Oral squamous cell carcinoma arising from areas of Graft-versus-host disease: A systematic review / Carcinoma oral de células escamosas que surge de áreas de enfermedad de injerto contra huésped: una revisión sistemática

Background: Graft-versus-host disease (GVHD) is an immune system reaction that occurs in patients with ahistory of hematopoietic stem cell transplantation (HSCT), in which the grafted donor's cells attack those of thehost. The objective of this systematic review was to present a study on oral squamous cell carcinoma (OSSC) thatdeveloped from GVHD areas in patients undergoing HSCT.Material and Methods: An electronic search was conducted in the databases PUBMED, WEB OF SCIENCE,SCOPUS, MEDLINE and SCIENCE DIRECT, according to PRISMA guidelines. Results: Of the 1582 results, 23 articles were included, resulting in 81 cases. The most common underlying diseasefor performing the transplant was Myeloid Leukemia (55.6%). The mean age was 39 years, with a predilection formales (64.2%). The tongue was the site of GVHD that most frequently underwent transformation to SCC (59.3%).The average time between transplantation and the development of GVHD was of approximately of 8 months, whilethe average period of development between transplantation and the development of OSCC was of approximately of111 months. The most common treatment to GVHD was cyclosporine associated with corticosteroids.Conclusions: OSCCs arising from areas of GVHD present a different evolution from conventional oral carcinomas,since they affect younger patients, smoking and alcohol are not important etiological factors and finally because theypresent good prognosis, but further studies with larger number cases followed are needed to confirm our findings.(AU)

Oral manifestations of amyloidosis and the diagnostic applicability of oral tissue biopsy.

BACKGROUND: Amyloidosis exhibits a variable spectrum of systemic signs and oral manifestations that can be difficult to diagnose. This study aimed to characterize the clinical, demographic, and microscopic features of amyloidosis in the oral cavity. METHODS: This collaborative study involved three Brazilian oral pathology centers and described cases with a confirmed diagnosis of amyloidosis on available oral tissue biopsies. Clinical data were obtained from medical records. H&E, Congo-red, and immunohistochemically stained slides were analyzed. RESULTS: Twenty-six oral biopsies from 23 individuals (65.2% males; mean age: 59.6 years) were included. Oral involvement was the first sign of the disease in 67.0% of cases. Two patients had no clinical manifestation in the oral mucosa, although the histological analysis confirmed amyloid deposition. Amyloid deposits were distributed in perivascular (88.0%), periacinar and periductal (80.0%), perineurial (80.0%), endoneurial (33.3%), perimuscular (88.2%), intramuscular (94.1%), and subepithelial (35.3%) sites as well as around fat cells (100.0%). Mild/moderate inflammation was found in 65.4% of cases and 23.1% had giant cells. CONCLUSIONS: Amyloid deposits were consistently found in oral tissues, exhibiting distinct deposition patterns. Oral biopsy is less invasive than internal organ biopsy and enables the reliable identification of amyloid deposits even in the absence of oral manifestations. These findings corroborate the relevance of oral biopsy for the diagnosis of amyloidosis.

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. Of the 120,010 oral and maxillofacial biopsies (2010-2019), 6.9% (8,321 cases) were diagnosed as lip (0.8%, 951 cases), oral cavity (4.9%, 5,971 cases), and oropharyngeal (1.2%, 1,399 cases) SCCs. Most cases were from Brazil's Southeast (64.5%), where six of the OMPLs analyzed are located. The predominant profile of patients with lip and oral cavity SCC was Caucasian men, with a mean age over 60 years, low schooling level, and a previous history of heavy tobacco consumption. In the oropharyngeal group, the majority were non-Caucasian men, with a mean age under 60 years, had a low education level, and were former/current tobacco and alcohol users. According to data from the Brazilian National Cancer Institute, approximately 9.9% of the total lip, oral cavity, and oropharyngeal SCCs reported over the last decade in Brazil may have been diagnosed at the OMPLs included in the current study. Therefore, this data confirms the contribution of public OMPLs with respect to the important diagnostic support they provide to the oral healthcare services extended by the Brazilian Public Health System.

The use of deep learning state-of-the-art architectures for oral epithelial dysplasia grading: A comparative appraisal.

