Revisiting the metallothionein genes polymorphisms and the risk of oral squamous cell carcinoma in a Brazilian population.

BACKGROUND: Metallothioneins (MTs) gene polymorphisms have been associated with the ability of free radical scavenging and detoxification of heavy metals leading to cancer development. Our aim was to revisit, in a Brazilian population, single-nucleotide polymorphisms (SNPs) of the MT gene family previously associated with oral squamous cell carcinoma (OSCC). MATERIAL AND METHODS: A case-control investigation with 28 OSCC patients and 45 controls was conducted, using conventional risk factors (tobacco use and alcohol consumption) as covariates. SNPs genotyping for rs8052334 (MT1B), rs964372 (MT1B), and rs1610216 (MT2A) was performed by PCR-RFLP, and SNPs for rs11076161 (MT1A) were analyzed by TaqMan assay. RESULTS: The only SNP associated with increased risk for OSCC was the MT-1A AA genotype (OR = 4.7; p = 0.01). We have also evidenced for the first time a significant linkage disequilibrium between the SNPs of MT-2A and MT-1A in this population with the highest frequency (30%) of the unfavorable haplotype G/A/C/T (rs1610216 / rs11076161 / rs964372 / rs8052334) of MT gene polymorphisms (OR = 6.2; p = 0.04). Interestingly, after removing the effects of conventional risk factors, we have uncovered the significance of the AA genotype of the rs11076161 with increased odds of 19-fold higher towards OSCC development. CONCLUSIONS: This is the first demonstration that a significant linkage disequilibrium among gene polymorphisms of the MT family may affect susceptibility to oral cancer, which is conditioned by the G/A/C/T haplotype (rs1610216/rs11076161/rs964372/ rs8052334) and the MT-1A gene polymorphism has a potential clinical utility for the OSCC risk assessment.

Simple bone cyst: description of 60 cases seen at a Brazilian School of Dentistry and review of international literature.

BACKGROUND: The aim of this study was to describe the relative frequency and the main demographic and clinic-radiographic features related to patients diagnosed with Simple bone cyst (SBC) in an Oral Diagnosis Service in Southeast Brazil and present a review and discussion of international literature on this topic. MATERIAL AND METHODS: SBC cases from our service encompassing the period between 1978 and 2017 were selected. In addition, a literature search was performed in the Pubmed/MEDLINE online electronic database published between 1951 and 2019. RESULTS: A total of 2,459 cystic lesions were documented in our service, thus 60 patients were diagnosed with the SBC representing 2.4% of all jaw cystic. Most of cases were asymptomatic. Multiple SBC lesions were seen in two patients (3.4%) and association with cemento-osseous dysplasia was seen in one female patient (1.7%). A total of 793 cases were enrolled in this literature review. CONCLUSIONS: The SBC is an asymptomatic lesion often discovered in routine image exams in young patients. The unilocular, well defined margin with scalloped appearance is characteristic and helps the definition of diagnosis. This review suggests a different epidemiologic trend concerning to the sex and it confirms the posterior region of mandible as the more frequent location. The conservative treatment with limited exploration and curettage remains as the gold-standard treatment.

Differential metallothionein expression in oral lichen planus and amalgam-associated oral lichenoid lesions.

BACKGROUND: Oral lichen planus (OLP) is a chronic inflammatory disease mediated by T cells, which manifests as reticular (white) or erosive (red) lesions, that are eventually painful. Oral lichenoid lesion (OLL) are distinguished from OLP by the presence of precipitating factors. The aim of this study was to evaluate whether the presence of metallothionein, which is involved in anti-apoptotic pathways and the anti-oxidative response, could serve as a differential diagnostic for OLP and OLL. MATERIAL AND METHODS: We evaluated the expression of metallothionein in 40 cases of OLP and 20 cases of OLL using immunohistochemistry. RESULTS AND CONCLUSIONS: White OLP has higher concentrations of metallothionein than red OLP in basal and parabasal layers. Moreover, metallothionein was more frequently observed in the cytoplasm and nuclei of basal cells in OLP patients compared to the same regions of OLL cases. Metallothionein levels are related to OLP severity and may contribute to a differential diagnosis between OLP and OLL.

A rare case of sclerosing mucoepidermoid carcinoma arising in minor salivary glands with immunohistochemical evaluation.

