Maxillofacial Pathology Services Research Articles

Oral lesions of systemic lupus erythematosus: A collaborative Latin American study.

Systemic lupus erythematosus (SLE) is a multifactorial autoimmune disease that may affect the oral mucosa. The variable spectrum of oral lesions observed in SLE can pose challenges in diagnosis, particularly when the lesions occur in isolation. The aim of this study was to describe the oral lesions occurring in patients with SLE from Latin America. This collaborative record-based study involving 11 oral and maxillofacial pathology and medicine services across Venezuela, Argentina, Chile, Brazil, and Mexico describes the clinicopathological profile of SLE-related oral lesions. Seventy patients with SLE and oral lesions were included in the study. The majority were females (75.7%; female/male ratio: 3.1:1) and white (62.1%), with a mean age of 38.4 years (range: 11-77 years). The most common site of oral lesions was the hard/soft palate (32.0%). Clinically, oral lesions predominantly presented as ulcers (26.6%), erosions (26.6%), and white lesions (23.4%). Isolated oral lesions occurred in 65.2% of individuals, while cutaneous manifestations occurred in 80.3%. The main clinical diagnostic hypothesis in 71.4% of cases was an immune-mediated disease. Oral biopsies followed by histopathological analysis were performed in 50 cases. Oral lesions of SLE exhibit a variety of clinical and histopathological features. A key point in diagnosis is that unusual oral changes without an obvious local cause may indicate a possible systemic condition presenting with oral lesions. A multidisciplinary approach, which includes regular oral examination, is warranted to identify oral lesions and provide treatment.

Xanthoma of the Jaw Bones: Cases Series and Review of Literature

BackgroundIntraosseous xanthomas are rare benign lesions sometimes associated with excess lipid production. Xanthoma of the jaw bones (XJB) was first reported in 1964, and fewer than 50 cases have been reported in the English literature to date. The etiopathogenesis of XJB is highly suggestive of a reactive process or a metabolic condition.MethodSeven cases of XJBs were retrieved from the archives of 4 oral and maxillofacial pathology services. Clinical, radiographic and histopathologic features of all these cases were retrospectively analyzed. Immunohistochemical (IHC) stains for S100 and CD68 were performed.ResultsAll seven cases involved the mandible. Patients’ age ranged between 13 and 69 years with an evenly distributed female to male ratio. One patient had a medical history of hyperlipidemia, but the medical and dental histories of the others were unremarkable. For most cases, XJB was an incidental finding discovered during routine radiographic examination. Swelling and cortical expansion were noted in a few cases. Radiographically, cases typically presented as either well-defined multilocular or unilocular lesions, which were either radiolucent or mixed radiolucent/radiopaque. All the lesions were treated with surgical curettage and no recurrence was observed during subsequent follow-ups. Each of the seven cases exhibited sheets of foamy macrophages. The diagnosis is established by exclusion of entities with overlapping microscopic features and involved correlation with the clinical, histological, radiographic and IHC profiles. Immunohistochemically, all the cases expressed diffuse positivity for CD68 and were negative for S100.ConclusionXJB is a rare lesion of unknown etiology, which may mimic other benign or reactive jaw lesions. Due to its rarity and the potential diagnostic challenges it presents, clinicians must remain vigilant and consider CXJ in their differential when assessing radiolucent jaw anomalies.

