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Dentinogenic ghost cell tumor (DGCT) is an uncommon odontogenic tumor considered to be the solid, tumorous variant of calcifying odontogenic cyst. DGCT is characterized by islands of ameloblastoma-like epithelial cells that resemble the enamel organ, the presence of ghost cells, and dentinoid material. This article reports a rare case of dentinogenic ghost cell tumor as sociated with an odontoma in an adult patient, with a review of the literature. To the best of the authors' knowledge, there have only been four case reports of DGCT associated with odontoma, all of which occurred in children and adults younger than 30 years old. [ABSTRACT FROM AUTHOR]

Background/Purpose: This retrospective immunohistological pilot study aimed to investigate the influence of natural killer group 2, member D (NKG2D) ligand expression on ameloblastoma recurrence after surgical resection. It also aimed to elucidate additional clinical factors that could serve as predictors of ameloblastoma recurrence. Materials and methods: This study included 96 patients who were histologically diagnosed with ameloblastoma after surgical resection. The expression of NKG2D ligands, including UL16-binding proteins (ULBPs) 1–3 and major histocompatibility complex class I chain-related molecule (MIC) A/B, was evaluated in formalin-fixed paraffin-embedded tumor tissues via immunohistochemistry assays. Furthermore, the patients' electronic medical records were reviewed. Multivariate Cox regression analysis was conducted, and data were expressed as adjusted hazard ratios [HRs] with 95% confidence intervals [95% CIs]. Results: Multivariate analysis revealed that recurrent tumors (ref.: primary; adjusted HR [95% CI]: 2.780 [1.136, 6.803], p = 0.025) and positive MICA/B expression (ref.: negative; adjusted HR [95% CI]: 0.223 [0.050, 0.989], p = 0.048) independently affected recurrence-free survival in ameloblastoma. Conclusion: This study identified recurrent cases and loss of MICA/B expression as independent predictors of early ameloblastoma recurrence following surgical resection. The findings suggest that decreased MICA/B expression might undermine NKG2D-mediated tumor immunosurveillance, thereby influencing early recurrence. [ABSTRACT FROM AUTHOR]

Calcifying odontogenic cyst, also known as Gorlin cyst is a rare benign cystic lesion primarily found in the jawbones, accounting less than 1% of odontogenic cysts. It can be associated with odontogenic tumors such as odontomas. We report a rare case of COC associated with complex odontoma in a young patient and discuss its clinical features, diagnosis, and treatment options. An 18-year-old female patient presented with a painless radiopaque lesion of the right mandibular bone at Oral Medicine and Oral Surgery department. Radiographs revealed irregular tooth-like structures in the canine-premolar area. The lesion was surgically removed, and histopathology confirmed COC with a complex odontoma. As of the World Health Organization's 2022 definition, COC is a developmental odontogenic cyst characterized by calcified ghost cells. It typically affects individuals during their second and third decades of life, with no gender preference, almost equally in the maxilla and the mandible. The main treatment is total enucleation, with a generally favorable prognosis. Histopathology is essential for diagnosis due to its mimicry of other jaw conditions. Long-term follow-up is needed to prevent recurrences. [ABSTRACT FROM AUTHOR]

Targeted therapy has the potential to be used in the neoadjuvant setting for odontogenic tumors, reducing the morbidities associated with major surgery. In this regard, the aim of this study was to summarize the current evidence on the different forms of targeted therapy, effectiveness, and drawbacks of this course of treatment. Four databases were searched electronically without regard to publication date or language. Grey literature searches and manual searches were also undertaken. Publications with sufficient clinical data on targeted therapy for odontogenic tumors were required to meet the criteria for eligibility. The analysis of the data was descriptive. A total of 15 papers comprising 17 cases (15 ameloblastomas and 2 ameloblastic carcinomas) were included. Numerous mutations were found, with BRAF V600E being most common. Dabrafenib was the most utilized drug in targeted therapy. Except for one case, the treatment reduced the size of the lesion (16/17 cases), showing promise. Most of the adverse events recorded were mild, such as skin issues, voice changes, abnormal hair texture, dry eyes, and systemic symptoms (e.g., fatigue, joint pain, and nausea). It is possible to reach the conclusion that targeted therapy for ameloblastoma and ameloblastic carcinoma may be a useful treatment strategy, based on the findings of the included studies. [ABSTRACT FROM AUTHOR]