BACKGROUND: Dysplasia grading systems for oral epithelial dysplasia are a source of disagreement among pathologists. Therefore, machine learning approaches are being developed to mitigate this issue. METHODS: This cross-sectional study included a cohort of 82 patients with oral potentially malignant disorders and correspondent 98 hematoxylin and eosin-stained whole slide images with biopsied-proven dysplasia. All whole-slide images were manually annotated based on the binary system for oral epithelial dysplasia. The annotated regions of interest were segmented and fragmented into small patches and non-randomly sampled into training/validation and test subsets. The training/validation data were color augmented, resulting in a total of 81,786 patches for training. The held-out independent test set enrolled a total of 4,486 patches. Seven state-of-the-art convolutional neural networks were trained, validated, and tested with the same dataset. RESULTS: The models presented a high learning rate, yet very low generalization potential. At the model development, VGG16 performed the best, but with massive overfitting. In the test set, VGG16 presented the best accuracy, sensitivity, specificity, and area under the curve (62%, 62%, 66%, and 65%, respectively), associated with the higher loss among all Convolutional Neural Networks (CNNs) tested. EfficientB0 has comparable metrics and the lowest loss among all convolutional neural networks, being a great candidate for further studies. CONCLUSION: The models were not able to generalize enough to be applied in real-life datasets due to an overlapping of features between the two classes (i.e., high risk and low risk of malignization).

Gingival neoplasms: a multicenter collaborative study of 888 patients in Brazil

Background: To evaluate the prevalence and clinicopathological features of a large series of gingival neoplasms in Brazil. Material and methods: All gingival benign and malignant neoplasms were retrieved from the records of six Oral Pathology Services in Brazil, during a 41-year period. Clinical and demographic data, clinical diagnosis, and histopathological data were collected from the patients' clinical charts. For statistical analysis, the chi-square, median test of independent samples and the U Mann-Whitney tests were used, considering a significance of 5%. Results: From 100,026 oral lesions, 888 (0.9%) were gingival neoplasms. There were 496 (55.9%) males, with a mean age of 54.2 years. Most cases (70.3%) were malignant neoplasms. Nodules (46.2%) and ulcers (38.9%) were the most common clinical appearance for benign and malignant neoplasms, respectively. Squamous cell carcinoma (55.6%) was the most common gingival neoplasm, followed by squamous cell papilloma (19.6%). In 69 (11.1%) malignant neoplasms, the lesions were clinically considered to be inflammatory or of infectious origin. Malignant neoplasms were more common in older men, appeared with larger size, and with a time of complaint shorter than benign neoplasms (p<0.001). Conclusions: Benign and malignant tumors may appear as nodules in gingival tissue. In addition, malignant neoplasms, especially squamous cell carcinoma, should be considered in the differential diagnosis of persistent single gingival ulcers. (AU)

Symptomatic subgemmal neurogenous plaque in patients with COVID-19: Is there an association?

BACKGROUND: Subgemmal neurogenous plaques (SNP) are composed of neural structures found in the posterolateral portion of the tongue, rarely biopsied as most of them are asymptomatic or eventually only clinically managed. We aimed to investigate a case series of possible correlation of symptomatic subgemmal neurogenous plaque (SNP) with coronavirus disease 2019 (COVID-19). METHODS: Eleven formalin-fixed paraffin-embedded cases from patients with previous confirmed COVID-19 (by RT-PCR) were retrieved from two pathology files. Histological sections were morphologically studied, and then submitted to immunohistochemical reactions against S-100 and neurofilament proteins, neuron-specific enolase, Glial fibrillary acidic protein (GFAP), synaptophysin, CD56, Ki67, cytokeratins (7, 8-18, 19, 20), nucleocapsid and spike proteins (SARS-CoV-1; and -2) and epithelial membrane antigen (EMA) antibodies. Clinical data were retrieved from the patients' medical files, including the symptoms and the complete history of the progression of the disease. RESULTS: The patients who had COVID-19 included in this study experienced painful lesions in the tongue that corresponded to prominent or altered SNP. Microscopically, neural structures were positive for S-100, GFAP and neurofilament protein. And the cellular proliferative index (by Ki-67) was very low. CONCLUSION: Thus, based on the current results, we hypothesize that symptomatic SNP may be a late manifestation of COVID-19 infection.

Machine learning for detection and classification of oral potentially malignant disorders: A conceptual review.

