Assessing the oral microbiome of head and neck cancer patients before and during radiotherapy.

Objective: To characterize the oral microbiome of patients with head and neck squamous cell carcinoma (HNSCC) before and during radiotherapy (RT), compared to healthy individuals. Evaluating the impact of oral microbiome in the clinical outcomes one year following the end of RT.

Methods: Oral samples were collected from HNSCC patients who underwent RT using the following regimens: no dose received (T0), dose 12-16 Gy (T1), dose 30-36 Gy (T2) and dose ≥ 60 Gy (T3).

Morphological features and genetic background in ectomesenchymal chondromyxoid tumor: A systematic review.

Background: Ectomesenchymal chondromyxoid tumor (EMCMT) is a rare neoplasm that mainly affects the tongue and harbors recurrent, although not exclusive, gene fusions. Owing to its rarity, overlapping features with other tumors may lead to challenges in the microscopic diagnosis. We aimed to perform a systematic review focusing on the histomolecular findings of EMCMT of the oral and maxillofacial region and to evaluate the possible association between microscopic features with the genetic background.

Subgemmal neurogenous plaque: a series of six cases and a literature overview.

The study aims to describe six subgemmal neurogenous plaque (SNP) cases and compile the previously available data on SNP. Searches on PubMed, Web of Science, Embase, Scopus, and a two-step study selection were performed to compile data from case reports/series of SNP published in English literature. Our six patients (range 29-63 years) had SNP in the posterior lateral border of the tongue.

Can SARS-CoV-2 screening in oral biopsies aid epidemiological surveillance?

Background: Three years after the first confirmed COVID-19 case in Brazil, the outcomes of Federal government omissions in managing the crisis and anti-science stance heading into the pandemic have become even more evident. With over 36 million confirmed cases and nearly 700 000 deaths up to January 2023, the country is one of the hardest-hit places in the world. The lack of mass-testing programs was a critical broken pillar responsible for the quick and uncontrolled SARS-CoV-2 spread throughout the Brazilian population.

Clinical diagnostic approach for oral lymphomas: a multi-institutional, observational study based on 107 cases.

Objective: To evaluate oral lymphomas' clinical manifestations and investigate whether clinical features are associated with lymphoma subtypes.

Study Design: Oral lymphomas with at least 1 representative clinical image were evaluated. They were classified according to their microscopic grade (high vs low), predominant cell size (small vs medium/large), and cellular lineage (B cell vs T cell).

Fine-needle aspiration cytology for the diagnosis of plasma cell neoplasms in the head and neck region: A systematic analysis of the literature.

Background: Cytopathologic analysis is feasible and provides detailed morphological characterisation of head and neck lesions.

Aims: To integrate the available data published on fine-needle aspiration cytology (FNAC) used for the diagnosis of plasma cell neoplasms (PCN) of the head and neck region.

Materials And Methods: Searches on PubMed, Web of Science, Embase, and Scopus were performed to compile data from case reports/case series published in English.

Interrogation of TERT promoter hotspot mutations in ameloblastoma and ameloblastic carcinoma.

Background: TERT promoter mutations increase telomerase activity, conferring cell immortality. The coexistence of TERT promoter mutations with BRAFV600E is associated with aggressiveness. Ameloblastoma and ameloblastic carcinoma are infiltrative neoplasms that harbor BRAFV600E; however, it remains unknown if these odontogenic tumors also show TERT promoter mutations.

Oral Juvenile Xanthogranuloma: A Clinicopathological, Immunohistochemical and BRAF V600E Study of Five New Cases, with Literature Review.

Juvenile xanthogranuloma (JXG) is the most common form of non-Langerhans cell histiocytosis and oral mucosal involvement is exceedingly rare. Histiocytic disorders harbor activating mutations in MAPK pathway, including the report of BRAF V600E in JXG of extracutaneous site. However, no information is available for oral JXG.

Fat-free pleomorphic lipoma of the buccal mucosa: An immunohistochemical study and literature review.

Pleomorphic lipomas are extremely rare in the oral cavity. Due to the significant overlap of morphological findings with several benign and malignant soft tissue tumors, especially in the absence of adipocytes, the diagnosis is challenging. We reported the clinicopathological and immunohistochemical features of an uncommon case of a fat-free variant of pleomorphic lipoma in a 48-year-old female presenting clinically as a painless nodule on the buccal mucosa.

Whole-exome sequencing reveals novel vacuolar ATPase genes' variants and variants in genes involved in lysosomal biology and autophagosomal formation in oral granular cell tumors.

Background: Granular cell tumors (GCTs) are rare neuroectodermal soft tissue neoplasms that mainly affect the skin of the upper limbs and trunks and the oral cavity. GCTs are derived from Schwann cells and, ultrastructurally, their intracytoplasmic granules are considered autophagosomes or autophagolysosomes and are consistent with myelin accumulation.

Methods: In this study, a convenience set of 22 formalin-fixed, paraffin-embedded samples of oral GCTs, all but one sample located at the tongue, was screened for mutations by whole-exome (WES) or targeted sequencing.

Sialolipomas of minor salivary glands: A multi-institutional study and literature review.

Background: Sialolipoma is a rare histological variant of lipoma commonly misdiagnosed and composed of a proliferation of mature adipocytes with secondary entrapment of normal salivary gland tissue. The purpose of the present study is to report the clinicopathologic and immunohistochemical features of 10 new cases of sialolipomas in conjunction with a review of the literature.