The article focuses on the detection of the BRAF V600E mutation in cell-free DNA (cfDNA) extracted from fluid aspirates of conventional ameloblastomas. It explores the potential of using liquid biopsy as a minimally invasive alternative to traditional tissue biopsies for diagnosing this mutation, which is prevalent in ameloblastomas and could significantly impact clinical management and treatment strategies.

The objective of this article is to report the clinical case and 4-year follow-up of a 5-year-old child with multiple dental anomalies, emphasizing the importance of early diagnosis and use of combined pediatric surgery and orthodontic approaches. A 5-year-old boy, accompanied by his mother, sought dental care for dental caries and tooth pain. Clinical and radiographic examinations revealed active caries, a supernumerary primary tooth in the region of the mandibular right second premolar, and severe ankylosis of the primary mandibular right second molar. The treatment plan involved extraction of the supernumerary tooth as well as sectioning and extraction of the ankylosed molar. When the patient was 6 years old, the permanent mandibular right first molar showed signs of an altered eruptive process, and orthodontic treatment was initiated. A unilateral band-and-loop space maintainer with coil springs designed to move the permanent first molar was placed on the primary first molar. A new panoramic radiograph, obtained when the patient was aged 7 years, suggested the presence of an odontoma in the apical region of the primary maxillary right canine. Surgical removal and histopathologic examination of the lesion confirmed that it was a developing odontoma. After surgery, due to occlusal anomalies that included transverse maxillary deficiency, deep overbite, and midline deviation, the patient underwent rapid maxillary expansion therapy with a Haas-type appliance. When the patient was 8 years old, orthodontic treatment continued with a removable palatal Hawley expander and a fixed mandibular lingual arch. Currently, at the age of 9 years, the child is still undergoing fixed orthodontic treatment after surgical exposure of the impacted permanent maxillary right canine and bonding of an orthodontic attachment to enable traction. A multidisciplinary approach to the management of dental anomalies promotes a favorable prognosis and ensures comprehensive treatment of young patients. [ABSTRACT FROM AUTHOR]

ABSTRACT Background Methods Results Conclusion Ameloblastoma is a locally destructive benign odontogenic tumor. While the neoplastic cells of conventional ameloblastoma can infiltrate the connective tissue and bone, in unicystic ameloblastoma the epithelium is encapsulated. The mechanisms driving ameloblastoma's bone resorption remains unclear.RNA sequencing (RNA‐seq) was performed in a discovery cohort of conventional ameloblastoma, and pathway enrichment analysis was carried out. mRNA levels of MMP13, a gene associated with bone resorption, were assessed using RT‐qPCR in a larger cohort of conventional ameloblastoma and in unicystic ameloblastoma. Zymogram gels and the immunoexpression profile of collagenase 3 (encoded by MMP13 gene) were evaluated as well.Enriched pathways related to bone mineralization and upregulation of MMP13 were observed in ameloblastomas. Collagenolytic activity of collagenase 3 was detected in the tumor lysates. Collagenase 3 immunopositivity was observed in ameloblastomatous epithelium infiltrating the fibrous capsule of unicystic ameloblastoma. At the tumor–bone interface, collagenase 3 expression was detected in stromal cells, osteoblasts, and osteocytes.The results indicate a potential involvement of MMP13 in ameloblastoma‐related bone resorption and progression. [ABSTRACT FROM AUTHOR]