Mucoepidermoid carcinomas (MECs) are the most common malignancy of the salivary glands demonstrating a wide range of histologic variants and behavior. However, the sclerosing mucoepidermoid carcinoma (SMEC), a morphologic variant of this tumor is extremely rare and has been described almost exclusively in the major glands. The prominent sclerosis observed may obscure its typical morphological feature resulting in a diagnostic challenge. We describe herein a case of SMEC in a 43-year-old-woman, occurring in the minor salivary glands of palate. To our knowledge only 13 cases have been reported until this moment, being only 2 in minor salivary glands. We also performed the immunohistochemical evaluation of c-erbB-2 and Ki-67, searching for an association with the histopathological findings and behavior.

Oral phaeohyphomycosis.

This is the first description of solitary phaeohyphomycosis affecting the mucosal surface. The lesion developed in the inferior lip of a 57-year-old woman. After surgical resection, histopathological examination evidenced characteristic brownish fungal structures within granulomatous-purulent inflammation. Amplification and sequencing of rDNA obtained from paraffin-embedded tissue identified Alternaria species, as the causative agent.

Adenoid cystic carcinoma of the maxillary sinus: a clinical-pathological report of 10 years of experience from a single institution.

Adenoid cystic carcinoma (ACC) is the most common malignant salivary gland tumour of the maxillary sinus. The present study describes 24 cases seen over a period of 10 years at the Brazilian National Cancer Institute. Socio-demographic, clinical, pathological, and follow-up data were retrieved from the medical files for the period 1997-2006. The mean age of the patients was 51.1 years. Twenty-one (87.5%) presented advanced tumours. The main signs and symptoms found were a tumour mass (87.5%), pain (50%), nasal obstruction (25%), and epistaxis (20.8%). Most cases (62.5%) were treated with surgery and radiation therapy. Follow-up data showed two patients (8.3%) with residual disease, local recurrences in four (16.7%) patients, and distant metastasis in five (20.8%). The overall 5- and 10-year survival rates were 72.61% and 62.11%, respectively. Maxillary sinus ACC has an aggressive but indolent behaviour, typically presenting at an advanced T stage that reflects a poor prognosis for patients.

Small cell carcinoma of the salivary gland: a systematic literature review and two case reports.

Salivary gland small cell carcinoma is a rare neoplasm, accounting for less than 1% of salivary gland tumours. Little is known about the epidemiologic factors and treatment of this lesion. The authors report two cases and perform a systematic literature search from 1960 to 2011 for articles on salivary gland small cell carcinoma. Once the papers were reviewed, a database was generated to analyse clinical and pathological features, treatments and outcomes, and an attempt was made to identify prognostic factors. Available data were retrieved for 44 cases which fully satisfied the inclusion criteria; the median age was 64.25 years and the male:female ratio was 2.4:1. The parotid gland was the most common site (79.6%). The overall 1-, 2- and 5-year survival rates were 75.3%, 56.4% and 36.6%, respectively. According to the present review, patient age, tumour size, distant metastasis and cytokeratin-20 positive immunostaining were all significant prognostic factors in a univariate analysis. No particular treatment approach appeared to improve survival. This work reinforces knowledge about salivary gland small cell carcinoma's epidemiologic features, and identifies new prognostic markers. The optimal management of this lesion remains controversial.

Odontogenic tumours: 240 cases diagnosed over 31 years at a Brazilian university and a review of international literature.

This study describes the epidemiology and clinical presentation of odontogenic tumours (OT) seen at a regional Brazilian oral and maxillofacial pathology service; to assess the quantitative impact of the most recent World Health Organization (WHO) classification of these lesions; and to compare this series with others available in international databases. The study was carried out by retrospectively analysing 240 cases diagnosed from 1978 to 2009, followed by a comprehensive review of the literature. The patients' mean age was 29 years, with a male to female ratio of 1:1.1. Benign lesions comprised 97.9% of the cases (mostly keratocystic odontogenic tumours (KCOT), odontomas and ameloblastomas) with the remaining tumours depicting a prevalence of less than 5%. Adenomatoid OT were less frequent than in most previous studies, while malignant OT were strikingly numerous. Most OT in children and in the anterior maxilla were odontomas, while maxillary ameloblastomas were rare. Lack of swelling was more frequent in KCOT than in ameloblastomas. The present study confirms the relative impact of KCOT in the epidemiology of OT and identifies more similarities between the present series with reports from the United States and Europe than with African and Asian populations.