Methods: A retrospective descriptive cross-sectional study was performed.

Genotoxic and cytotoxic effects of mobile phone use on the oral epithelium: a systematic review with meta-analysis.

The use of mobile phones is based on radiofrequency (RF) waves, and the devices act as transmitters and receivers of non-ionizing energy. The micronucleus test was developed to identify increases in the occurrence of mutations in cells exposed to various agents. This systematic review with meta-analysis adhered to the following protocol: defining the objective, outlining the search method (PICO model), conducting the search, identifying literature, selecting articles, and extracting data.

Targeted Next-Generation Sequencing and Allele-Specific Quantitative PCR of Laser Capture Microdissected Samples Uncover Molecular Differences in Mixed Odontogenic Tumors.

The molecular pathogenesis of mixed odontogenic tumors has not been established, and understanding their genetic basis could refine their classification and help define molecular markers for diagnostic purposes. Potentially pathogenic mutations in the component tissues of 28 cases of mixed odontogenic tumors were assessed. Laser capture microdissected tissue from 10 ameloblastic fibromas (AF), 4 ameloblastic fibrodentinomas (AFD), 6 ameloblastic fibro-odontomas (AFO), 3 ameloblastic fibrosarcomas (AFS), and 5 odontomas (OD) were screened by next-generation sequencing and results confirmed by TaqMan allele-specific quantitative PCR.

Aggressive Intraosseous Myofibroma of the Maxilla: Report of a Rare Case and Literature Review.

Myofibroma (MF) is a benign mesenchymal myofibroblast-derived tumor, which occurs most frequently in children, and rarely affects the maxilla. We reported a case of an aggressive intraosseous lesion found in the maxilla of a 9-year-old female child. Intraorally, the swelling extended from tooth 12 to 16, causing displacement of teeth 13, 14, and 15.

Odontogenic myxomas lack PDGFRB mutations reported in myofibromas.

Background: The molecular pathogenesis of odontogenic myxoma has not been established yet. Considering that odontogenic myxoma may show myofibroblastic differentiation and myxoid areas can be observed in intra-osseous myofibromas, we tested the hypothesis whether both tumors share a common molecular profile. As recent studies have reported PDGFRB recurrent driver mutations in myofibroma, we evaluated PDGFRB mutations in odontogenic myxomas.

CTNNB1 and APC mutations in odontogenic carcinoma with dentinoid.

The purpose of the present study is to report 2 cases of odontogenic carcinoma with dentinoid, a rare low-grade odontogenic carcinoma associated with facial deformity and bone loss, and to investigate the presence of pathogenic mutations in these samples. By using a next-generation sequencing approach, we sequenced a panel of 50 oncogenes and tumor suppressor genes commonly mutated in human cancer. Microscopic features of both cases revealed solid areas of malignant odontogenic tumor with a large amount of dentinoid material.

Assessing pathogenic mutations in dental follicles as an attempt to identify early events in odontogenic tumours tumourigenesis.

Objective: Driver oncogenic mutations have been reported in several benign neoplasms. While ameloblastomas show BRAF p.V600E mutations, adenomatoid odontogenic tumours harbour either KRAS p.

Solitary fibrous tumour of the oral cavity: An update.

Background: Solitary fibrous tumour is an unusual neoplasm of the oral cavity that is sometimes not clinically distinguishable from other lesions. The purpose of the present study was to review the clinical, microscopic and molecular aspects of malignant and benign solitary fibrous tumour of the oral cavity currently available in literature.

Methods: For our review, an electronic search was performed using PubMed, Scopus, Ovid/MedLine, Web of science and ProQuest Dissertations and Theses Global database.

Plasma cell cheilitis: the diagnosis of a disorder mimicking lip cancer.

Plasma cell cheilitis (PCC) is an inflammatory disorder of unknown etiology that affects the lip. It is characterized histologically by a dense infiltrate of plasma cells with a variety of clinical features. The response to different therapeutic modalities is controversial, especially regarding the effectiveness of corticosteroids.

KRAS mutations drive adenomatoid odontogenic tumor and are independent of clinicopathological features.

Adenomatoid odontogenic tumor is a benign encapsulated epithelial odontogenic tumor that shows an indolent clinical behavior. We have reported in a few adenomatoid odontogenic tumors mutations in KRAS, which is a proto-oncogene frequently mutated in cancer such as lung, pancreas, and colorectal adenocarcinomas. We aimed to assess KRAS mutations in the hotspot codons 12, 13, and 61 in a large cohort of adenomatoid odontogenic tumors and to test the association of these mutations with clinical (age, site, tumor size, follicular/extrafollicular subtypes) and histopathological parameters.

Craniopharyngiomas and odontogenic tumors mimic normal odontogenesis and share genetic mutations, histopathologic features, and molecular pathways activation.

Odontogenic tumors bear some histopathologic and molecular resemblance to craniopharyngiomas. Specifically, adamantinomatous craniopharyngioma shares morphologic features and CTNNB1 (the gene encoding β-catenin) mutations with calcifying odontogenic cyst, whereas papillary craniopharyngioma and ameloblastoma are driven by BRAF mutations. Recently, important similarities between adamantinomatous craniopharyngioma and the cell signaling pathways involved in tooth formation have been described.