Oral potentially malignant disorders represent precursor lesions that may undergo malignant transformation to oral cancer. There are many known risk factors associated with the development of oral potentially malignant disorders, and contribute to the risk of malignant transformation. Although many advances have been reported to understand the biological behavior of oral potentially malignant disorders, their clinical features that indicate the characteristics of malignant transformation are not well established. Early diagnosis of malignancy is the most important factor to improve patients' prognosis. The integration of machine learning into routine diagnosis has recently emerged as an adjunct to aid clinical examination. Increased performances of artificial intelligence AI-assisted medical devices are claimed to exceed the human capability in the clinical detection of early cancer. Therefore, the aim of this narrative review is to introduce artificial intelligence terminology, concepts, and models currently used in oncology to familiarize oral medicine scientists with the language skills, best research practices, and knowledge for developing machine learning models applied to the clinical detection of oral potentially malignant disorders.

Synchronous jawbone diseases: a multicenter retrospective study.

The aim of this study is to report an original case series of synchronous jawbone diseases. Data of patients seen over 13 years were extracted from the files of three Oral Radiology and Pathology diagnostic centers in Brazil. The clinical, radiographic, and laboratory characteristics were tabulated and analyzed by the authors; the patients were described according to lesion type. Seventy-two synchronous jawbone diseases were included in this study. Florid osseous dysplasia, Gorlin-Goltz syndrome, and cherubism were the most frequent disorders reported in this case series. In addition, the posterior mandible area was the main site of manifestation. Florid osseous dysplasia and Gorlin-Goltz syndrome represented two-thirds of our samples. With the utilization of adequate demographic, clinical, and radiologic information, it is possible to diagnose most of the synchronous lesions of jawbones. Sometimes, however, we need complementary exams, such as histopathologic and biochemical analysis or dosing of calcium, phosphorus, and alkaline phosphatase.

Synchronous jawbone diseases: a multicenter retrospective study

Abstract The aim of this study is to report an original case series of synchronous jawbone diseases. Data of patients seen over 13 years were extracted from the files of three Oral Radiology and Pathology diagnostic centers in Brazil. The clinical, radiographic, and laboratory characteristics were tabulated and analyzed by the authors; the patients were described according to lesion type. Seventy-two synchronous jawbone diseases were included in this study. Florid osseous dysplasia, Gorlin-Goltz syndrome, and cherubism were the most frequent disorders reported in this case series. In addition, the posterior mandible area was the main site of manifestation. Florid osseous dysplasia and Gorlin-Goltz syndrome represented two-thirds of our samples. With the utilization of adequate demographic, clinical, and radiologic information, it is possible to diagnose most of the synchronous lesions of jawbones. Sometimes, however, we need complementary exams, such as histopathologic and biochemical analysis or dosing of calcium, phosphorus, and alkaline phosphatase.

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

Abstract 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. Of the 120,010 oral and maxillofacial biopsies (2010-2019), 6.9% (8,321 cases) were diagnosed as lip (0.8%, 951 cases), oral cavity (4.9%, 5,971 cases), and oropharyngeal (1.2%, 1,399 cases) SCCs. Most cases were from Brazil's Southeast (64.5%), where six of the OMPLs analyzed are located. The predominant profile of patients with lip and oral cavity SCC was Caucasian men, with a mean age over 60 years, low schooling level, and a previous history of heavy tobacco consumption. In the oropharyngeal group, the majority were non-Caucasian men, with a mean age under 60 years, had a low education level, and were former/current tobacco and alcohol users. According to data from the Brazilian National Cancer Institute, approximately 9.9% of the total lip, oral cavity, and oropharyngeal SCCs reported over the last decade in Brazil may have been diagnosed at the OMPLs included in the current study. Therefore, this data confirms the contribution of public OMPLs with respect to the important diagnostic support they provide to the oral healthcare services extended by the Brazilian Public Health System.

Oral follicular lymphoma: a clinicopathologic and molecular study.

