Contribution of public oral pathology services to the diagnosis of oral and oropharyngeal cancer in Brazil.

This study aimed to evaluate the contribution of oral and maxillofacial pathology laboratories (OMPLs) in Brazilian public universities to the diagnosis of lip, oral cavity, and oropharyngeal squamous cell carcinoma (SCC). A cross-sectional study was performed using biopsy records from a consortium of sixteen public OMPLs from all regions of Brazil (North, Northeast, Central-West, Southeast, and South). Clinical and demographic data of patients diagnosed with lip, oral cavity, and oropharyngeal SCC between 2010 and 2019 were collected from the patients' histopathological records.

Hamartomatous Polyp of the Palatine Tonsil: A Case Report and Critical Literature Review.

Background: Hamartomatous polyp of the palatine tonsil is a rare benign tumor poorly recognized by clinicians and pathologists. We present a novel case report and provide a literature review about this diagnosis, highlighting its clinicopathological features and treatment modalities.

Methods: We herein report a case of a 22-year-old female patient who complained of a foreign body sensation in her throat.

The Role of Immunohistochemistry for Primary Oral Diagnosis in a Brazilian Oral Pathology Service.

A proper antibody panel selection is one of the most important factors to reach an adequate diagnosis in challenging cases. This retrospective study was designed to determine the contribution of immunohistochemistry (IHC) in the primary diagnosis of oral diseases in one of the main services of oral pathology in the State of São Paulo, Brazil, and to identify the most common antibodies used, and recommend diagnostic algorithms based on our experience with challenging lesions. A total of 1698 IHC stains were performed in 401 cases from a total of 28,804 cases received from public dental clinics and private dental practitioners within a period of 13 years, representing a frequency of 1.

DNA methylation status of MutS genes in ameloblastoma.

Objectives: Ameloblastoma is an odontogenic epithelial tumour with a low expression of mismatch repair system components. We aimed to investigate the methylation status of the genes MSH2, MSH3 and MSH6 (MutS group) in conventional ameloblastomas.

Materials And Methods: The ameloblastoma and dental follicle samples (n = 10 each) were collected from 20 different patients.

Immunohistochemical Expression of Fatty Acid Synthase (FASN) is Correlated to Tumor Aggressiveness and Cellular Differentiation in Salivary Gland Carcinomas.

Fatty acid synthase (FASN) expression is closely related to cancer progression, in particular, tumor aggressiveness and poor prognosis. This study aimed to analyse the expression of FASN in carcinomas of the salivary glands and correlate it with Ki-67 expression. We analysed by immunohistochemistry the expression of FASN and Ki-67 on tissue sections from 7 cases of adenocarcinoma, not otherwise specified (AdNOS), 6 cases of polymorphous adenocarcinoma (PAC), 16 cases of acinic cell carcinoma (AcCC), 19 cases of adenoid cystic carcinoma (AdCC), 15 cases of epithelial-myoepithelial carcinoma (EMC); 10 cases of secretory carcinoma (SC), 13 cases of mucoepidermoid carcinoma (MEC), 10 cases of salivary duct carcinoma (SDC) and 7 cases of myoepithelial carcinoma (MC).

Fully digital pathology laboratory routine and remote reporting of oral and maxillofacial diagnosis during the COVID-19 pandemic: a validation study.

The role of digital pathology in remote reporting has seen an increase during the COVID-19 pandemic. Recently, recommendations had been made regarding the urgent need of reorganizing head and neck cancer diagnostic services to provide a safe work environment for the staff. A total of 162 glass slides from 109 patients over a period of 5 weeks were included in this validation and were assessed by all pathologists in both analyses (digital and conventional) to allow intraobserver comparison.

Oral and oropharyngeal diffuse large B-cell lymphoma and high-grade B-cell lymphoma: A clinicopathologic and prognostic study of 69 cases.

Objective: The objective of this study was to describe the clinicopathological, molecular, and prognostic features of oral/oropharyngeal diffuse large B-cell lymphoma (DLBCL) and high-grade B-cell lymphoma.

Study Design: All cases were retrieved from 7 Brazilian institutions. Immunohistochemical reactions were performed to confirm the diagnoses and to categorize the tumors.

An audit of cytopathology in the oral and maxillofacial region: 18 years of experience.

Introduction: The aim of this study was to perform an audit of oral and maxillofacial specimens submitted for cytological diagnosis to verify the importance of this complementary examination.

Methods: A retrospective analysis of our institutional cytopathology database was performed over an 18-year period. Clinical information and cytological data were collected.

β-catenin and Its Relation to Alveolar Bone Mechanical Deformation - A Study Conducted in Rats With Tooth Extraction.

