Can ameloblastomas arise from odontogenic keratocysts?

O ameloblastoma é um tumor odontogênico localmente agressivo, com altas taxas de recorrência. Raramente o ameloblastoma apresenta aspecto histológico semelhante ao queratocisto odontogênico devido à presença de áreas queratinizadas. O objetivo deste estudo é relatar um caso de ameloblastoma na mandíbula, diagnosticado e tratado incorretamente como um queratocisto odontogênico devido a características macroscópicas incomuns e aspectos histológicos raros que prejudicaram um correto diagnóstico. Relato de caso: Paciente do sexo feminino, 57 anos, apresentando lesão assintomática no ângulo mandibular esquerdo tratado inicialmente com biópsia incisional e descompressão. Os achados histológicos mostraram um aspecto sugestivo de queratocisto odontogênico. No pós operatório de 3 anos, a paciente retornou com uma nova lesão no lado esquerdo da mandíbula e foi então submetida a curetagem. Desta vez, as seções histológicas mostraram um padrão de ameloblastoma e, devido a este fato, a paciente permaneceu com um seguimento de 6 meses. No pós operatório de 4 anos da segunda operação, a paciente retornou apresentando nova recidiva. A biópsia mostrou um ameloblastoma e a mesma foi submetida a ressecção mandibular e reconstrução como tratamento. Após o procedimento final, a recuperação foi sem intercorrências e a paciente passou por um pós-operatório de quatro anos sem recidivas. Conclusão: Este caso destaca a importância de se realizar uma biópsia e um exame adequado por profissional especializado, devido à possibilidade de lesões atípicas que ocorrem restritas à região da cabeça e pescoço.The ameloblastoma is a locally aggressive odontogenic tumour that has high recurrence rates. It rarely presents a histological aspect similar to the odontogenic keratocyst, because of the presence of keratinised areas. This study aimed to report a case of ameloblastoma in the mandible, diagnosed and treated incorrectly as an odontogenic keratocyst because of unusual macroscopic characteristics and rare histological aspects that impaired a correct diagnosis. Case report: A 57-year-old female patient, presenting an asymptomatic lesion at the left mandibular angle, was treated by incisional biopsy and decompression. The histological sections showed an aspect suggesting odontogenic keratocyst. At the 3-year postoperative period, the patient returned with a new lesion on the left side of the mandible and was then subjected to curettage. The histological sections showed a pattern of ameloblastoma and, because of this, the patient remained with a 6-month follow-up. At the 4-year postoperative period after the second operation, the patient returned with a new recurrence. The biopsy showed an ameloblastoma and the patient was submitted to mandibular resection and reconstruction as treatment. After the final procedure, the recovery was uneventful and the patient is now undergoing a postoperative period of four years, without recurrences. Conclusion: This case highlights the importance of carrying out a proper biopsy and an adequate examination by a specialised professional, because of the possibility of atypical lesions occurring restricted to the head and neck region.

Pigmented squamous cell carcinoma in situ : report of a new case and review of the literature

Pigmented squamous cell carcinoma in situ (PSCCIS) is very rare, being clinically described as a pigmented lesion with histological characteristics of an in-situ carcinoma presenting pigmentation within neoplastic cells. A 50-year-old Afro-descendant man came for clinical evaluation of a painful black and red lesion located on the right aspect of the oropharyngeal isthmus. After incisional biopsy, the resulting sample was described as a pigmented squamous cell carcinoma in situ, a diagnosis further confirmed by immunohistochemical analysis. Treatment consisted in total excision of the lesion, and no recurrence was observed after a 30-month follow-up. Clinicians and pathologists should be aware of PSCCIS as a differential diagnosis of melanoma, a lesion which significantly increases the morbidity and mortality rates among these patients

Peripheral Calcifying Epithelial Odontogenic Tumour Mimicking a Gingival Inflammation: A Diagnostic Dilemma

The calcifying epithelial odontogenic tumour (CEOT) is an extremely rare benign neoplasia, accounting for approximately 1% of all odontogenic tumours. CEOT can have two clinical manifestations: central or intraosseous (94% of the cases) and peripheral or extraosseous (6% of the cases). Although the latter is less common, the peripheral variant has been described as an insidious lesion, since it is usually asymptomatic and may be erroneously mistaken with gingival hyperplasia, hamartomas, or even metastasis of malignant neoplasia. We report a case of a young male patient presenting with a peripheral CEOT in the mandibular posterior region, mimicking a located gingival inflammation