ANGINA BULLOSA HEMORRHAGICA OF THE ORAL CAVITY: A 14-YEAR RETROSPECTIVE STUDY IN A BRAZILIAN POPULATION

Objectives To report the clinical features of angina bullosa hemorrhagica (ABH) cases, emphasizing the clinical and therapeutic characteristics. Study Design A retrospective descriptive cross‐sectional study was performed in 3 oral and maxillofacial pathology services and 1 private practice in Brazil. Clinical data were collected from the clinical records and evaluated. Results The series comprised 12 males (52.2%) and 11 females (47.8%), with a mean age of 56.8 ± 14.6 years. Most of the lesions affected the soft palate (n = 15, 65.2%) and tongue (n = 6, 26.1%). Clinically, the lesions presented mainly as an asymptomatic (n = 17, 73.9%) blood-filled blister that ruptured after a few minutes or hours, leaving an erosion. When specified, the masticatory trauma was the most frequent triggering event. No individual had coagulation disorders. Treatment was symptomatic with a favorable outcome. Conclusions ABH is still poorly documented in the literature, and its etiology remains uncertain. ABH mainly affects the soft palate of elderly adults and has a favorable evolution in a few days. However, it can share some clinical features with more serious diseases. Therefore, a careful clinical examination is essential to rule out possible autoimmune or hematologic disorders. To report the clinical features of angina bullosa hemorrhagica (ABH) cases, emphasizing the clinical and therapeutic characteristics. A retrospective descriptive cross‐sectional study was performed in 3 oral and maxillofacial pathology services and 1 private practice in Brazil. Clinical data were collected from the clinical records and evaluated. The series comprised 12 males (52.2%) and 11 females (47.8%), with a mean age of 56.8 ± 14.6 years. Most of the lesions affected the soft palate (n = 15, 65.2%) and tongue (n = 6, 26.1%). Clinically, the lesions presented mainly as an asymptomatic (n = 17, 73.9%) blood-filled blister that ruptured after a few minutes or hours, leaving an erosion. When specified, the masticatory trauma was the most frequent triggering event. No individual had coagulation disorders. Treatment was symptomatic with a favorable outcome. ABH is still poorly documented in the literature, and its etiology remains uncertain. ABH mainly affects the soft palate of elderly adults and has a favorable evolution in a few days. However, it can share some clinical features with more serious diseases. Therefore, a careful clinical examination is essential to rule out possible autoimmune or hematologic disorders.

ODONTOGENIC GLANDULAR CYST: A COLLABORATIVE INVESTIGATION OF 22 CASES AND PROTEINS RELATED TO INVASIVENESS

<h3>Objectives</h3> To carry out a multicenter retrospective study on the clinical, demographic, microscopic, and immunohistochemical characteristics of the glandular odontogenic cyst (GOC), emphasizing histopathologic characteristics and expression of proteins related to invasiveness. <h3>Study Design</h3> Twenty-two cases of GOC from 3 oral and maxillofacial pathology services of federal universities in Brazil from 1988 to 2018were selected. Clinical and demographic data were collected. Histopathologic features were evaluated. Additionally, 16 cases of GOC were submitted to immunohistochemistry to detect MT1-MMP, TKs4, TKs5, and cortactin, key regulators of invadopodia formation. <h3>Results</h3> Cases of GOC mainly affect men over 40 years old, are mainly in the posterior mandible and anterior maxilla, and present as multilocular radiolucent lesions. Of 10 important histopathologic parameters to be evaluated in GOCs, "hobnail" cells, clear cells, and variable thickness of the lining epithelium were present in all cases. Immunohistochemistry revealed greater expression of the studied proteins related to invasiveness when compared to controls (<i>P</i> < .0001). <h3>Conclusions</h3> This study characterized clinical-demographic data, histopathologically investigated cases of COG, and identified overexpression of proteins that regulate cell invasiveness. These findings suggest invadopodia activity as a possible mechanism used by COG for promoting local invasion, which could partly explain its intriguing biological behavior.

Glandular odontogenic cysts: A collaborative investigation of 22 cases and proteins related to invasiveness.

A glandular odontogenic cyst (GOC) has an intriguing, aggressive behaviour whose mechanisms have not yet been clarified. To conduct a collaborative cross-sectional study on the clinical, demographic, microscopic and immunohistochemical characteristics of GOCs, emphasizing the histopathological characteristics and expression of proteins related to invasiveness. Twenty-two cases of GOC from three oral and maxillofacial pathology services in Brazil were selected from 1988 to 2018. Clinical and demographic data were collected. Histopathological features were evaluated in detail. Sixteen cases of GOC were also submitted to immunohistochemistry to detect MT1-MMP, TKS4, TKS5 and cortactin, the key regulators of invadopodia formation. Glandular odontogenic cysts were primarily seen in men over 40years of age, in the posterior mandible and the anterior maxilla as a unilocular, radiolucent lesion. All cases presented hobnail cells, clear cells and variable thickness of the lining epithelium, 3 of the 10key histopathological parameters to be evaluated in GOCs. Immunohistochemistry revealed a greater expression of the studied proteins in the GOCs than in the controls (p<0.0001). Overexpression of proteins that regulate cell invasiveness was identified, and the present study's findings suggest that invadopodia activity is a possible mechanism used by GOCs to promote local invasion, which could partly explain its intriguing biological behaviour.