Background: Podoplanin (PDPN) is a transmembrane glycoprotein implicated in the pathogenesis of odontogenic lesions (OL). It is localized at the membrane and cytoplasmic level, and its interaction with other proteins could trigger cell proliferation, invasion and migration. The main objective of this systematic review is to explore the immunoexpression pattern of podoplanin in OL. In addition, as secondary objectives, we aimed to compare the immunostaining intensity of PDPN in OL, to analyze its interaction networks by bioinformatic analysis and to highlight its importance as a potential diagnostic marker useful in the pathogenesis of OL. Methods: The protocol was developed following PRISMA and Cochrane guidelines. The digital search was performed in the databases: PubMed/MEDLINE, ScienceDirect, Scopus, Web of Science and Google Schoolar from August 15, 2010 to June 15, 2023. We included cross-sectional and cohort studies that will analyze the pattern of PDPN immunoexpression in OL. Two investigators independently searched for eligible articles, selected titles and abstracts, analyzed full text, conducted data collection, and performed assessment of study quality and risk of bias. In addition, part of the results were summarized through a random-effects meta-analysis. STRING database was used for protein-protein interaction analysis. Results: Twenty-nine relevant studies were included. The ages of the subjects ranged from 2 to 89 years, with a mean age of 33.41 years. Twenty-two point two percent were female, 21.4% were male, and in 56.4% the gender of the participants was not specified. A total of 1,337 OL samples were analyzed for PDPN immunoexpression pattern. Ninety-four (7.03%) were dental follicles and germs, 715 (53.47%) were odontogenic cysts, and 528 (39.49%) were odontogenic tumors. Meta-analysis indicated that the immunostaining intensity was significantly stronger in odontogenic keratocysts compared to dentigerous cysts (SMD=3.3(CI=1.85-4.82, p=0.000*). Furthermore, bioinformatic analysis revealed that PECAM-1, TNFRF10B, MSN, EZR and RDX interact directly with PDPN and their expression in OL was demonstrated. Conclusions: The results of the present systematic review support the unique immunoexpression of PDPN as a potential useful diagnostic marker in the pathogenesis of OL. [ABSTRACT FROM AUTHOR]

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Objective: This Bayesian network meta‐analysis was performed to analyze the associations between clinicopathological characteristics and BRAF mutations in ameloblastoma (AM) patients and to evaluate the diagnostic accuracy. Materials and Methods: Four electronic databases were searched from 2010 to 2024. The search terms used were specific to BRAF and AM. Observational studies or randomized controlled trials were considered eligible. The incidence of BRAF mutation and corresponding clinicopathological features in AM patients were subjected to Bayesian network analyses and diagnostic accuracy evaluation. Results: A total of 937 AM patients from 20 studies were included. The pooled prevalence of BRAF mutations in AM patients was 72%. According to the Bayesian network analysis, BRAF mutations are more likely to occur in younger (odds ratio [OR], 2.3; credible interval [CrI]: 1.2–4.5), mandible site (OR, 3.6; 95% CrI: 2.7–5.2), and unicystic (OR, 1.6; 95% CrI: 1.1–2.4) AM patients. Similarly, higher diagnostic accuracy was found in the younger, mandible, and unicystic AM groups. Conclusions: The incidence, risk, and diagnostic accuracy of BRAF mutation in AM were greater in younger patients, those with mandible involvement, and those with unicystic AM than in patients with other clinicopathological features. In addition, there was a strong concordance in the diagnostic accuracy between molecular tests and immunohistochemical analysis. [ABSTRACT FROM AUTHOR]

