstico definido no processo de ajuste de modelo. A estimativa da razão da função de riscos de morrer em pacientes diagnosticados no estádio III (HR=3,3), é praticamente três vezes o risco daqueles em estádio I; da mesma forma, o risco de morrer dos diagnosticados em estádio IV (HR=6,17) é cerca de seis vezes ao daqueles em estádio I. Conclusões: A covariável que permaneceu no modelo final foi estadiamento clínico no momento do diagnóstico, sendo, pois, o único fator prognóstico.

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Introduction: The Keratocystic Odontogenic Tumor (KCOT) is a benign odontogenic tumor with an infiltrative and potentially aggressive behavior with high recurrence rates. The KCOT occurs more often in men than women, with a frequency of 2:1, being more frequent in the mandible with a predilection for the body and branch. Treatment of KCOT remains controversial. Treatment usually includes enucleation, marsupialization, peripheral ostectomy, curettage associated with Carnoy solution and resection. Objective: To report a case of a KCOT located in the mandible. Case report: male patient, 15 years, with a KCOT on the right side of the mandible treated by enucleation and peripheral ostectomy, with four years of preservation, with no signs of recurrence. Final Comments: The treatment by enucleation associated with peripheral ostectomy reduces the relapse rate, preserves anatomical structures and can avoid a second surgical procedure for reconstruction of bone defects generated in surgery en bloc resection.

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The odontogenic keratocyst is called keratocyst odontogenic tumor (TOQ), due to its features compatible with neoplasms, such as its high recurrence rate and mechanism of growth. Although its etiology has unknown, the origin seems to be connected with dental lamina remaining. This entity is generally benign, with slow progression, asymptomatic, and among the odontogenic tumors, its prevalence is high. It affects mainly males, with predilection for the posterior mandible, while in most cases associated with an impacted tooth. Radiographically, this lesion is unilocular. Histological features are stratified epithelial basal cells with hyperchromatic paraqueratinizado. Treatment ranges from conservative to radical interventions. As a result of the controversy as TOQ tumor entity, the present work is a literature review of current findings, emphasizing its intrinsic features to contribute to developments in the study of this new entity.

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Introduction: the granular cell odontogenic tumors are an uncommon neoplasm with benign clinical behavior. The lesion occurs over a wide age range with a typically predilection for the mandibular canine and molar regions. Aim: present a granular cell odontogenic tumor literature review. Conclusions: the tumor don’t present an aggressive biological behavior although recurrences can occur. The lesion is treated by conservative surgery with curettage and enucleation as election procedures.

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Dental lesions represent about 1% of oral cavity tumors being ameloblastoma the most common one. It is a tumor of epithelial origin that mainly affects the jaw, and less commonly the maxilla. Its clinical presentation is that of an asymptomatic slow-growing tumor. Despite being a benign tumor, it has an invasive behavior with a high rate of recurrence if not treated properly. Objective: To describe the cases of ameloblastoma in a reference department. Methods: Retrospective analysis of 40 cases. The variables analyzed were: age, gender, ethnicity, tumor location, type of treatment, complications and recurrence. Results: The most affected gender was male - 21 cases (52.5%); with a predominance of Caucasians - 24 cases (60%). The mean age was 35.45 years; the most common location was in.the jaw - 37 cases (92.5%). Facial asymmetry was the most frequent complaint. Of the 40 cases, 33 were submitted to surgery. Of those submitted to surgery, 24 (72.72%) underwent segmental resection, with recurrence in 4 (12.12%) cases. Conclusion: Ameloblastoma may relapse when treatment is not performed with broad surgical resection of the lesion with wide safety margins.

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Rho GTPases are proteins that regulate cell cycle, shape, polarization, invasion, migration, and apoptosis, which are important characteristics of normal and neoplastic cells. Rho GTPases expression has been reported in normal tooth germ and several pathologies; however, it has not been evaluated in ameloblastomas. The aim of this study was to analyze the expression and distribution of RhoA, RhoB, Rac1, and Cdc42 Rho GTPases in solid and unicystic ameloblastomas. Three-micrometer sections from paraffin- embedded specimens were evaluated by using an avidin- biotin immunohistochemical method with antibodies against the proteins mentioned above. RhoA and RhoB staining was observed in a high number of cells (P < 0.05) and greater intensity in non-polarized ones. Rac1 was not observed, andCdc42 didnot showany statistical differences between the number of non-polarized and basal positive cells (P > 0.05). Upon comparing the studied ameloblastomas, a higher number of positive cells in the unicystic variant was observed than that in the solid one (P < 0,05). The results obtained suggest that theseGTPases could play a role in the ameloblastoma neoplastic epithelial cell phenotype determination (polarized or non-polarized), as well as in variant (solid or unicystic) and subtype (follicular or plexiform) determination. Furthermore, they could participate in solid ameloblastoma invasion mechanisms. J Oral Pathol Med (2012) 41: 400-407

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The Gorlin-Goltz syndrome, also known as nevoid basal cell carcinoma syndrome (NBCCS), is an infrequent multisystemic disease inherited in a dominant autosomal way, which shows a high level of penetrance and variable expressiveness. It is characterized by keratocystic odontogenic tumors (KCOT) in the jaw, multiple basal cell nevi carcinomas and skeletal abnormities. This syndrome may be diagnosed early by a dentist by routine radiographic exams in the first decade of life, since the KCOTs are usually one of the first manifestations of the syndrome. This article paper reports the case of a patient, a 10-year-old boy with NBCCS, emphasizing its clinical and radiographic manifestations. This study highlights the importance of health professionals in the early diagnosis of NBCCS and in a preventive multidisciplinary approach to provide a better prognosis for the patient.