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

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. A retrospective descriptive cross-sectional study was performed. A total of 54,190 biopsy records of oral and maxillofacial lesions from four oral and maxillofacial pathology services in Brazil were analysed. All cases of lipomas were reviewed, and clinical, demographic and histopathological data were collected of all cases compatible with sialolipomas. In addition, immunohistochemistry stains (AE1/AE3, CK7, 34βE12, S-100, HHF35, α-SMA and Ki-67) and a literature review based on a search of three electronic databases (PubMed, Web of Science and Scopus) were performed. Among all lipomas reviewed, there were 10 cases of sialolipomas. The series comprised of 7 females (70.0%) and 3 males (30.0%), with a mean age of 46.1±21.5years (range: 11-71years) and a 2.3:1 female-to-male ratio. The lower lip (n=3, 30.0%) and tongue (n=2, 20.0%) were the most common locations, presenting clinically as a nodule of slow growth and normal colour. Conservative surgical excision was the treatment in all cases. No recurrence was observed. Sialolipomas are a rare histological variant of lipoma, affecting the salivary glands, mainly in the parotid gland and palate of female adults. Pathologists must recognise sialolipomas to avoid misdiagnoses with other lipomatous tumours that can affect salivary glands.

Clinicopathologic features of nasopalatine duct cysts: A retrospective study in two Brazilian oral and maxillofacial pathology referral centers.

Background Nasopalatine duct cyst (NDC) is the most common non-odontogenic cyst in the oral cavity. Clinically it is not difficult to suspect these lesions based on clinical and radiographic appearance. However, the histopathological diagnosis may be difficult due to the broad morphological diversity of these lesions. The objective was to analyze the clinicopathological features of NDCs diagnosed in two oral and maxillofacial pathology services in the Brazilian northeast.Material and Methods A retrospective clinicopathologic study was performed. A total of 18,121 clinical records of oral lesions from two oral and maxillofacial pathology services in Brazil were analyzed (2000-2020). All NDCs cases were revised and demographic, clinical, radiographic, and histopathological data were collected.Results Among 18,121 diagnoses in the oral pathology services, 45 (0.2%) were NDCs. The series comprises 24 males (53.3%) and 21 females (46.7%), with a mean age of 43.2 years-old. Most lesions were asymptomatic (n = 27, 60%) with an mean size of 2.1 cm. Microscopically, the non-keratinized stratified squamous epithelium was the most common (66.7%). However, in 88.9% of cases, the epithelial lining was varied and composed of two or more types of epithelium. There was no significant association between the type of epithelium and the size of the cysts (p = 0.389). Nerve, blood vessels, hemorrhage, and chronic inflammatory infiltrate were commonly observed. In contrast, there was a low frequency of mucous glands, sebaceous glands, cholesterol clefts, and multinucleated giant cells.Conclusions The clinical, radiographic, and microscopic findings observed in this study are similar to those reported in the literature. Due to the morphological diversity of NDC, it is needed to correlate its histopathological features with the clinical and radiographic findings to establish a correct diagnosis. Key words:Oral cavity, oral pathology, nonodontogenic cysts, diagnosis.

Primary melanoma of the oral cavity: A multi-institutional retrospective analysis in Brazil.

Background Melanoma is an aggressive malignant tumor, rarely observed in the oral cavity. The aim of this study was to describe the clinicopathologic features of a series of oral melanomas. Material and Methods A retrospective descriptive study was performed. A total of 15,482 biopsy records from two oral and maxillofacial pathology services in Brazil were analyzed. All cases of oral melanomas were reviewed, and clinical, demographic, histopathological data, treatment, and follow-up status were collected. In addition, immunohistochemistry stains (pan-cytokeratin AE1/AE3, vimentin, α-SMA, CD45, S-100 protein, HMB-45, Melan A, and Ki-67) were performed. Results The series comprised of 5 males (71.4%) and 2 females (28.6%), with a mean age of 58.0 ± 9.2 years (range: 45-69 years) and a 2.5:1 male-to-female ratio. The gingiva (n = 3, 42.8%) and hard palate (n = 2, 28.6%) were the most common affected sites, presenting clinically as ulcerated swellings with a brown to black color. Cervical lymph node metastasis was detected in three patients during the first examination. Microscopically, 6 cases (85.7%) were melanotic, and one (14.3%) was amelanotic. Most cases (n = 4, 57.1%) presented a predominance of epithelioid cells. S-100 and HMB-45 were positive in all cases (n = 7, 100.0%). In contrast, only 4 cases (57.1%) were positive for Melan-A. The proliferative index with Ki-67 was high, with labeling index ranging from 70.0% to more than 90% of positive cells. Five patients died from complications of the tumors after a mean follow-up period of 7.8 months. Conclusions Melanoma is an aggressive malignant tumor that rarely occurs in the oral cavity. It occurs mainly in adult and elderly patients and often is diagnosed in advanced stages. The current findings were similar to previous studies and reflected the characteristics of the services from where lesions were retrieved. Key words:Head and neck cancer, melanoma, oral melanoma, oral mucosa.

