Diagnostic capability of artificial intelligence tools for detecting and classifying odontogenic cysts and tumors: a systematic review and meta-analysis.

OBJECTIVE: To evaluate the diagnostic capability of artificial intelligence (AI) for detecting and classifying odontogenic cysts and tumors, with special emphasis on odontogenic keratocyst (OKC) and ameloblastoma. STUDY DESIGN: Nine electronic databases and the gray literature were examined. Human-based studies using AI algorithms to detect or classify odontogenic cysts and tumors by using panoramic radiographs or CBCT were included. Diagnostic tests were evaluated, and a meta-analysis was performed for classifying OKCs and ameloblastomas. Heterogeneity, risk of bias, and certainty of evidence were evaluated. RESULTS: Twelve studies concluded that AI is a promising tool for the detection and/or classification of lesions, producing high diagnostic test values. Three articles assessed the sensitivity of convolutional neural networks in classifying similar lesions using panoramic radiographs, specifically OKC and ameloblastoma. The accuracy was 0.893 (95% CI 0.832-0.954). AI applied to cone beam computed tomography produced superior accuracy based on only 4 studies. The results revealed heterogeneity in the models used, variations in imaging examinations, and discrepancies in the presentation of metrics. CONCLUSION: AI tools exhibited a relatively high level of accuracy in detecting and classifying OKC and ameloblastoma. Panoramic radiography appears to be an accurate method for AI-based classification of these lesions, albeit with a low level of certainty. The accuracy of CBCT model data appears to be high and promising, although with limited available data.

Nova classificação da OMS para tumores odontogênicos: o que mudou? / Updated WHO classification for odontogenic tumors: what has changed?

Objetivo: apresentar e discutir as mais relevantes modificaçõesna quarta classificação de tumores de cabeçae pescoço da Organização Mundial de Saúde (OMS),no ano de 2017, especialmente para os tumores odontogênicos.Revisão de literatura: o trabalho baseia-seem uma revisão da literatura relacionada ao tema, emespecial no artigo publicado pelos professores John M.Wright e Marilena Vered no Head & Neck PathologyJournal, no ano de 2017, o qual apresenta as principaisatualizações desde as reuniões de 1992 e 2005. O quefoi excluído da terceira edição, o que foi retomado dasegunda edição, as novas descobertas e o porquê detais mudanças serão alguns pontos abordados. Consideraçõesfinais: observa-se que as atualizações foramorientadas pelos princípios de simplicidade, relevânciaclínica, validade científica e utilidade, no intuito defornecer uma classificação contemporânea e menoscomplexa, servindo como base para o clínico e o patologistaem termos de diagnóstico e condução dos casos. (AU)

Objective: this study aimed to present and discuss the most relevant updates in the 4th classification of head and neck tumors by the World Health Organization (WHO) in 2017, especially for odontogenic tumors. Literature review: the study is based on a literature review related to the topic, particularly on the article published by Professors John M. Wright and Marilena Vered in the Head & Neck Pathology Journal in 2017, which presents the main updates since the meetings of 1992 and 2005. What was excluded from the third edition and resumed from the second one, the new findings and the reason for such changes will be some of the points addressed. Final considerations: it is observed that the updates were guided by the principles of simplicity, clinical significance, and scientific validity and utility, in order to provide a contemporary and simpler classification that works as a basis for practitioners and pathologists in terms of diagnosis and management of cases. (AU)

Expression of proteoglycans in two types of ameloblastoma: novel Immunohistochemical findings.

Alterations in cellular and extracellular matrix components play an important role during tumorigenesis; proteoglycans are included among these components. Ameloblastomas are odontogenic tumors distinguished as invasive and infiltrative neoplasms and are divided into different histological types, the most common of which are the unicystic ameloblastoma and the conventional ameloblastoma. The aim of this study was to identify the presence of two proteoglycans, perlecan and biglycan, in different types of ameloblastoma. Using immunohistochemistry, we determined the presence of both proteins in 28 unicystic ameloblastomas and 23 conventional ameloblastomas. We identified the cytoplasmic and nuclear presence of perlecan and the cytoplasmic presence of biglycan in both types of ameloblastoma. The mean values of immunoexpression were higher in the conventional type compared to the unicystic type. Neither the presence of biglycan in ameloblastomas nor the nuclear presence of perlecan in any odontogenic tumor has previously been reported. The differential immunoexpression of perlecan and biglycan in these types of ameloblastomas suggests their participation in the developmental process of these tumors.