The aim of this study was to analyze the relationship between alveolar bone deformation and β-catenin expression levels in response to the mechanical load changed by dental extraction in adult rats. Twenty-four male rats (), Wistar linage, at 2 months of age, were used. The right upper incisor tooth was extracted, and euthanasia occurred in periods 5 ( = 6), 7 ( = 6), and 14 ( = 6) days after Day 0.

A Brazilian multicentre study of 2,497 isolated cases of odontogenic keratocysts.

We present the frequency of cases of isolated odontogenic keratocysts submitted to microscopic examination at 10 Brazilian referral centres in Oral and Maxillofacial Pathology. In a retrospective (1953-2017) analysis, data on clinicoradiographic features and treatment of these lesions were collected and analysed descriptively. Among the 258,867 cases retrieved, 2,497 (0.

Activation of BDNF/TrkB/Akt pathway is associated with aggressiveness and unfavorable survival in oral squamous cell carcinoma.

Objectives: To evaluate the expression of brain-derived neurotrophic factor (BDNF), its tyrosine kinase receptor B (TrkB), and two downstream targets of this pathway, Akt and ribosomal protein S6 (RPS6), in normal oral mucosa (NOM), oral leukoplakia (OL), and oral squamous cell carcinoma (OSCC) and correlate this expression with OSCC patients' outcomes, cell senescence, and "stemness" profile.

Materials And Methods: Ten cases of NOM, 32 OL, and 72 primary OSCC were included. Immunohistochemical analysis for BDNF, TrkB, p-TrkB, p-Akt, and p-RPS6 was performed.

COX-2 as a determinant of lower disease-free survival for patients affected by ameloblastoma.

Ameloblastoma is a locally aggressive neoplasm with a poorly understood pathogenesis. Therefore, the aim of this study is to investigate whether COX-2 expression is associated with ameloblastoma microvascular density (MVD) and with tumor aggressiveness. Sixty-three cases of primary ameloblastomas arranged in tissue microarray were submitted to immunohistochemistry against cyclooxigenase-2 (COX-2) and CD34.

Prognostic importance of FGF2 and FGFR1 expression for patients affected by ameloblastoma.

Background: Fibroblast growth factor 2 (FGF2) and FGF receptor 1 (FGFR1) have been investigated in different human neoplasms and were shown to play important roles in the pathogenesis of these diseases; however, very few are known regarding their prognostic importance in the context of ameloblastoma. Therefore, the aim of this study was to investigate whether the expression of FGF2 and FGFR1 is associated with ameloblastoma clinical behavior.

Methods: Fifty-eight cases of ameloblastoma arranged in tissue microarray were submitted to immunohistochemistry against FGF2 and FGFR1.

Odontogenic keratocyst: The role of the orthodontist in the diagnosis of initial lesions.

Odontogenic keratocysts (OKCs) are locally infiltrative odontogenic cysts that are usually diagnosed during routine radiographic examinations. Therefore, it is critical that dental practitioners, in particular orthodontists, recognize and diagnose OKCs to recommend appropriate treatment. This report describes a patient whose OKC was not initially identified during orthodontic pretreatment.

Prognostic significance of hMSH2, hMSH3, and hMSH6 expression in ameloblastoma.

Objective: The aim of this study was to investigate hMutS proteins in developing human tooth, ameloblastomas, and ameloblastic carcinoma and to determine whether the expression of these proteins has any prognostic potential.

Study Design: Ten cases of developing human tooth, 39 ameloblastomas, and 2 ameloblastic carcinomas were used to determine the distribution of the proteins during the process of carcinogenesis. Simultaneously, another sample of 73 ameloblastomas was arranged in tissue microarray, and their clinical, microscopic, and radiographic features; treatment outcome; presence of BRAF-V600E mutation; and follow-up data were assessed to determine the prognostic relevance of the expression of hMutS (hMSH2, hMSH3, hMSH6) and Ki-67.

Mismatch repair system proteins in oral benign and malignant lesions.

Different environmental agents may cause DNA mutations by disrupting its double-strand structure; however, even normal DNA polymerase function may synthesize mismatch nucleotide bases, occasionally demonstrating failure in its proofreading activity. To overcome this issue, mismatch repair (MMR) system, a group of proteins specialized in finding mispairing bases and small loops of insertion or deletion, works to avoid the occurrence of mutations that could ultimately lead to innumerous human diseases. In the last decades, the role of MMR proteins in oral carcinogenesis and in the development of other oral cavity neoplasms has grown, but their importance in the pathogenesis and their prognostic potential for patients affected by oral malignancies, especially oral squamous cell carcinoma (OSCC), remain unclear.