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O tumor odontogênico cístico calcificante normalmente se manifesta como uma massa indolor, de crescimento lento, que acomete tanto a maxila como a mandíbula, tendo predileção pelo segmento anterior (área dos incisivos e caninos). Geralmente, ocorre em adultos jovens, na terceira a quarta década de vida, sem preferência por gênero. Imagens de tomografia computadorizada revelaram características importantes não detectadas na radiografia panorâmica, tais como fenestração, calcificação e estruturas dentiformes. A característica microscópica típica dessa lesão é a presença de células epiteliais aberrantes anucleadas, em quantidades variáveis, denominadas "células fantasmas". Também se pode encontrar dentina displásica e, ocasionalmente, os cistos estão associados a tecido dentário duro, semelhante ao odontoma. O tratamento do tumor odontogênico cístico calcificante incluiu simples enucleação e curetagem. O objetivo deste trabalho foi mostrar duas manifestações diferentes do tumor odontogênico cístico calcificante, em que a tomografia computadorizada, associada às características clínicas, foi ferramenta importante para o diagnóstico, o planejamento cirúrgico e o acompanhamento dos pacientes.

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The term neurofibromatosis (NF) subsumes at least seven different genetic disorders associated by the presence of neurofibromas located in the skin, oral cavity, visceral and skeletal level. As NF1 (Von Recklinghausen disease), one of the most common genetic diseases, can have oral manifestations, dentists have to be aware about pathognomonic features. The thesis’ target is the literature’s review on the NF1 manifestations either systemic or cefalic area and these features’ research in a specimen of 30 patients NF1 affected. NF1 is manifested in the cefalic area locating either in the jaws (isolated neurofibromas, ipoplasia or bone structures absence) or soft tissues (fibromas and neurofibromas located in: cheeck, lips, oral mucosa, tongue, mouth’s floor, gingiva and palate). Frequently, NF1 patients are affected by dental anomalies of position, number and eruption, that determinates the possibility of orthopaedic-orthodontic problems. An increased prevalence of the caries risk and a possible pulpar involvement of neurofibromas is reported. Clinical and radiographical typical signs of the disease and specific indications for the differential diagnosis with other oral pathologies are described (cysts and odontogenic tumors, periapical lesions of endodontic origin and severe parodontitis). The importance of screening programs and periodical follow-ups (biannual dental visits from the age of four years, annual X-ray checks from the age of six) is supported by the high frequency of manifestations at hard and soft tissues level of the cefalic area and by the documented risk of malignant transformation.

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The following review investigates the term and concept of the globulomaxillary cyst as a correct clinico-pathological diagnosis to describe a so-called fissural cyst said to be caused by epithelial entrapment between the nasal and maxillary process. After analyzing the available literature it has to be concluded that neither from an embryologic nor from a clinical or pathohistological standpoint the term globulomaxillary cyst represents a real entity by itself. Therefore, globulomaxillary cysts have to be diagnosed alternatively after a thorough clinical, radiological and histological examination as other odontogenic cysts like dentigerous cysts or odontogenic keratocysts, odontogenic tumors like ameloblastoma, central giant cell tumors, solitary bone cysts, etc.

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We report a locally aggressive collagenous myofibroblastic neoplasm of the mandible in an 18-year-old male. Clinically, the lesion presented with rapid growth and irregular mandibular bone destruction. Grossly, the tumor was 10 cm in greatest dimension, light-tan, firm, and involving the posterior one-thirds of the body and inferior half of the left mandibular ramus. Histologically, the lesion was composed of a loose spindle cell proliferation interspersed with periodic dense bands of collagen. The spindle cells reacted positively to smooth muscle actin, calponin, and focally to desmin and were negative for S-100, pan-cytokeratin, CD99, CD34 and caldesmon, supporting myofibroblastic derivation. At our 4 year follow-up, the patient remained free of local recurrence and surgery related complications. The clinicopathologic findings and the differential diagnosis of this lesion is presented and discussed.