Imunonhistochemical analysis of BRAF V600E mutation in ameloblastomas

O ameloblastoma é um tumor odontogênico agressivo, localmente invasivo e altamente recorrente. Estudos demonstram que é a neoplasia odontogênica benigna mais comum e eventualmente pode apresentar comportamento de lesões malignas. A detecção da mutação BRAF V600E tem sido demonstrada como uma das principais vias de proliferação tumoral dos ameloblastomas. Portanto, a identificação desses marcadores poderão ser úteis para elaborar estratégias mais eficientes de tratamento dessa patologia, bem como melhorar a qualidade de vida dos pacientes. Este estudo pesquisou a mutação BRAF V600E, por meio da técnica de imunohistoquimica, em ameloblastomas mandibulares bem como correlacionou com dados clínicos e imaginológicos relevantes. A amostra consistiu de 84 casos diagnosticados como ameloblastoma e localizados na mandíbula dos acervos do Serviço de Patologia Cirúrgica do Departamento de Estomatologia da FOUSP e do Serviço de Cirurgia Bucomaxilofacial do Hospital Erasto Gaertner, Curitiba, PR. Os blocos obtidos foram submetidos a reação imunohistoquímica para detectar a mutação da proteína BRAF e foram coletados todos os dados clínicos e imaginológicos dos pacientes como sexo, idade, tamanho do tumor, localização mandibular, aspecto radiográfico, tipo e subtipo histológico e status do tumor. Análise estatística foi realizada buscando estabelecer correlação entre o marcador BRAF e dados clínicos e imaginológicos. Como resultados, dos 84 pacientes, 44 eram pacientes do sexo masculino (52,38%) e 40 feminino (47,62%). A mediana da idade encontrada foi de 25,5 anos sendo que em 42 casos foi observada idade inferior a mediana (50%) e 42 superior (50%). Com relação a presença ou ausência da mutação BRAF V600E, 66 casos apresentaram positividade para o marcador estudado (78,57%) e 18 foram negativos (21,43%). Ao relacionar a expressão de BRAF com as variáveis, foi observado significância estatística para a variável localização (P= 0,0353) e tamanho do tumor (P=0,008). Não foi observado resultados com significância estatística com relação às variáveis sexo (P=0,969), idade (P=1,0), aspecto radiográfico (P=0,977), padrão histológico (P=0,910), subtipo histológico (P=0,5141) e status do tumor (P=0,336). Os autores concluíram que a mutação BRAF V600E é comum em ameloblastomas mandibulares e é mais frequente tumores maiores de 4 cm e na região posterior de mandíbula. Além disso, independe do tipo histológico do tumor, idade e sexo do paciente, aspecto radiográfico e status do tumor (primário x recorrente).Ameloblastoma is an aggressive odontogenic tumour, being locally invasive and highly recurrent. Studies have demonstrated that it is the most common benign odontogenic neoplasia, sometimes exhibiting behaviour of malignant lesions. Detection of BRAF V600E mutation has been shown to be one of the main proliferation pathways of ameloblastomas. Therefore, the identification of these markers can be useful to elaborate more efficient treatment strategies for this pathology as well as to improve the patient\'s quality of life. This study investigated the BRAF V600E mutation in mandible ameloblastomas by using the immunohistochemical technique and by correlating clinical and imaging data of the patients. The sample consisted of 84 cases diagnosed as mandibular ameloblastoma, with all blocks being obtained from the Surgery Pathology Service of the FOUSP Department of Stomatology and the Maxillofacial Surgery Unit of the Erasto Gaertner Hospital, Curitiba, PR. The blocks were submitted to immunohistochemical reaction for detection of BRAF protein mutation, with clinical and imaging data such as age, gender, tumour size, mandibular location, radiographic aspect, histological type and subtype, and tumour status were collected. Statistical analysis was performed in order to establish a correlation between BRAF marker and clinical and imaging data. The results showed that, of the 84 patients, 44 were male (52.38%) and 40 female (47.62%). The median age was 25.5 years old, with 42 cases having age below the median (50%) and 42 above it (50%). With regard to the presence or absence of BRAF V600E mutation, 66 cases were found to be positive for the marker (78.57%) and 18 were negative (21.43%). The correlation between BRAF expression and variables showed statistical significances for mandibular location (P = 0.0353) and tumour size (P = 0.008), whereas no statistical significance was observed for gender (P = 0.969), age (P = 1.0), radiographic aspect (P = 0.977), histological pattern (P = 0.910), histological subtype (P = 0.5141) and tumour status (P = 0.336). The authors concluded that BRAF V600E mutation is common in mandibular ameloblastomas, with tumours larger than four cm being more frequent in the posterior region of the mandible. In addition, this pathology occurs regardless of histological type of the tumour, age, gender, radiographic aspect and tumour status