Oral focal mucinosis: A multi-institutional study and literature review.

Oral focal mucinosis (OFM) is a rare benign condition of unknown etiology, considered the oral counterpart of cutaneous focal mucinosis. We report the clinicopathologic features of 21 cases of OFM in conjunction with a review of the literature. Clinical data were collected from the records of five oral and maxillofacial pathology services. All cases were evaluated by hematoxylin and eosin staining, histochemistry, and immunohistochemistry (vimentin, S-100, α-SMA, CD34, and mast cell). The series comprised 14 females (66.7%) and seven males (33.3%), with a mean age of 48.2 ± 20.7 years (range: 8-77 years) and a 2:1 female-to-male ratio. Most of the lesions affected the gingiva (n = 6, 28.6%) and presented clinically as asymptomatic sessile or pedunculated nodules with fibrous or hyperplasic appearance. All cases were negative for S-100 protein, CD34, and α-SMA and positive for Alcian blue staining. Conservative surgical excision was the treatment in all cases, and there was only one recurrence. OFM is a rare benign disorder that is often clinically misdiagnosed as reactive lesions or benign proliferative processes. Dermatologists and pathologists should consider OFM in the differential diagnosis of soft tissue lesions in the oral cavity, mainly located in the gingiva.

INTRAOSSEOUS XANTHOMA OF THE MANDIBLE: A MULTICENTER STUDY OF 5 CASES

The aim of this study was to report the clinicopathologic, radiographic, and immunohistochemical features of 5 cases of intraosseous xanthomas of the mandible. Clinical data were collected from records of 3 oral and maxillofacial pathology services in South America. All cases were evaluated by conventional staining with hematoxylin and eosin and immunohistochemistry including CD68 and S-100. The series included 4 females (80%) and 1 male (20%), with a mean age of 23.3 years (range, 13 to 45 years). All cases affected the mandible with predilection for the posterior region (80%). Most lesions presented radiographically as radiolucent (80%) with punched-out margin (80%) and unilocular structure (60%). Immunohistochemistry demonstrated positivity for CD68 and negativity for S-100 in xanthomatous cells in all cases. Recurrences were not observed after complete surgical removal by curettage, with a median follow-up of 27 months. The aim of this study was to report the clinicopathologic, radiographic, and immunohistochemical features of 5 cases of intraosseous xanthomas of the mandible. Clinical data were collected from records of 3 oral and maxillofacial pathology services in South America. All cases were evaluated by conventional staining with hematoxylin and eosin and immunohistochemistry including CD68 and S-100. The series included 4 females (80%) and 1 male (20%), with a mean age of 23.3 years (range, 13 to 45 years). All cases affected the mandible with predilection for the posterior region (80%). Most lesions presented radiographically as radiolucent (80%) with punched-out margin (80%) and unilocular structure (60%). Immunohistochemistry demonstrated positivity for CD68 and negativity for S-100 in xanthomatous cells in all cases. Recurrences were not observed after complete surgical removal by curettage, with a median follow-up of 27 months.

Oral pigmented lesions: a retrospective analysis from Brazil.