Background: The recent impact of artificial intelligence in diagnostic services has been enormous. Machine learning tools offer an innovative alternative to diagnose cysts and tumors radiographically that pose certain challenges due to the near similar presentation, anatomical variations, and superimposition. It is crucial that the performance of these models is evaluated for their clinical applicability in diagnosing cysts and tumors. Methods: A comprehensive literature search was carried out on eminent databases for published studies between January 2015 and December 2022. Studies utilizing machine learning models in the diagnosis of odontogenic cysts or tumors using Orthopantomograms (OPG) or Cone Beam Computed Tomographic images (CBCT) were included. QUADAS-2 tool was used for the assessment of the risk of bias and applicability concerns. Meta-analysis was performed for studies reporting sufficient performance metrics, separately for OPG and CBCT. Results: 16 studies were included for qualitative synthesis including a total of 10,872 odontogenic cysts and tumors. The sensitivity and specificity of machine learning in diagnosing cysts and tumors through OPG were 0.83 (95% CI 0.81–0.85) and 0.82 (95% CI 0.81–0.83) respectively. Studies utilizing CBCT noted a sensitivity of 0.88 (95% CI 0.87–0.88) and specificity of 0.88 (95% CI 0.87–0.89). Highest classification accuracy was 100%, noted for Support Vector Machine classifier. Conclusion: The results from the present review favoured machine learning models to be used as a clinical adjunct in the radiographic diagnosis of odontogenic cysts and tumors, provided they undergo robust training with a huge dataset. However, the arduous process, investment, and certain ethical concerns associated with the total dependence on technology must be taken into account. Standardized reporting of outcomes for diagnostic studies utilizing machine learning methods is recommended to ensure homogeneity in assessment criteria, facilitate comparison between different studies, and promote transparency in research findings. [ABSTRACT FROM AUTHOR]

Abstract Background Podoplanin (PDPN) is a transmembrane glycoprotein implicated in the pathogenesis of odontogenic lesions (OL). It is localized at the membrane and cytoplasmic level, and its interaction with other proteins could trigger cell proliferation, invasion and migration. The main objective of this systematic review is to explore the immunoexpression pattern of podoplanin in OL. In addition, as secondary objectives, we aimed to compare the immunostaining intensity of PDPN in OL, to analyze its interaction networks by bioinformatic analysis and to highlight its importance as a potential diagnostic marker useful in the pathogenesis of OL. Methods The protocol was developed following PRISMA and Cochrane guidelines. The digital search was performed in the databases: PubMed/MEDLINE, ScienceDirect, Scopus, Web of Science and Google Schoolar from August 15, 2010 to June 15, 2023. We included cross-sectional and cohort studies that will analyze the pattern of PDPN immunoexpression in OL. Two investigators independently searched for eligible articles, selected titles and abstracts, analyzed full text, conducted data collection, and performed assessment of study quality and risk of bias. In addition, part of the results were summarized through a random-effects meta-analysis. STRING database was used for protein-protein interaction analysis. Results Twenty-nine relevant studies were included. The ages of the subjects ranged from 2 to 89 years, with a mean age of 33.41 years. Twenty-two point two percent were female, 21.4% were male, and in 56.4% the gender of the participants was not specified. A total of 1,337 OL samples were analyzed for PDPN immunoexpression pattern. Ninety-four (7.03%) were dental follicles and germs, 715 (53.47%) were odontogenic cysts, and 528 (39.49%) were odontogenic tumors. Meta-analysis indicated that the immunostaining intensity was significantly stronger in odontogenic keratocysts compared to dentigerous cysts (SMD=3.3(CI=1.85-4.82, p=0.000*). Furthermore, bioinformatic analysis revealed that PECAM-1, TNFRF10B, MSN, EZR and RDX interact directly with PDPN and their expression in OL was demonstrated. Conclusions The results of the present systematic review support the unique immunoexpression of PDPN as a potential useful diagnostic marker in the pathogenesis of OL.

A dentinogenic ghost cell tumor (DGCT) is a rare benign odontogenic tumor that commonly shows characteristics of solid proliferation and has a relatively high risk of recurrence after surgical treatment. We herein report a case of a central DGCT that occurred in the maxilla and resulted in bone expansion. This study highlights new imaging findings (particularly magnetic resonance imaging) along with histopathological observations. In addition, we conducted a review of the existing literature on this rare tumor. A 37-year-old man developed swelling around the right cheek. A benign odontogenic tumor such as ameloblastoma was suspected based on the imaging examination findings (including bone expansion and the internal characteristics of the tumor) on panoramic imaging, computed tomography, and magnetic resonance imaging. The lesion was surgically excised from the right maxilla. Postoperative histopathological examination led to a definitive diagnosis of central DGCT. The tumor comprised epithelial neoplastic islands, resembling ameloblastoma, inside tight fibroconnective tissue; masses of ghost cells and formation of dentin were also observed. We had suspected that the minute high-density region around the molars on the imaging examinations represented alveolar bone change; however, it represented dentin formation. This led to difficulty diagnosing the lesion. Although DGCT may present characteristic findings on imaging examinations, its occurrence is infrequent, and in some cases, the findings may include the presence or absence of an impacted tooth without obvious calcification. The present case suggests that we should consider the possibility of an odontogenic tumor with calcification when high-density structures are observed inside the lesion. [ABSTRACT FROM AUTHOR]