Metastatic tumours to the head and neck: retrospective analysis from a Brazilian tertiary referral centre.

Data regarding the development of head and neck metastases are limited, with the majority of the studies focusing on single cases affecting mainly the oral cavity and surrounding tissues. This study describes the incidence of head and neck metastases from primary tumours originating elsewhere. The medical records of selected patients were reviewed, and socio-demographic data as well as information about the localization of the primary tumours and their metastases to this region, treatment modalities employed, follow-up, and outcomes were collected. A total of 24 cases were found. The mean age at diagnosis was 52.1±17.6 years and the male to female ratio was 1:1.4. Most primary tumours were located in the lung and breast. The overall 1-, 2-, and 5-year survival rates were 63.0%, 39.1%, and 19.6%, respectively. Radiotherapy for the metastatic focus significantly prolonged the survival time of the patients (P=0.048). Cervical lymph node metastases are a common event in patients with primary tumours growing elsewhere.

Odontogenic tumours in children and adolescents: a collaborative study of 431 cases.

This study describes the oral and maxillofacial pathological characteristics of a series of odontogenic tumours in children and adolescents from three Brazilian reference centres. The records were reviewed for all odontogenic tumours in patients up to 18 years old based on criteria proposed by the World Health Organization (WHO) in 2005. Data concerning sex, age, skin colour and tumour location were collected and plotted. Four hundred and thirty one odontogenic tumours in children and adolescents were found, accounting for 37.5% of the total number of odontogenic tumours diagnosed. Benign tumours were predominant (99.8% of the cases), and odontoma was the most frequent type (41.4%), followed by keratocystic odontogenic tumours (25.5%) and ameloblastoma (14.6%). Odontogenic tumours were rarely detected in early childhood, and their prevalence increased with age. An almost equal distribution was observed with respect to sex and the site of the lesions. This study is the largest reported retrospective analysis describing odontogenic tumours in children and adolescents to date. The authors detected some variation in the relative frequency of odontogenic tumours compared with similar reports. Additional studies should be conducted based on the new WHO classification and predetermined age parameters to enable comparative analysis among different worldwide populations.

Scintigraphy in postoperative follow-up of osteosynthesis of the femur with a bridge plate associated with an intramedullary pin in rabbits / Cintilografia no acompanhamento pós-operatório de osteossíntese do fêmur com placa em ponte associada ao pino intramedular em coelhos

The objective of this work was to monitor the consolidation of the femur after osteosynthesis with a bridge plate associated with the intramedullary pin using scintigraphy. We used seven New Zealand breed male rabbits, at 4 months of age, with a mean weight of 3.5 kg. We performed a three-phase bone scintigraphy with technetium-labeled methylene diphosphonate (99mTc-MDP) before and after surgery, and 20, 50 and 90 days postoperatively. The activity index (AI) was calculated by dividing the average number of uptake counts in the region of the osteotomy by the average number of counts in the corresponding region in the contralateral limb. Radiography was performed before surgery, after surgery, and 15, 30, 45, 60 and 90 days postoperatively. We found a direct relationship between the activity index and progress of bone scintigraphy in the evaluation sequence over the period of observation. Scintigraphy allows monitoring of bone metabolism and measurement of vascularization and/or bone or tissue perfusion. The images obtained in the blood pool and static phases are the most appropriate for assessing bone metabolism in the context of this study. The bridge plate associated with the intramedullary pin promotes osteosynthesis with sufficient stability to allow bone consolidation.

A cintilografia foi empregada no acompanhamento da consolidação de osteotomia experimental do fêmur após osteossíntese com placa em ponte associada ao pino intramedular. Foram usados sete coelhos machos, raça Nova Zelândia, com massa corporal de 3,5kg e idade média de quatro meses. A cintilografia óssea trifásica com metilenodifosfonato marcado com tecnécio-99m (MDP-99mTc) foi obtida antes e após a cirurgia, e nos dias 20, 50 e 90 do pós-operatório.O índice de atividade (IA) foi calculado por meio do quociente da média do número de contagens na região da osteotomia pela média do número de contagens na região correspondente, no membro contralateral normal. Paralelamente ao estudo cintilográfico, foram realizadas radiografias antes dos procedimentos cirúrgicos e aos 15, 30, 45, 60 e 90 dias após, para acompanhamento do processo de cura óssea. Encontrou-se relação direta entre o índice de atividade e a evolução do processo de consolidação óssea na avaliação cintilográfica sequencial ao longo do período de observação. A cintilografia óssea trifásica permite acompanhar o metabolismo ósseo, avaliar e mensurar a vascularização e perfusão tecidual. As imagens obtidas na fase de pool sanguíneo e na fase óssea são as mais adequadas para avaliação do metabolismo ósseo. A placa em ponte associada com o pino intramedular promove osteossíntese com estabilidade suficiente para permitir a consolidação ossea.