Differential expression of glypican-1 in ameloblastoma variants.

Although benign, ameloblastomas are locally invasive and destructive tumors of the jawbones. The glypicans comprise a family of glycosylphosphatidylinositol-anchored proteoglycans that, by virtue of their cell-surface localization and heparin sulfate chain composition, might regulate the response of cells to numerous heparin-binding growth factors, cell adhesion molecules, and extracellular matrix components. The expression of glypican-1 is differentially altered among different types of malignancies, suggesting a possible role in the tumorigenesis and biological behavior of these neoplasms. The aim of this study was to determine the expression of glypican-1 and then hypothesize the possible role that this protein may play in the biological behavior of ameloblastomas. We assessed the presence of glypican-1 by immunohistochemical staining analyses in a series of 80 cases of different types of ameloblastomas. Desmoplastic ameloblastomas exhibited the highest expression of glypican-1 (100%), followed by the peripheral (66%), solid/multicystic (51.2%), and unicystic (47.2%) types, showing statistically significant differences among them (P<0.001). Differences detected in glypican-1 expression among different subtypes of ameloblastomas, could be suggesting a possible association with their different biological behavior.

Ceratoameloblastoma: uma lesão muito rara com recidiva incomum / Keratoameloblastoma: a very rare lesion with an unusual recurrence

A denominação ceratoameloblastoma tem sido utilizada para descrever um grupo histológico heterogêneo de variantes do ameloblastoma, que tem em comum a formação de ceratina pelo epitélio ameloblastomatoso. Até o momento, vinte casos foram previamente reportados na literautra, dos quais cinco exibem um componente papilifero. Nós relatamos um novo caso de um tumor recidivado que se enquadra no espectro do keratoameloblastoma, o qual apresentava uma lesão expansiva, sólida, com calcificações internas, na fossa infratemporal direita, seis anos após uma hemimandibulectomia ipsilateral, de uma mulher branca de 46 anos. Ilhas de células colunares que lembram ameloblastoma ao redor de uma área central com células estreladas, algumas das quais completamente preenchidas por ceratina e outras exibindo células basais colunares a cuboidais com núcleo hipercromático, foram observadas na avaliação histológica do espécime. Nós revisamos o padrão clínico, histopatológico e radiográfico dos casos previamente publicados de ceratoameloblastoma, além do tratamento e acompanhamento realizado. Embora um pequeno número de casos tenha sido reportado, o comportamento biológico agressivo e altas taxas de recorrência sugerem que um manejo mais agressivo deve ser realizado. Ressecção com margens de segurança e análise histopatológica dessas margens são altamente recomendadas. (AU)

The denomination keratoameloblastoma has been used to describe a histologically heterogeneous group of ameloblastoma variants which have in common the formation of keratin by the ameloblastomatous epithelium. Up to now twenty cases of keratoameloblastoma have been previously reported in the literature, of which five exhibited a papilliferous component. Here we report a new case of a relapsed tumor that fits the spectrum of keratoameloblastoma which presented as an expansile, solid lesion with internal calcification in the right infratemporal fossa six years after ipsilateral hemimandibulectomy of a 46- year-old white female. Islands of columnar cells resembling ameloblasts surrounding a central area with starry cells, some of them completely filled with keratin and others also showing columnar to cuboidal basal cells with hypercromatic nuclei were observed in the histological evaluation of the specimen. The clinical, histopathologic and radiographic features of keratoameloblastoma are reviewed so as treatment and follow up. Although only few cases have been reported, the biological aggressive behavior and the high recurrence suggest that a more aggressive approach should be performed. A resection with sufficient safety margins and histopathological analysis of surgical margins are highly recommended. (AU)

Avaliação da expressão imuno-histoquímica das proteínas p53 e pRB em ameloblastomas e tumores odontogênicos queratocísticos / Evaluation of immunohistochemistry expression of the proteins p53 and pRB in ameloblastomas and keratocystic odontogenic tumorP