Background Pigmented lesions are uncommon in the oral mucosa, and studies investigating the incidence and types of these lesions are desired to improve the diagnostic knowledge of clinicians. The aim of this study was to analyze the distribution of oral pigmented lesions in a Brazilian population. Material and Methods A retrospective descriptive cross-sectional study was performed. Oral pigmented lesions were retrieved from the files of two oral and maxillofacial pathology services from Brazil over a 45-year period (1974-2019). The clinical data and the diagnoses of each case were retrieved and included in a Microsoft Excel® database. Results From 77.074 lesions diagnosed in this period, 761 (0.99%) represented pigmented lesions of the oral mucosa, including 351 (46.1%) melanocytic and 410 (53.9%) non-melanocytic lesions, with a higher incidence in females (73.2%) between the fourth and seventh decades of life. Amalgam tattoo (53.6%) represented the most common lesion, followed by melanotic macule (18.3%) and racial pigmentation (10.8%). Other pigmented lesions included nevus (9.9%), post-inflammatory pigmentation (3%), melanoma (2.1%), melanoacanthoma (1.4%), smoker's melanosis (0.4%), drug-induced pigmentation (0.3%), and melanotic neuroectodermal tumor of infancy (0.1%). The buccal mucosa was the most commonly affected site (25.2%), followed by the alveolar ridge (14.5%), and gingiva (11.8%). Conclusions The current findings were similar to previous studies with minor differences due methodology and characteristics of the services from where lesions were retrieved. The knowledge of these data may contribute to a better understanding of oral pigmented lesions and assist clinicians to better recognize and manage them. Key words:Pigmented lesions, pigmentation, melanin, amalgam, oral cavity.

MALIGNANT PERIPHERAL NERVE SHEATH TUMOR: A BRAZILIAN COLLABORATIVE STUDY OF 4 CASES

Objective Malignant peripheral nerve sheath tumor (MPNST) is an extremely rare malignancy in the oral cavity. It is derived from peripheral nerves and can display the differentiation of nerve sheath elements. This study investigated the frequency of MPNST that has been submitted for microscopic examination from 2 Brazilian oral and maxillofacial pathology services. Study Design A retrospective study was conducted on biopsies obtained from 1954 to April 2018 at 2 Brazilian oral and maxillofacial pathology services. A total of 43,915 biopsy specimens were analyzed. Demographic data and histopathologic diagnosis were evaluated descriptively. Results A total of 4 cases of MPNST were surveyed, representing 0.009% of the oral lesions at the centers studied. MPNST was diagnosed in 3 males and 1 female. The mean age ± SD was 37.7 ± 15.9 (range 16-61) years. Two of the 4 lesions occurred in the maxilla and the mean of evolution time was 10.2 months. Immunohistochemical analysis revealed positivity of neoplasms cells for S-100, vimentin, and glial fibrillary acidic protein (GFAP). Conclusions This study has contributed to the improvement of the epidemiology, prognostic markers, and outcomes of this malignancy. The differential diagnosis of the MPNST may be facilitated by additional information obtained from immunohistochemistry findings. Support: FAPEMIG.

MULTICENTER STUDY OF CALCIFYING EPITHELIAL ODONTOGENIC TUMOR: ANALYSIS OF 27 CASES AND REVIEW OF LITERATURE

Objective To investigate the frequency of calcifying epithelial odontogenic tumor (CEOT) that has been submitted for microscopic examination from representative geographic regions of Brazil and to compare it with literature data. Study Design A retrospective study was conducted on biopsy results obtained from 1953-2016 at 5 Brazilian oral and maxillofacial pathology services. A total of 84,668 biopsy specimens were analyzed. Demographic data, histopathologic diagnosis, treatment, and follow-up period were evaluated descriptively. A literature search was performed in PubMed for articles on CEOT published from 1958 to April 2018. Results A total of 27 cases of CEOT were surveyed, representing 0.03% of the oral lesions at the centers studied. A slight prevalence for female patients was observed in their second and fourth decades of life. Mandible was the most affected site. Conservative surgery was the most frequent treatment accomplished with mean of follow-up time of 68.7 months. The literature review showed a higher frequency in Asian individuals. Conclusion CEOT is an extremely rare lesion. Novel data on the clinicopathologic features of 27 cases have been added to the literature. Data of the Brazilian patients reported herein are in agreement with findings of case series reported elsewhere. Support: FAPEMIG. To investigate the frequency of calcifying epithelial odontogenic tumor (CEOT) that has been submitted for microscopic examination from representative geographic regions of Brazil and to compare it with literature data. A retrospective study was conducted on biopsy results obtained from 1953-2016 at 5 Brazilian oral and maxillofacial pathology services. A total of 84,668 biopsy specimens were analyzed. Demographic data, histopathologic diagnosis, treatment, and follow-up period were evaluated descriptively. A literature search was performed in PubMed for articles on CEOT published from 1958 to April 2018. A total of 27 cases of CEOT were surveyed, representing 0.03% of the oral lesions at the centers studied. A slight prevalence for female patients was observed in their second and fourth decades of life. Mandible was the most affected site. Conservative surgery was the most frequent treatment accomplished with mean of follow-up time of 68.7 months. The literature review showed a higher frequency in Asian individuals. CEOT is an extremely rare lesion. Novel data on the clinicopathologic features of 27 cases have been added to the literature. Data of the Brazilian patients reported herein are in agreement with findings of case series reported elsewhere. Support: FAPEMIG.

