Objective The objective of this systematic review with meta‐analysis was to critically evaluate the available data on sensitivity and specificity of IHC compared with molecular tests in the detection of BRAF V600E mutation in ameloblastomas. Materials and methods This systematic review was performed based on the PRISMA statement and registered in Prospero (CRD42021259117). PubMed, Web of Science, Scopus, and Cochrane Library databases were searched for observational studies to answer the question “What is the diagnostic accuracy of immunohistochemistry compared with molecular tests for the diagnosis of BRAF V600E mutation in ameloblastomas?”. Methodological quality and risk of bias assessment of the selected studies were based on the QUADAS‐2. Meta‐analysis based on hierarchical SROC curve model and summary measures for sensitivity and specificity were computed. Results A total of 226 records were found, but only 05 articles met the inclusion criteria, with 277 FFPE specimens of ameloblastoma included in the quantitative analysis. The sensitivity of the IHC compared to molecular tests ranged from 0.71 to 1.00, while all of the included studies showed perfect specificity (1.00). Pooled measures for sensitivity and specificity were 0.95 [95% CI 0.89, 1.00] and 1.00 [95% CI 0.95, 1.00], respectively. The diagnostic odds ratio was 4.05, and the AUC for SROC curve was calculated as 0.979. Conclusions BRAF V600E‐specific IHC using VE1 antibody showed extremely high sensitivity and specificity when compared with molecular tests in the detection of the mutation in ameloblastomas.

Background: Burkitt lymphoma (BL) is an aggressive B-cell lymphoma with three variants (endemic, sporadic, and immunodeficiency-associated), presenting with specific epidemiological and clinical features. Burkitt lymphoma affects the head and neck region (BLHN) in approximately 10% of cases. The aim of this study was to undertake a comparative analysis of the clinicopathologic and immunohistochemical (IHC) features of BLHN diagnosed in patients from Africa, Guatemala, and Brazil. Methods: Cases diagnosed as BLHN were collected from the files of six oral pathology laboratory services (Brazil, South Africa, and Guatemala) and one Brazilian pediatric oncology hospital from 1986 to 2020. Clinicopathological and IHC data, and Epstein-Barr virus (EBV) status by in situ hybridization data for each case were reviewed and described. Results: Of the 52 cases, BLHN was predominant in pediatric patients [43 (82.69%)] and males [43 (82.69%)], with a mean age of 11.26 ± 9.68 years (range, 1-39 years). Neck and cervical lymph nodes [14 (26.92%)], and involvement of both maxilla and mandible [8 (15.38%)], were the most common anatomical sites. Clinically, tumor/ swelling [40 (31.25%)], cervical lymphadenopathy [14 (10.94%)], pain [12 (9.38%)], and bone destruction [12 (9.38%)] were frequent findings. All cases showed typical morphological characteristics of BL. IHC profiles included positivity for CD20 [52 (100%)], CD10 [38 (79.17%)], Bcl6 [29 (87.88%)], and c-Myc protein [18 (81.82%)]. EBV was positive in 18 cases (62.07%). The Ki-67 index ranged from 90 to 100%. Special issue "Lymphomas and lymphoid lesions of the oral cavity".| 573 ARBOLEDA Et AL.

Objective: This study aimed to evaluate the relative prevalence, demographic distribution and clinical-pathological characteristics of the maxillary odontogenics cysts and tumors of the jaws in a pathology laboratory located in a university hospital in Northeastern Brazil. Methods: An observational and retrospective study was carried out, in which information was collected on histopathological diagnosis, age, gender and location of the lesion of patients who had been diagnosed with odontogenic cysts or odontogenic tumors between 2013 and 2020.  Results: Among the 546 specimens, 57 were odontogenic cysts and 41 were odontogenic tumors. The most frequent odontogenic cysts were the odontogenic keratocyst 21 (21.4%) and the root cyst 19 (19.4%). The most frequent odontogenic tumors were ameloblastoma 27 (27.6%) and odontoma 6 (6.1%). Conclusion: The data found in this study are possibly associated with the service assistance profile.

Background Although there are no population-based studies that support an association, there are reports in the literature of mucocutaneous, vesiculobullous and ulcerated lesions in the oral mucosa in cases of arbovirus infection. The aim of this study is to analyze the prevalence of ulcerative stomatitis in individuals affected by arboviruses in a population of the municipality of Arcoverde, Pernambuco, Brazil. Material and Methods 1,003 people living in an area assigned to a Primary Health Care Unit were interviewed. A structured questionnaire was used for data collection, with questions about sociodemographic variables, residence conditions, general health information, as well as information about the general signs and symptoms of arboviruses and specifically about oral lesions. Results Of the 1,003 individuals interviewed, 815 (81.25%) were infected by one or more arboviruses. Of these, 147 (18%) reported ulcerated oral lesions during arbovirus infections. The association between arbovirus infections and the presence of ulcerated oral lesions was statistically significant ( p = 0.000). Conclusions In these cases, the ulcerated lesions on the oral mucosa appear to be associated with arbovirus infection, especially Chikungunya, although the pathophysiological mechanisms are not defined, and the studies are not sufficient to confirm this association. Key words: Arbovirus infections, Dengue, Chikungunya fever, Zika virus.