Tumores odontogênicos constituem grupo abrangente de afecções tumorais, sendo ameloblastomas e tumores odontogênicos queratocísticos as lesões benignas de maior frequência, cujas características biológicas são pouco conhecidas. Objetivo do presente estudo foi avaliar o perfil imuno-histoquímico das proteínas pRB e p53 em ameloblastoma e tumor odontogênico queratocístico. Foram avaliadas amostras de material parafinado de 21 casos de ameloblastoma e de 20 casos de tumor odontogênico queratocístico para ensaio de imuno-histoquímica com os anticorpos anti-pRB e anti-p53. A contagem da imuno-marcação foi realizada a partir de fotografias de alta resolução processadas no software ImageJ para quantificação manual em campo de 1000 células. A localização da imuno-marcação para ambos anticorpos foi semelhante, sendo em ameloblastomas predominantemente nas células da periferia e, em tumores odontogênicos queratocísticos, nas camadas suprabasais. Quantitativamente, as porcentagens de células marcadas foram estatisticamente maior nos ameloblastoma para anti-p53 (p=0,01) e maior nos tumores odontogênicos queratocísticos para anti-pRB (p=0,04). Não houve correlação estatística entre a porcentagem de células marcadas para anti-p53 e anti-pRB nos ameloblastomas, porém, esta correlação foi positiva e moderada nos tumores odontogênicos queratocísticos (r=0,537; p=0,018). Nota-se ligeira diferença na quantificação das imuno-marcações para o anti-p53 e anti-pRB. Tais resultados devem ser ponderados pela reduzida casuística, porém, sugerem perfis distintos em mecanismos biológicos determinantes para ambos os tumores.

Odontogenic tumors are a comprehensive group of tumor diseases, being ameloblastomas and keratocystic odontogenic tumors the most frequent benign odontogenic tumors. Their biological characteristics are little unknown. The aim of present study was to evaluate the immunohistochemical profile of pRB and p53 proteins in 21 cases of ameloblastomas and 20 cases of keratocystic odontogenic tumors for anti-pRB and anti-p53 antibodies. The quantification of immunostaining was performed manually with high-resolution photographs processed in the ImageJ software to quantify positive cells in a 1000 cells-field. The location of immunostaining for both antibodies was similar. In ameloblastomas, positive cells are located mainly in the peripheral layers, whereas in keratocystic odontogenic tumors the positive cells are located in the suprabasal layers. Quantitatively, the percentage of labeled cells was statistically higher in ameloblastomas for anti-p53 (p = 0.01) and higher in keratocystic odontogenic tumors for anti-pRB (p = 0.04). There was no statistical correlation between the percentage of labeled cells to anti-p53 and anti-pRB in ameloblastomas, however, its correlation was positive and moderate in keratocystic odontogenic tumors (r = 0.537; p = 0.018). It is possible to identify a slight difference in immuno-quantification for anti-p53 and anti-pRB among these lesions. These results must be pondered by the small sample, however, is suggests a different profile in a preponderant key biological mechanisms for odontogenic tumors.

Expresión inmunohistoquímica de PCNA, Ki-67 y ciclina D1 en ameloblastomas multiquísticos / Immunohistochemical expression of PCNA, Ki-67 and cyclin D1 in solid ameloblastomas

Introducción: el ameloblastoma es un tumor odontogénico benigno, localmente agresivo, que debe su origen a partir de estructuras epiteliales involucradas en la odontogénesis. El objetivo del presente trabajo es identificar, por medio de técnicas inmunohistoquímicas, aspectos de los mecanismos regulatorios de proliferación celular y la relación de los diferentes subtipos histológicos con el comportamiento biológico de estos tumores. Materiales y métodos: se seleccionaron 10 ameloblastomas multiquísticos en los cuales se realizó inmunotinción con los marcadores PCNA, Ki-67 y Ciclina D1. La interpretación de las tinciones se basó en la intensidad, localización y los subtipos celulares. La valoración utilizada para contabilizar el número de células fue baja (menos del 10 por ciento), media (hasta el 50 por ciento) y alta (más del 50 por ciento). Resultados: la tinción fue positiva en 6 casos para PCNA, en 3 para Ki-67 y en 5 para ciclina D1, en las células basales periféricas, en los patrones foliculares y plexiformes, en las del esbozo del retículo estrellado y fue negativa en los patrones quísticos y acantomatosos. Conclusión: en base a los hallazgos se puede asumir que las células basales y parabasales de los patrones foliculares y plexiformes presentan mayor actividad proliferativa que otros patrones y determinarían la evolución y tratamiento (AU)