Follicular lymphoma is a hematolymphoid neoplasm that originates from germinal center B cells. It is made up of a combination of small cleaved centrocytes and a varying quantity of larger non-cleaved centroblasts to describe the clinical, microscopic, immunohistochemical, and molecular features of oral follicular lymphomas. Follicular lymphomas affecting the oral cavity were retrieved from pathology files. Immunohistochemistry was performed to confirm the diagnosis, and fluorescence in situ hybridization (FISH) was employed to detect rearrangements in BCL2, BCL6, and MYC genes. Clinical and follow-up data were obtained from the patient's medical and pathology files. Twenty cases were obtained. There was an equal sex distribution (10 males: 10 females) and a mean age of 60.9 years (range: 10-83 years-old). Lesions presented as asymptomatic swellings, usually in the palate (10 cases) and the buccal mucosa (7 cases). Five patients presented with concomitant nodal involvement. Microscopic evaluation depicted the follicular growth pattern with diffuse areas in six cases. Grades 1 and 2 follicular lymphomas represented 12 cases, while grade 3A neoplasms accounted for other 8 cases. Two cases showed rearrangements in MYC, BCL2, and BCL6 genes, while single BCL2 translocation was found in eight cases. Two cases had no translocation. Three patients deceased and the 2-year overall survival achieved 88%. Follicular lymphoma affecting the oral cavity is uncommon, usually affects the palate as a non-ulcerated swelling and the presence of a systemic disease most always be ruled out.

Oral and maxillofacial manifestations of IgG4-related disease: A clinicopathological study.

BACKGROUND: IgG4-related disease is a fibroinflammatory and immune-mediated condition, which has extremely variable clinical manifestations. In this study, we aim to investigate the clinicopathological features of IgG4-related disease involving the oral and maxillofacial region. METHODS: Cases of IgG4-related disease manifesting in the oral and maxillofacial region were retrieved from three Brazilian institutions. Clinical and serological data were obtained from the patients' medical charts, while microscopic and immunohistochemical findings were revised by oral pathologists. Diagnosis followed the American College of Rheumatology/European League against Rheumatism criteria. RESULTS: Seven patients diagnosed with IgG4-related disease were included in this study. Women were affected in all analysed cases, with a mean age of 55.4 years. Two patients presented with the clinical involvement of more than one oral and maxillofacial anatomic site. Therefore, our sample comprised nine oral and maxillofacial anatomic sites affected by IgG4-related disease. The submandibular gland was affected in four cases, the tongue and the parotid gland in two cases each, and the palate in one case. In a few cases, exploratory lower lip biopsy was used as a diagnostic approach. A moderate-to-severe lymphoid infiltrate containing plasma cells and lymphocytes, with an increased IgG4/IgG ratio, was common. Treatment varied and steroids were the most frequently used (57.4%). Six patients remained alive, while one died from unknown causes. CONCLUSION: Although major salivary glands are commonly affected by IgG4-related disease, the oral cavity can also be involved, and lower lip biopsy may be an auxiliary diagnostic tool.

HIV-related non-Hodgkin lymphomas affecting the oral cavity: a clinicopathologic study of 11 cases

Background: HIV-related non-Hodgkin lymphomas of the oral cavity are rare lesions with aggressive clinical behaviour. The aim of this study is to describe the clinicopathological features of a series of HIV-related oral non-Hodgkin lymphomas. Material and Methods: Eleven cases of oral lymphomas affecting HIV-positive patients were retrieved from 2012 to 2019. Clinicopathological features regarding age, sex, tumour location, clinical presentation, laboratory findings, disease stage and follow-up were obtained. Histologic, immunohistochemical and in situ hybridization for EBV detection were done for diagnosis confirmation. Overall survival was estimated by Kaplan–Meier curve. Results: Males predominated, with a mean age of 40.3 years-old. Maxilla and mandible were the mostly affected. Plasmablastic lymphoma and diffuse large B-cell lymphoma not otherwise specified (NOS) were the main histological types. Lesions presented as reddish ulcerated swellings, representing the first sign of AIDS in six cases. Stage IV were common (7 cases) and the mean HIV viral load was 10,557 copies/mL, with a mean of 266 CD4+ cells/mm3, 1,278 CD8+ cells/mm3 and a CD4+/CD8+ ratio of 0.26. Eight patients died of the disease (72.7%). Overall survival revealed that 78.2% of the patients died after 21 months of follow-up. Conclusions: HIV-related oral lymphomas present a poor prognosis usually diagnosed in advanced stages and in our series plasmablastic lymphoma was the most common subtype.(AU)

Hybrid odontogenic lesions: A systematic review of 203 cases reported in the literature.