DENTINOGENIC GHOST CELL TUMOR: A COLLABORATIVE STUDY OF 10 CASES AND LITERATURE REVIEW

Objective To investigate the frequency of dentinogenic ghost cell tumor (DGCT) that has been submitted to microscopic examination from representative geographic regions of Brazil and to compare it with literature data. Study Design A retrospective study was conducted on biopsy results obtained from 1953-2016 at 6 Brazilian oral and maxillofacial pathology services. A total of 84,668 biopsy specimens were analyzed. Demographic data and histopathologic diagnosis were evaluated descriptively. A literature search was performed in PubMed/MEDLINE for articles about DGCT published from 1933-2017. Results A total of 10 cases of DGCT were identified across the sample. Most individuals were male patients (60%) and ranged in age from 12 to 64 years (mean, 27.6 years). The most frequent location was the mandible (66.3%), and most of patients were asymptomatic (62.5%). The literature review showed a higher frequency in Asia and North America, mainly affecting men in the fifth decade of life. Conclusion DGCT is an extremely rare lesion. Data regarding age of the Brazilian patients reported here differ with findings from cases reported elsewhere. Support: FAPEMIG

Intraosseous xanthoma of the mandible: A multi-institutional case series with a literature review.

The aim of the present study was to report the clinicopathologic, radiographic and immunohistochemical features of five South American cases of intraosseous xanthomas of the mandible and to compare them to those detected in a literature review. Clinical data were collected from the records of three Oral and Maxillofacial Pathology services in South America and compared with those compiled from a literature review based on a search of three electronic databases (PubMed, Web of Science and Scopus). All cases were evaluated by haematoxylin and eosin staining and immunohistochemistry for CD68 and S-100. The series comprised four females (80%) and one male (20%) with a mean age of 23.3±10.9years (range: 13-45years). In four cases, there was involvement of the posterior region of the mandible (80%). The lesions presented radiographically as unilocular (60%) radiolucencies with punched-out margin (80%). All cases predominantly consisted of CD68-positive and S-100-negative xanthomatous cells. No recurrences were observed after curettage, with a median follow-up of 27months. Intraosseous xanthoma of the jaws is a rare benign disorder. We report here five additional cases affecting the mandible, for a total of 36 cases of the jaws reported in the literature. Overall, this lesion has predilection for posterior sites of the mandible of asymptomatic young adults.

USP6 GENE REARRANGEMENT TESTING OF GNATHIC ANEURYSMAL BONE CYSTS: A MULTICENTER ANALYSIS OF TEN CASES

Background The jaws are an uncommon location for primary aneurysmal bone cysts (ABCs), and few gnathic cases have been tested for USP6 rearrangement. Rearrangements of CDH11 and/or USP6 are identified in approximately 70% of primary extragnathic ABCs. MATERIALS/METHODS Herein, this multi-institutional, IRB-approved study investigates the USP6 status and clinicopathologic characteristics of cases histopathologically diagnosed as primary gnathic ABC. This study retrospectively identified 11 cases from four Oral & Maxillofacial Pathology Services and submitted them for USP6 analysis. Evaluation of one case failed, but the results of FISH testing, histomorphology, patient age and sex, lesion location, lesion duration, and clinical impression were abstracted for the remaining 10 cases. Results The patients ranged in age from 10 to 43 years (mean: 25.4 years), with a male-to-female ratio of 1:1 (5:5). Nine cases occurred in the mandible and one case in the maxilla. The majority of lesions were present for an unknown duration or more than one month. Morphologically, five cases exhibited classic ABC features while five exhibited few cystic spaces with “solid” morphology. None of the tested cases demonstrated rearrangement of the USP6 locus by FISH. Conclusion In the jaws, lesions that morphologically mimic primary extragnathic ABC rarely show USP6 abnormalities, and may be genetically distinct lesions. Lesions with USP6 rearrangement are neoplastic; however, the etiology of lesions lacking rearrangement is less certain and may represent primary ABC without USP6 rearrangement, secondary ABC that have effaced the lesion of origin, or ABC-like degenerative lesions.