Expressão imuno-histoquímica da Axina1, GSK3 ß, APC e via Wnt1 nos ameloblastomas / Expression immunohistochemistry of Axina1, GSK3 ß, APC e Wnt1 signaling in ameloblastomas

Os ameloblastomas são tumores odontogênicos, de origem epitelial, que demonstra crescimento lento e comportamento invasivo e altamente recidivante. No entanto os mecanismos moleculares e as vias de sinalização celulares envolvidas na progressão desse tumor não estão claros. Estudos relatados na literatura indicam que aberrações nas vias de sinalização similares as encontradas durante o desenvolvimento dentário, incluindo a via Wnt1 e as proteínas GSK3 ß, APC e Axina1, que formam o complexo de degradação da ß-catenina podem estar alteradas nos ameloblastomas, levando a proliferação e progressão tumoral. O objetivo deste trabalho foi analisar a relação da expressão das proteínas Wnt1, GSK3 ß, APC e Axina1 com a proliferação tumoral dos ameloblastomas por meio de reações de imuno-histoquímicas. Para este estudo foram selecionados 40 casos com o diagnóstico de ameloblastoma, pertencentes aos arquivos do Serviço de Patologia da Disciplina de Patologia Bucal da FOUSP e utilizada a técnica imunohistoquimica da estreptavidina-biotina em blocos parafinados destes casos selecionados. Nos resultados foram observados marcações positivas para a proteína Wnt1 em 25 (62,5%) casos, Axina1 em 23(57,5%), APC de 26(65%) casos e GSK3 ß em 34(85%) casos.

Ameloblastomas is an odontogenic tumors of epithelial origin, which shows slow-growing, highly invasive and recurrent behavior. Nevertheles the molecular mechanisms and cellular signaling pathways involved in the progression of this tumour are not yet clear. Reported studies in leterature indicates that aberrations in signaling pathways similar to those found during tooth development, including Wnt1 and GSK3 ß pathways, APC and Axin1 proteins which form the ß-catenin degradation complex may be altered in ameloblastoma, leading to proliferation and tumour progression. The aim of this study was to analyze the relationship between the expression of Wnt1, GSK3 ß, APC and Axin1 proteins with the tumour proliferation in ameloblastomas by immunohistochemical reactions. For this study, 40 cases were selected with the diagnosis of ameloblastoma, from the Oral Pathology department archives, Dental School, University of São Paulo and the immunohistochemistry technique of streptavidin-biotin in paraffin blocks of these selected cases was perfomed. Positive results to the Wnt protein were observed in 25 (62.5%) cases, Axina1 in 23 (57.5%), APC of 26 (65%) cases and GSK3 ß in 34 (85%) cases.

Expresión inmunohistoquímica de PCNA, Ki-67 y ciclina D1 en ameloblastomas multiquísticos / Immunohistochemical expression of PCNA, Ki-67 and cyclin D1 in solid ameloblastomas

Introducción: el ameloblastoma es un tumor odontogénico benigno, localmente agresivo, que debe su origen a partir de estructuras epiteliales involucradas en la odontogénesis. El objetivo del presente trabajo es identificar, por medio de técnicas inmunohistoquímicas, aspectos de los mecanismos regulatorios de proliferación celular y la relación de los diferentes subtipos histológicos con el comportamiento biológico de estos tumores. Materiales y métodos: se seleccionaron 10 ameloblastomas multiquísticos en los cuales se realizó inmunotinción con los marcadores PCNA, Ki-67 y Ciclina D1. La interpretación de las tinciones se basó en la intensidad, localización y los subtipos celulares. La valoración utilizada para contabilizar el número de células fue baja (menos del 10 por ciento), media (hasta el 50 por ciento) y alta (más del 50 por ciento). Resultados: la tinción fue positiva en 6 casos para PCNA, en 3 para Ki-67 y en 5 para ciclina D1, en las células basales periféricas, en los patrones foliculares y plexiformes, en las del esbozo del retículo estrellado y fue negativa en los patrones quísticos y acantomatosos. Conclusión: en base a los hallazgos se puede asumir que las células basales y parabasales de los patrones foliculares y plexiformes presentan mayor actividad proliferativa que otros patrones y determinarían la evolución y tratamiento