BACKGROUND: Hybrid odontogenic lesions combine histopathological characteristics of two or more odontogenic cysts and/or tumours. The aim of this study was to evaluate the available data on hybrid odontogenic lesions (HOL) and to analyse their epidemiological/clinical features and biological behaviour. METHODS: An electronic search was done in January 2021 using multiple databases. Eligibility criteria encompassed publications with sufficient clinical and histological information to confirm the tumours' diagnoses. RESULTS: A total of 147 articles were included in this study, comprising 203 cases. Calcifying odontogenic cyst associated with odontoma (COC/OD) (37/18.2%) was the most common HOL. Females were more affected with a mean age of 24.9 years. Lesions presented as asymptomatic swellings, with a mean evolution time of 8.2 months (0.3-96), and mean tumour size of 4.8 cm (0.3-7). Radiographic aspects frequently showed radiolucent (139/68.4%) and unilocular (52/25.6%) images with well-defined limits (48/23.6%). The lesions mostly affected mandibular pre-molars (69/34%) and mandibular molars (69/34%) regions. Enucleation (89/43.8%) and surgical excision (59/29%) were the most common treatment modalities. The mean follow-up time was 33.8 months (0.5-216 months) and recurrences were observed in four cases (1.9%), all of which were central odontogenic fibroma associated with central giant cell granuloma (COF/CGCG). CONCLUSION: COC/OD is the most common HOL and recurrence is a rare event, being usually associated with the diagnosis of COF/CGCG.

What is the frequency of floor of the mouth lesions? A descritive study of 4016 cases / ¿Cuál es la frecuencia de las lesiones del suelo de la boca? Un estudio descriptivo de 4016 casos

Background: The aim of this study was to investigate the frequency of oral lesions in the floor of the mouth fromrepresentative oral pathology centres in Latin America.Material and Methods: This study was conducted on biopsies obtained from January of 1978 to December of 2018at nine Latin America oral and maxillofacial pathology centres. Gender, age and histopathological diagnosis wereevaluated. Data were analysed using descriptive methods. Chi-square test was used for pairwise comparisons.Results: From 114,893 samples, 4,016 lesions (3.49%) occurred in the floor of the mouth. Brazil showed 3,777 cases(94%), Mexico 182 cases (4.5%) and Argentina 57 cases (1.4%). Benign lesions represented 65.1% (2,617 cases),followed by 34.9% (1,404 cases) of malignant disorders. Lesions of epithelial origin were more frequent (1,964) cases; 48.9%), followed by salivary glands (1,245 cases; 31%) and soft tissue lesions (475 cases; 11.7%). The mostcommon histological subtypes were oral squamous cell carcinoma (1,347 cases; 33.5%), ranula (724 cases; 18%), oralleukoplakia (476 cases; 11.8%) and inflammatory fibrous hyperplasia (239 cases; 5.9%). The lesion affected males in2,129 cases and females in 1,897 cases.Conclusions: In the current study, lesions in the floor of the mouth represented 3.49% of biopsies submitted to oralpathology services and oral squamous cell carcinoma, ranula and leukoplakia were the most common lesions.(AU)

Oral Kaposi sarcoma development is associated with HIV viral load, CD4+ count and CD4+/CD8+ ratio / El desarrollo del sarcoma de Kaposi oral está asociado con carga viral de VIH, recuento de CD4+ y relación CD4+/CD8+

Background: Kaposi’s sarcoma (KS) is an uncommon, multifocal and angioproliferative lesion, which demon-strates a poor prognosis. The aim of the present research was to explore the association of HIV viral load, CD4+and CD8+ counts and the CD4+/CD8+ ratio on the risk of oral Kaposi’s sarcoma (KS) development.Material and Methods: A total of 62 patients were retrieved from March 2008 to October 2020 from the files oftwo oral pathology centres. Clinical, laboratory and follow-up data were retrieved from their medical files. Poissonregression was used to explore the role of history of immunosuppression and its association with oral KS develop-ment. A P-value <0.05 was considered significant.Results: Sixty-two patients were included in the present study (32 with oral KS and 30 with no presentation oflesions anywhere on the body). Patients with oral KS presented a mean age of 32.6 years, and male patients weremore affected. The hard palate (15 cases; 46.8%) was the main anatomical site affected. The lesions were mostlypresented as swellings (13 cases; 40.6%) and nodules (12 cases; 37.5%). Systemic manifestations were also ob-served, including candidiasis (4 cases; 12.5%), bacterial infection (3 cases; 9.3%), tuberculosis (3 cases; 9.3%),herpes simplex (3 cases; 9.3%) and pneumonia (3 cases; 9.3%). A significant correlation was observed betweenHIV viral load, CD4+ count and the CD4+/CD8+ ratio with oral KS development.Conclusions: HIV viral load, CD4+ count and the CD4+/CD8+ ratio are associated with oral KS development.(AU)

Odontogenic Keratocyst in a 9-Month-Old Patient: A Case Report.