A multicentre study of oral paracoccidioidomycosis: Analysis of 320 cases and literature review.

To investigate the frequency of oral paracoccidioidomycosis from representative geographical regions of Brazil and to compare the data with a literature review. A retrospective study was conducted on 108,304 biopsies obtained from 1953 to 2016 at six Brazilian oral and maxillofacial pathology services. Demographic data and clinical and histopathological diagnosis of oral paracoccidioidomycosis were evaluated. A literature review of oral paracoccidioidomycosis studies published in three electronic databases was carried out. Data were analysed descriptively. A total of 320 cases of oral paracoccidioidomycosis were surveyed (0.3% of the oral lesions at the centres studied). The lesions were more frequent among male patients. The gingiva/alveolar ridge was the most affected site. Mean age of affected individuals was 51.3years (±11.7). The literature review showed a higher incidence of oral paracoccidioidomycosis in the south-east and south regions of Brazil. Male individuals and individuals between 50 and 59years were most affected. Oral paracoccidioidomycosis is an uncommon lesion observed in oral biopsy samples. The differences in the relative frequency of oral paracoccidioidomycosis are related to geographical variations. Men between 50 and 59years are more affected. This study provides helpful information for clinicians in the diagnosis of oral paracoccidioidomycosis.

The use of oral and maxillofacial pathology services by general pathologists and their attitude towards it in Saudi Arabia.

Objectives:To investigate the awareness and usage of oral and maxillofacial pathology (OMFP) subspecialty services among pathologists in Saudi Arabia.Methods:In this cross-sectional study, we conducted an electronic questionnaire survey of pathologists in all regions of Saudi Arabia. The study was conducted between July 2015 and August 2016. The questionnaire comprised 19 questions to evaluate the knowledge of pathologists regarding microscopic OMFP and their perceptions towards this subspecialty.Results:Most of the pathologists surveyed (94.6%) were aware of the OMFP subspecialty and its scope of practice. Although most of the pathologists recognized the importance and need of this subspecialty, 70% of them never referred or consulted an oral pathologist as they either diagnosed the cases themselves or did not know any oral pathologist (57.7%). The pathologists had the greatest difficulty in identifying and diagnosing odontogenic tumors, salivary gland tumors, and odontogenic cysts.Conclusion:Pathologists are aware of the OMFP subspecialty, but their utilization of the services offered by OMFP specialists in Saudi Arabia is quite low despite the strong demand for OMFP services.

Prevalence profile of odontogenic cysts and tumors on Brazilian sample after the reclassification of odontogenic keratocyst

PurposeThe aim of this study was to evaluate the impact of the reclassification of odontogenic keratocyst (OKC) as a tumor on the prevalence profile of odontogenic cysts (OCs) and odontogenic tumors (OTs). Study designTwo referral Oral and Maxillofacial Pathology services in Brazil were evaluated. All cases diagnosed as OCs or OTs were selected and classified according to the 1992 WHO-classification (cases before 2005 WHO classification of tumors excluding OKC) and the 2005 WHO classification of tumors, going forward including cases of odontogenic keratocyst tumor (KCOT). The frequency and prevalence of OCs and OTs were compared before and after the reclassification. ResultsAmong 27,854 oral biopsies, 4920 (17.66%) were OCs and 992 (3.56%) were OTs. The prevalence of OTs before 2005 WHO classification of tumors was 2.04%, while the prevalence after 2005 WHO classification was 11.51% (p < 0.0001). Before 2006, the most frequent tumor diagnosed was odontoma with 194 cases (39.67%), and after 2005 WHO classification of tumors the KCOT was the most frequent with 207 cases (41.07%). ConclusionsThe increase in the prevalence of OTs after 2005 WHO is related to the improvement of pathology services and to the inclusion of KCOT in the OTs group.