Recurrencia luego de tratamiento conservador de ameloblastoma mandibular: reporte de casos / Recurrence after conservative treatment of mandibular ameloblastoma: case reports

el propósito de este estudio fue analizar, en base a la presentación de casos clínicos recibidos en el Servicio de Cirugía de Cabeza y Cuello del Hospital Córdoba (Córdoba, argentina), lostratamientos conservadores de enucleación más curetaje) de los ameloblastomas mandibulares con sus resultados de recurrencia. además, se realizó revisión de la literatura actual sobre los tratamientos conservadores de dicha patología con sus efectos.(AU)

Recurrencia luego de tratamiento conservador de ameloblastoma mandibular: reporte de casos / Recurrence after conservative treatment of mandibular ameloblastoma: case reports

el propósito de este estudio fue analizar, en base a la presentación de casos clínicos recibidos en el Servicio de Cirugía de Cabeza y Cuello del Hospital Córdoba (Córdoba, argentina), lostratamientos conservadores de enucleación más curetaje) de los ameloblastomas mandibulares con sus resultados de recurrencia. además, se realizó revisión de la literatura actual sobre los tratamientos conservadores de dicha patología con sus efectos.

Solid ameloblastomas - Retrospective clinical and histopathologic study of 54 cases.

UNLABELLED: Recently, the World Health Organization (WHO) excluded the desmoplastic pattern from the histopathological spectrum of solid ameloblastomas and classified it as a distinct variant, named desmoplastic ameloblastoma. AIM: To perform a retrospective analysis of the clinicopathologic aspects in a case series of solid ameloblastomas. STUDY DESIGN: Cross-sectional cohort study. MATERIALS AND METHODS: Data regarding age, gender, location and clinical characteristics were retrieved from patient records. Histological sections were evaluated regarding existing histological patterns and the predominant histological pattern. Cases were classified according to the study of Waldron and El-Mofty (1987) and the WHO classification of 2005. RESULTS: A total of 54 cases were identified, with similar gender distribution and a mean age of 38.3 years. Fifty three cases (98.1%) affected the mandible. Forty nine cases (90.8%) were classified as solid ameloblastomas, 3 (5.6%) as desmoplastic ameloblastomas, and 2 (3.7%) as hybrid lesions. The most frequent histological patterns in solid ameloblastomas were follicular (77.6%), acanthomatous (69.4%), and plexiform (65.3%). Focal areas of desmoplastic ameloblastomas were identified in 11 solid ameloblastomas (22.4%). CONCLUSION: Despite its characterization as a distinct variant, our results revealed that focal areas of desmoplastic ameloblastomas can be observed with some frequency in conventional ameloblastomas.

Ameloblastomas sólidos: estudo retrospectivo clínico e histopatológico em 54 casos / Solid ameloblastomas: retrospective clinical and histopathologic study of 54 cases

Recentemente, a Organização Mundial da Saúde (OMS) excluiu o padrão desmoplásico do espectro histopatológico do ameloblastomas sólidos e o enquadrou como uma variante distinta, designada ameloblastoma desmoplásico. OBJETIVO: Analisar os achados clínico-patológicos em uma série de casos de ameloblastomas sólidos. FORMA DE ESTUDO: Estudo de coorte transversal. MATERIAL E MÉTODO: Dados sobre idade, sexo, localização e características clínicas foram obtidos em fichas de biópsia. Cortes histológicos foram avaliados quanto aos padrões histológicos existentes e o padrão histológico predominante. Os casos foram classificados com base no estudo de Waldron e El-Mofty (1987) e na classificação da OMS de 2005. RESULTADOS: Foram identificados 54 casos, com distribuição similar entre os sexos e média de idade de 38,3 anos. Cinquenta e três casos (98,1 por cento) afetaram a mandíbula. Quarenta e nove casos (90,8 por cento) foram classificados como ameloblastomas sólidos, 3 (5,6 por cento) como ameloblastomas desmoplásicos e 2 (3,7 por cento) como lesões híbridas. Os padrões histológicos folicular (77,6 por cento), acantomatoso (69,4 por cento) e plexiforme (65,3 por cento) foram os mais frequentes nas lesões sólidas. Áreas focais de ameloblastoma desmoplásico foram identificadas em 11 ameloblastomas sólidos (22,4 por cento). CONCLUSÃO: Embora enquadrado como uma variante distinta, nossos resultados revelam que áreas focais de ameloblastoma desmoplásico podem ser identificadas com relativa frequência em ameloblastomas convencionais.