Odontogenic Keratocyst (OKC) is a benign, intraosseous, odontogenic cyst which originates from the basal cells of overlying epithelium or from the dental lamina remnants. Clinically, they are presented as asymptomatic swellings, although can sometimes be associated with pain. Growth of an OKC leads to expansion and destruction of bone as it infiltrates the tissue around it. It is commonly seen in males between the second and fourth decades of life. The aim of this study is to report on the clinicopathological characteristics of an odontogenic keratocyst in a 9-month-old female patient and posterior rehabilitation with a removable maxillary expander.

Plasmacytoma and plasma cell myeloma affecting the jaws: A multi-institutional collaborative study.

BACKGROUND: Plasma cell neoplasms are characterized by the proliferation of a single clone of plasma cells with production of a monoclonal immunoglobulin. They can manifest as a single lesion (plasmacytoma) or as multiple lesions (multiple myeloma). METHODS: Paraffin-embedded tissue blocks of patients microscopically diagnosed with plasma cell neoplasms in the jaws were retrieved from five pathology files. Data including clinical, radiographic, microscopic and immunohistochemical findings, treatment employed and follow-up status were retrieved from the pathology reports. RESULTS: Fifty-two cases were retrieved (mean age: 59.4 years) without sex predilection. The mandible was the most affected site (67.3%), usually associated with pain and/or paresthesia (53.8%). Lesions in other bones besides the jaws were reported for 24 patients (46.2%). Radiographically, tumours usually presented as poorly defined osteolytic lesions with unilocular or multilocular images, while microscopy revealed diffuse proliferation of neoplastic plasma cells with nuclear displacement and abundant eosinophilic cytoplasm. Two cases were classified as anaplastic, and amyloid deposits were found in two other cases. Immunohistochemistry was positive for plasma cell markers and negative for CD20 and CD3, and monoclonality for kappa light chain predominated. The overall survival rate after 5 years of follow-up was 26.6%. CONCLUSION: Plasma cell neoplasms are aggressive tumours with a poor prognosis and involvement of the jaws may be the first complaint of the patient. Thus, oral pathologists, head and neck surgeons and dentists should be aware of their clinical, radiographic and microscopic manifestations.

Oral and oropharyngeal lymphomas: A multi-institutional collaborative study.

BACKGROUND: Lymphomas in the oral and oropharyngeal regions are relatively uncommon, and their diagnosis is challenging and complex due to the myriad histopathological subtypes. Herein, we report a large series of oral and oropharyngeal lymphomas and compare our data with the currently available literature. METHODS: All cases diagnosed as lymphomas affecting the oral and oropharyngeal regions were retrospectively retrieved from seven Brazilian institutions. Clinicodemographic data and histopathological features were evaluated and described, while a comprehensive literature review was undertaken in order to compare our findings. RESULTS: A total of 304 cases of oral and oropharyngeal lymphomas were obtained, mostly affecting individuals aged 60-69 years (n = 68) with a mean age at diagnosis of 54.2 ± 20.1 years. Males and females were equally affected. Mature B-cell neoplasms (87.2%) were the most common group, followed by mature T- and NK-cell neoplasms (11.2%) and precursor lymphoid neoplasms (1.6%). The most frequent subtypes in each group were diffuse large B-cell lymphomas, not otherwise specified (n = 99), extranodal NK/T-cell lymphomas, nasal type (n = 12), and B-lymphoblastic leukaemia/lymphomas, not otherwise specified (n = 4). The most commonly involved sites were the palate (26.3%), mandible (13%), and maxilla (10.5%). CONCLUSION: Diffuse large B-cell lymphoma, not otherwise specified, remains the most common subtype of lymphomas in the oral and oropharyngeal region. Older patients are the most affected, with no gender predilection and the palate and jaw are usually affected.