Effectiveness of computed tomography to evaluate central giant cell lesion.

Central giant cell lesion (CGCL) is a benign disease involving the mandible (70%) more than the maxilla; it tends to be more common in women. Clinically, the lesion may be associated with pain, tooth displacement, facial asymmetry, paraesthesia and ulceration of the mucosa. The radiographic aspect of CGCL is highly variable since it may appear as a unilocular or multilocular radiolucent area with expansion and perforation of the cortical bone. Few previous reports have dealt with the usefulness of CT in the evaluation of this lesion. The purpose of this study is to report the clinical and imaging features of a case, including CT, treated by a conservative method.

Apoptosis in epithelial cells of apical radicular cysts.

AIM: To investigate the occurrence of apoptotic cell death in the epithelium of radicular cysts and to compare its frequency in lesions presenting a distinct functional state. METHODOLOGY: Twenty radicular cysts were selected and arranged into two groups with 10 lesions in each group: atrophic (quiescent) and hyperplastic (active) epithelium. Morphologic investigations of apoptosis were conducted by means of optic microscopy in haematoxylin and eosin slides. Immunohistochemical techniques to detect the bcl-2 protein were carried out by streptavidin-biotin-peroxidase assay. In both instances, 30 sequential high-power microscopic fields were observed to determine apoptotic (AI) and bcl-2 immunostaining (bcl-2I) indexes. The presence of AI and bcl-2I within the two groups was compared using the t-test. Correlation between the AI and the bcl-2I was investigated using the Spearman test. RESULTS: Apoptosis was detected in the epithelium of all cysts. Higher AI levels were found in lesions with an atrophic (0.17 +/- 0.19) rather than a hyperplastic (0.10 +/- 0.10) epithelium. The same was found for the bcl-2I levels (0.06 +/- 0.03 vs. 0.04 +/- 0.01, respectively). However, these differences were not statistically significant. A positive and significant correlation was found between AI and bcl-2I. CONCLUSIONS: Apoptosis was always present in the epithelium of the lesions and was more frequent in lesions with atrophic (quiescent) epithelium.

Mucus extravasation phenomenon in newborn babies: report of two cases.

Two rare cases of congenital mucoceles in newborn babies are reported. The patients presented with nodular swellings on their lower lips at birth with no obvious local aetiology. In both cases the mucoceles interfered with normal feeding. The lesions were excised by surgical approach under general anaesthesia and histopathological examination confirmed the lesions to be extravasation-type mucoceles. The article includes a brief discussion of the epidemiology and ethiopathogeny of mucoceles.

Exfoliative cytology: a helpful tool for the diagnosis of paracoccidioidomycosis.

OBJECTIVE: To describe the main cytological findings associated with smears collected from oral lesions of paracoccidioidomycosis and to appraise the use of cytology as a diagnostic tool for the disease. STUDY DESIGN: Cytological smears and biopsies were collected from 40 lesions with a clinical suspicion of paracoccidioidomycosis. Evaluation of the sensitivity, specificity, positive and negative predictive values, accuracy and the positive likeness ratio of the oral smear when compared with the histological diagnosis, was performed. The latter is considered the 'gold standard' for comparison. RESULTS: The main morphological findings were the rounded-shaped, birefringent and multiple-budded fungi, Langhans' giant cells and epithelioid cells. The following associative measures were found: sensitivity, 67.9%; specificity, 91.7%; positive predictive value, 95.0%; negative predictive value, 55.0%; accuracy, 75.0%; and positive likeness ratio, 8.14. CONCLUSION: The cytological findings of paracoccidioidomycosis are characteristic and cytology is accurate in the diagnosis of the disease. Positive patients should be treated. Negative patients should be submitted to biopsy to confirm or to dismiss the diagnosis of this mycosis.