Recently, the World Health Organization (WHO) excluded the desmoplastic pattern from the histopathological spectrum of solid ameloblastomas and classified it as a distinct variant, named desmoplastic ameloblastoma. AIM: To perform a retrospective analysis of the clinicopathologic aspects in a case series of solid ameloblastomas. STUDY DESIGN: Cross-sectional cohort study. MATERIALS AND METHODS: Data regarding age, gender, location and clinical characteristics were retrieved from patient records. Histological sections were evaluated regarding existing histological patterns and the predominant histological pattern. Cases were classified according to the study of Waldron and El-Mofty (1987) and the WHO classification of 2005. RESULTS: A total of 54 cases were identified, with similar gender distribution and a mean age of 38.3 years. Fifty three cases (98.1 percent) affected the mandible. Forty nine cases (90.8 percent) were classified as solid ameloblastomas, 3 (5.6 percent) as desmoplastic ameloblastomas, and 2 (3.7 percent) as hybrid lesions. The most frequent histological patterns in solid ameloblastomas were follicular (77.6 percent), acanthomatous (69.4 percent), and plexiform (65.3 percent). Focal areas of desmoplastic ameloblastomas were identified in 11 solid ameloblastomas (22.4 percent). CONCLUSION: Despite its characterization as a distinct variant, our results revealed that focal areas of desmoplastic ameloblastomas can be observed with some frequency in conventional ameloblastomas.

Clinicopathological study and treatment outcomes of 121 cases of ameloblastomas.

The aim of this paper is to evaluate the clinical, radiographic, and histopathological findings and treatment modalities in all cases of ameloblastomas treated at the Sao Paulo Cancer Hospital, between 1953 and 2003. 121 case reports were retrieved from the medical files. Data were reviewed and statistical analysis was performed using Kaplan-Meyer method and Cox proportional risk model. The patients' age ranged from 2 to 82 years (mean 33.2 years), with a slight female prevalence. Most cases were located in the posterior mandible (80%). Radiographically, 60% showed a multilocular pattern. 113 casees were solid ameloblastomas, and plexiforme subtype was the most common. Solid tumours were treated by wide resection, curettage and criosurgery, or curettage alone, and unicystic tumours by curettage and/or cryotherapy. The global mean recurrence rate was 22%, with a mean follow-up of 9.7 years. The ameloblastomas were predominantly solid, affecting the posterior mandible. Important factors for outcome were radiographically multilocular lesions, the presence of ruptured basal cortical bone and histologically follicular tumours.

Assessment of computerized tomography density patterns of ameloblastomas and keratocystic odontogenic tumors.

The aim of this study was to evaluate computerized tomography (CT) density patterns of solid ameloblastomas (SA), unicystic ameloblastomas (UA), and sporadic and multiple keratocystic odontogenic tumors (SK and MK, respectively). A region of interest (ROI) was delimited corresponding to almost the entire lesional area on each axial slice of 25 CT exams. For each ROI, CT values (HU(ROI)) and heterogeneity (HTG(ROI)) were recorded and compared among lesion groups as well as among central and peripheral slices of the same lesion. The average HU(ROI) were: SA 35.9 +/- 12.6; UA 31.0 +/- 6.0; SK 28.4 +/- 10.5; and MK 30.5 +/- 20.6. SK and MK had the lowest CT values and highest heterogeneity. SA and UA did not show statistical difference for HU(ROI). However, SA had greater HTG(ROI) values. SA presented a different pattern when the central slices were compared with the peripheral slices. HU(ROI) was higher, whereas HTG(ROI) was lower, among the central slices of SA.