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The development and progression of odontogenic tumors have been associated with an imbalance in the activity of growth factors, adhesion molecules, extracellular matrix proteins and their degradation enzymes, angiogenic factors and osteolytic. Some studies have shown that interaction relationships inductive epithelial / mesenchymal determinants of Odontogenesis are mimicked by these tumors. The objective of this research was to investigate the immunolocalization of growth factors (BMP-4 and FGF-8) and Sindecan-1 structural protein in a series of odontogenic tumors presenting different biological behaviors, to contribute to a better understanding of the role of these proteins in tumor development. The sample consisted of 21 of the solid ameloblastoma, odontogenic keratocysts 19 and 14 odontogenic adenomatoid tumors. Increased Sindecan-1 immunostaining was seen in the epithelium of the lesions when compared with mesenchyme. In ameloblastoma and odontogenic keratocysts, this expression was higher than in AOT. Epithelial expression of BMP4 showed quantitatively similar in the three studied lesions; however, when anlisada mesenchymal immunoreactivity, was detected significant higher expression when compared to the ameloblastoma keratocysts. In ameloblastoma, mesenchymal expression was predominantly (p = 0.008), while in keratocyst higher expression in the epithelium was observed (p = 0.046). In all injuries, strong or moderate correlation was observed in the BMP-4 immunoreactivity in the epithelium and mesenchyme. FGF-8, no injury was observed difference between the immunoreactivity in the epithelium or mesenchyme, however in ameloblastoma positive correlation was found (Spearman correlation, rho = 0.857, p <0.001). The results of this study suggest that the three evaluated biomarkers actively involved in the pathogenesis of lesions, especially the expression of ameloblastomas indicating a strong interaction between parenchymal and stromal cells which may contribute to its marked aggressiveness.

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INTRODUCTION AND OBJECTIVE: The study of biological behavior of odontogenic lesions is essential to the establishment of appropriate therapeutic approach and prognosis. The production of extracellular matrix metalloproteinases (MMPs), angiogenesis and cell proliferation contribute to tumor growth. This paper aims to review the literature on odontogenic tumors (OT) selected according to the new World Health Organization classification (WHO- 2005) by evaluating the expression of MMPs, angiogenic and cell proliferation. Furthermore, it aims to verify the relation between these markers and the biological behavior of these lesions. RESULTS: it was found that MMPs -1, -2, -7, -9 and -26 had a higher expression in both epithelial component and stroma, and 13 particularly in the stroma. Increased angiogenesis was observed in more aggressive OT. CD105 expression was higher in keratocystic odontogenic tumour (KOT) and CD34 in solid ameloblastomas (SA). It was observed a higher expression of Ki-67 and p53 in SA and KOT and a low cell proliferation rate in the adenomatoid odontogenic tumour (AOT). CONCLUSION: These results show that MMPs are involved in invasion and recurrence of some odontogenic lesions and are associated with the biological behavior of these tumors. Angiogenesis is critical to provide support to cell proliferation and these concomitant events are correlated with different levels of biological behavior in OT when compared to odontogenic cysts, hence the use of angiogenic inhibitors may be a potential therapeutic approach in these lesions.

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INTRODUCTION AND OBJECTIVE: The study of biological behavior of odontogenic lesions is essential to the establishment of appropriate therapeutic approach and prognosis. The production of extracellular matrix metalloproteinases (MMPs), angiogenesis and cell proliferation contribute to tumor growth. This paper aims to review the literature on odontogenic tumors (OT) selected according to the new World Health Organization classification (WHO- 2005) by evaluating the expression of MMPs, angiogenic and cell proliferation. Furthermore, it aims to verify the relation between these markers and the biological behavior of these lesions. RESULTS: it was found that MMPs -1, -2, -7, -9 and -26 had a higher expression in both epithelial component and stroma, and 13 particularly in the stroma. Increased angiogenesis was observed in more aggressive OT. CD105 expression was higher in keratocystic odontogenic tumour (KOT) and CD34 in solid ameloblastomas (SA). It was observed a higher expression of Ki-67 and p53 in SA and KOT and a low cell proliferation rate in the adenomatoid odontogenic tumour (AOT). CONCLUSION: These results show that MMPs are involved in invasion and recurrence of some odontogenic lesions and are associated with the biological behavior of these tumors. Angiogenesis is critical to provide support to cell proliferation and these concomitant events are correlated with different levels of biological behavior in OT when compared to odontogenic cysts, hence the use of angiogenic inhibitors may be a potential therapeutic approach in these lesions.

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Keratocystic odontogenic tumor (KCOT) is a benign intraosseous neoplasm of odontogenic origin with high recurrence rate. To date, various conservative or aggressive management strategies have been suggested as a method of treatment. Decompression is a conservative method that has been used in the treatment of large odontogenic cysts. The present paper reports a case of KCOT located in the mandible and discusses the importance of its management using conservative methods. The authors present a case of a 38-year-old patient with a KCOT located in the right mandibular angle and ascending ramus, which was treated by decompression followed by enucleation and curettage. The lesion did not recur during a follow-up period of 3 years after surgery. Preserving important structures of the bone and soft tissue decompression is a method with low morbidity. In addition, according to the literature, decompression has a success rate at least as high as the one of most aggressive treatments.