Oral inverted ductal papilloma: not related to HPV

Oral inverted ductal papilloma (OIDP) is a rare, nonrecurrent,benign lesion of salivary glands. The etiologyis still poorly understood; the correlation with humanpapilloma virus (HPV) is controversial. Herein wepresent a 74-year-old man with a tumor in lower lip.Incisional biopsy was performed and the histologicaldiagnosis was OIDP. Inno-LiPA assay, based onpolymerase chain reaction and in situ hybridizationwas used to assess for HPV with no detection of viralDNA. Surgical excision was performed without anyrecurrences after two years of follow-up

Oral inverted ductal papilloma: not related to HPV

Oral inverted ductal papilloma (OIDP) is a rare, nonrecurrent,benign lesion of salivary glands. The etiologyis still poorly understood; the correlation with humanpapilloma virus (HPV) is controversial. Herein wepresent a 74-year-old man with a tumor in lower lip.Incisional biopsy was performed and the histologicaldiagnosis was OIDP. Inno-LiPA assay, based onpolymerase chain reaction and in situ hybridizationwas used to assess for HPV with no detection of viralDNA. Surgical excision was performed without anyrecurrences after two years of follow-up

Peripheral Calcifying Epithelial Odontogenic Tumour Mimicking a Gingival Inflammation: A Diagnostic Dilemma

The calcifying epithelial odontogenic tumour (CEOT) is an extremely rare benign neoplasia, accounting for approximately 1% of all odontogenic tumours. CEOT can have two clinical manifestations: central or intraosseous (94% of the cases) and peripheral or extraosseous (6% of the cases). Although the latter is less common, the peripheral variant has been described as an insidious lesion, since it is usually asymptomatic and may be erroneously mistaken with gingival hyperplasia, hamartomas, or even metastasis of malignant neoplasia. We report a case of a young male patient presenting with a peripheral CEOT in the mandibular posterior region, mimicking a located gingival inflammation

Líquen plano oral (LPO): diagnóstico clínico e complementar Oral lichen planus (OLP): clinical and complementary diagnosis

O líquen plano é uma desordem comum do epitélio escamoso estratificado que acomete as mucosas oral e genital, a pele, as unhas e o couro cabeludo. O líquen plano oral (LPO) afeta mulheres de meiaidade e apresenta padrões e distribuição característicos, como estriações brancas, pápulas ou placas brancas, eritema, erosões e bolhas, que podem estar associadas a medicações e/ou materiais dentários no paciente. O diagnóstico clínico somente poderá ser feito se a doença apresentar padrões clássicos, como lesões concomitantes na mucosa oral e na pele. O diagnóstico laboratorial por meio do exame histopatológico se caracteriza pela presença de projeções do epitélio em forma de dentes de serra e corpos de Civatte, e possibilita excluir condições de displasia e malignidade. A imunofluorescência direta é utilizada em suspeita de outras doenças, como pênfigo e penfigoide. O LPO é tratado com agentes anti-inflamatórios, principalmente, corticosteroides tópicos, e novos agentes e técnicas têm-se demonstrado eficazes. A transformação maligna do LPO e sua incidência exata permanecem controversas. Este trabalho tem como objetivo apresentar, com base na revisão da literatura, a etiopatogenia, o diagnóstico clínico, exames complementares e complicações do LPO.<br>Lichen planus is a common disorder of the stratified squamous epithelium that affects oral and genital mucous membranes, skin, nails, and scalp. Oral Lichen Planus (OLP) affects middle-aged women and shows distribution patterns and characteristics such as white striations, white plaques or papules, erythema, blisters and erosions, and may be associated with medication and/or dental materials used by the patient. The clinical diagnosis can only be made if the disease presents classical patterns such as concomitant lesions in the oral mucosa and skin. The laboratory diagnosis is histopathologically characterized by the presence of projections of the epithelium in the form of sawtooth and Civatte bodies and allows the exclusion of dysplasia and malignancy. Direct immunofluorescence is used when there is suspicion of other diseases, such as pemphigus and pemphigoid. OLP is treated with anti-inflammatory agents, particularly topical corticosteroids; new agents and techniques have proved effective. The malignant transformation of OLP and its exact incidence remain controversial. This work aims at presenting, through literature review, the etiopathogenesis, clinical diagnosis, laboratory tests, and complications of OLP