Ameloblastoma desmoplásico: diagnóstico precoz: presentación de un caso clínico / Desmoplastic ameloblastoma: early diagnosis: report of a clinical case

El ameloblastoma es una neoplasia benigna, localmente invasora, originada a partir de restos de epitelio odontogénico o del revestimiento epitelial de un quiste dentígero. Es la neoplasia odontogénica más frecuente de la mandíbula. Actualmente la OMS reconoce 4 tipos de ameloblastomas: el sólido multiquístico, el periférico o extraóseo, el desmoplásico y el uniquístico. El tipo desmoplásico es poco frecuente y presenta características clínicas, radiográficas e histológicas distintivas , aunque su comportamiento es similar al del tipo sólido-multiquístico, por lo que el tratamiento quirúrgico recomendado no varía. Se presenta un caso clínico donde el diagnóstico precoz fue fundamental para realizar un tratamiento conservador, rápido y con mínimas consecuencias estéticas y psicológicas para el paciente.(AU)

Ameloblastoma desmoplásico: diagnóstico precoz: presentación de un caso clínico / Desmoplastic ameloblastoma: early diagnosis: report of a clinical case

El ameloblastoma es una neoplasia benigna, localmente invasora, originada a partir de restos de epitelio odontogénico o del revestimiento epitelial de un quiste dentígero. Es la neoplasia odontogénica más frecuente de la mandíbula. Actualmente la OMS reconoce 4 tipos de ameloblastomas: el sólido multiquístico, el periférico o extraóseo, el desmoplásico y el uniquístico. El tipo desmoplásico es poco frecuente y presenta características clínicas, radiográficas e histológicas distintivas , aunque su comportamiento es similar al del tipo sólido-multiquístico, por lo que el tratamiento quirúrgico recomendado no varía. Se presenta un caso clínico donde el diagnóstico precoz fue fundamental para realizar un tratamiento conservador, rápido y con mínimas consecuencias estéticas y psicológicas para el paciente.

Odontogenic tumors: clinical and pathology study of 238 cases.

UNLABELLED: Odontogenic tumors are neoplasms that develops exclusively in the gnathic bones; they originate from odontogenic tissues, by epithelial or mesenchymal proliferation, or both. AIM: To evaluate the incidence of odontogenic tumors in a specific institution, and to compare these findings with other studies in the literature. STUDY FORMAT: A cross-sectional cohort retrospective study. MATERIAL AND METHOD: The sample was obtained from the files of patients with odontogenic tumors diagnosed between January 1992 and March 2007 (15 years). Cases in which the diagnosis could be adapted to the new World Health Organization (WHO) of 2005 were included. Data such as gender, age, anatomical site, histological type and symptomatology were analyzed. RESULTS: Odontogenic tumors were 4.76% of all biopsied lesions within the studied period. The mean age was 30.7 years; 57% of the patients were male. The keratocystic odontogenic tumor was the most prevalent histological type (30%), followed by the ameloblastoma (23,7%). The rate of asymptomatic cases was 75.7%. CONCLUSION: Odontogenic tumors occurred more frequently in females, in the second and third decades of life, and more commonly in the mandible; most cases were asymptomatic.

Estudo retrospectivo dos casos diagnosticados como ameloblastoma no Serviço de Anatomia Patológica do Hospital Universitário Antônio Pedro entre 1997 e 2007 / A retrospective study of ameloblastoma in the Anatomic Pathology Service of Antônio Pedro University Hospital between 1997 and 2007

INTRODUÇÃO: O ameloblastoma é um tumor odontogênico de origem epitelial que, pela freqüência, subtipos clínicos, grande capacidade infiltrativa e alta tendência à recorrência tem merecido bastante atenção. OBJETIVO:Realizar estudo retrospectivo dos casos diagnosticados histopatologicamente de ameloblastoma no Serviço de Anatomia Patológica do Hospital Universitário Antônio Pedro da Universidade Federal Fluminense (HUAP/UFF) no período de 1997 a 2007. Material e métodos: Foram selecionados casos de ameloblastoma correspondentes ao período da pesquisa, e dados como idade, sexo, raça, localização da lesão, aspecto radiográfico, tipo de biópsia, diagnósticos clínico e histopatológico foram compilados das fichas de requisição e/ou prontuários. RESULTADOS:Depois do levantamento e da revisão das lâminas para confirmação do diagnóstico de ameloblastoma, a amostra totalizada foi de 23 casos. Os pacientes mais acometidos eram do sexo masculino, leucodermas e estavam entre a primeira e a terceira década de vida. Todos os casos ocorreram na mandíbula, sendo a região posterior a mais afetada. Predominaram o aspecto radiográfico multilocular e, histopatologicamente, o padrão multicístico, sendo os subtipos folicular e híbrido os mais freqüentes. Não foram observados casos de ameloblastoma desmoplásico e de células basais. CONCLUSÕES: A freqüência do ameloblastoma varia de acordo com a região geográfica avaliada, e a realização de estudos retrospectivos pode contribuir para a identificação de grupos e dos possíveis fatores associados ao seu desenvolvimento.

BACKGROUND: Ameloblastoma is an odontogenic tumor of epithelial origin that has received considerable attention due to its frequency, clinical subtypes and high tendency to infiltrate and recur. OBJECTIVE: To perform a retrospective study of cases histopathologically diagnosed of ameloblastoma at the Pathological Anatomy Department of APUH/UFF-RJ from 1997 to 2007. Material and methods: We selected cases of ameloblastoma corresponding to the period of this research. Data such as age, gender, race, location of lesion, radiographic features, type of biopsy, clinical diagnosis, and histopathological diagnosis were compiled from patients' records. RESULTS:After the investigation and review of slides for confirmation of the diagnosis of ameloblastoma, the sample comprised 23 cases. Most patients with ameloblastoma were male, Caucasian and age range 10-30. All lesions were in the mandible, mainly in the posterior region. The multilocular radiographic types were predominant, and histopathologically, multicystic type, whereas the follicular and hybrid ones were more frequent. There were no cases of desmoplastic and basal cells ameloblastoma. CONCLUSIONS:The frequency of ameloblastoma varies according to geographic analyzed region, and retrospective studies can contribute to identify groups and possible factors associated with its development.

Tumores odontogênicos: estudo clínico-patológico de 238 casos / Odontogenic tumors: clinical and pathology study of 238 cases

Os tumores odontogênicos são neoplasias que se desenvolvem exclusivamente nos ossos gnáticos, originando-se dos tecidos odontogênicos por proliferação de tecido epitelial, mesenquimal ou ambos. OBJETIVO: Avaliar a incidência de tumores odontogênicos em determinada instituição e comparar com outros estudos da literatura mundial. FORMA DE ESTUDO: Estudo de coorte transversal. MATERIAL E MÉTODO: O material do estudo foi levantado a partir dos registros de pacientes com tumores odontogênicos, no período de janeiro de 1992 a março de 2007 (15 anos). Foram incluídos os casos de pacientes que se enquadravam na Classificação Histológica da Organização Mundial de Saúde (OMS) de 2005. Foram analisados os indicadores gênero, faixa etária, localização anatômica, tipo histológico e presença de sintomatologia. RESULTADOS: Os tumores odontogênicos constituíram 4,76 por cento dentre todas as lesões biopsiadas dentro do período estudado. A idade média dos pacientes foi de 30,7 anos, 57 por cento dos pacientes eram do gênero masculino. O tumor odontogênico ceratocístico foi o tipo histológico mais prevalente (30 por cento), seguido do ameloblastoma (23,7 por cento). Quanto à presença de sintomatologia, 75,7 por cento dos casos apresentaram-se assintomáticos. CONCLUSÃO: Os tumores odontogênicos parecem ter discreta predileção pelo gênero feminino, segunda e terceira décadas de vida, sendo mais freqüentes na mandíbula e, na maioria dos casos apresentam-se assintomáticos.

Odontogenic tumors are neoplasms that develops exclusively in the gnathic bones; they originate from odontogenic tissues, by epithelial or mesenchymal proliferation, or both. AIM: To evaluate the incidence of odontogenic tumors in a specific institution, and to compare these findings with other studies in the literature. STUDY FORMAT: A cross-sectional cohort retrospective study. MATERIAL AND METHOD: The sample was obtained from the files of patients with odontogenic tumors diagnosed between January 1992 and March 2007 (15 years). Cases in which the diagnosis could be adapted to the new World Health Organization (WHO) of 2005 were included. Data such as gender, age, anatomical site, histological type and symptomatology were analyzed. RESULTS: Odontogenic tumors were 4.76 percent of all biopsied lesions within the studied period. The mean age was 30.7 years; 57 percent of the patients were male. The keratocystic odontogenic tumor was the most prevalent histological type (30 percent), followed by the ameloblastoma (23,7 percent). The rate of asymptomatic cases was 75.7 percent. CONCLUSION: Odontogenic tumors occurred more frequently in females, in the second and third decades of life, and more commonly in the mandible; most cases were asymptomatic.