Objective: The aim of this study is to determine the age-based prevalence of dens invaginatus cases and to learn the radiologic findings. In addition, fractal analysis of the periapical regions of unilateral dens invaginatus cases and contralateral teeth was performed to determine the effect of possible microleakage on fractal dimension. Methods: A total of 136 patients (170 teeth) identified in panoramic radiographs taken for diagnostic purposes between January 2018 and December 2023 at our Department of Oral and Maxillofacial Radiology were included in the study. Data were analysed using IBM SPSS V23. The Chi-square test was used for comparing categorical variables between groups. The relationship between the FD values calculated around the apexes of the teeth with unilateral dens invaginatus and the contralateral teeth was analyzed by paired t test. A significance level of p < 0.050 was adopted. Results: The mean age of the cases was calculated as 28.1 (8–63) years. 66 (48.5%) of the cases were female, and 70 (51.1%) were male. The lateral incisor was the most affected tooth among these cases. Bilateral cases were observed in 34 patients. Type 2 was detected in 93 patients, Type 1 in 35 patients, and Type 3 dens invagination in 8 patients. Dens invaginatus cases were observed in 134 maxillary and 2 mandibular teeth. Periapical lesions were seen in 22 of these cases. Conclusions: Dens invaginatus cases are a congenital anomaly encountered at any age. Early diagnosis is crucial to prevent the loss of pulp vitality due to these invaginations. It should be noted that these invaginations can affect both jaws. However, due to the prevalence of occurrence in the maxillary anterior teeth and asymptomatic nonvitality, particular attention should be paid to evaluating this region. [ABSTRACT FROM AUTHOR]

Cementoblastoma, a rare odontogenic benign tumor characterized by calcified cementum-like deposits produced by cementoblasts fused with the tooth root, represents a minute proportion of all odontogenic tumors, with a prevalence ranging from less than 1% to 6.2%. We present a case of a 19-year-old female experiencing pain, progressive swelling, and facial asymmetry in the left lower region over the 1 year ago. Physical examination revealed diffuse swelling in the left mandibular area, demonstrating tenderness and bony hardness on palpation. Radiographic findings displayed a giant, well-defined, relatively round, radiopaque mass, partially delineated by a thin radiolucent halo, and adhered to the roots of the teeth. Computed Tomography imaging revealed an osteoblastic hyperdense mass with extensive buccal and lingual extension. Sagittal images illustrated the mass's continuity with the root apex of the first molar, accompanied by a well-defined hypodense border. A biopsy confirmed the diagnosis of cementoblastoma, leading to the patient undergoing a left hemimandibulectomy. Given the various periapical radiopaque lesions that serve as potential differential diagnoses for cementoblastoma, the ability of the radiologist to distinguish their imaging characteristics plays a crucial role in determining an accurate diagnosis.

Background: Odontogenic carcinoma with dentinoid (OCD) is a rare and controversial entity, which has not yet been included in the current World Health Organization classification of odontogenic lesions. Owing to the small number of reported cases, the clinicopathological characteristics, biological behavior, prognosis, and appropriate treatment strategies for OCD remain to be defined. Herein, we present an additional case of OCD with a focus on the differential diagnosis and review of the pertinent literature, in order to enable better recognition by oral clinicians and pathologists and further characterization of this entity. Case presentation: This paper reports a case of OCD in the posterior mandible of a 22-year-old female. Radiography showed a well-defined unilocular radiolucency with radiopaque materials. The intraoperative frozen section pathology gave a non-committed diagnosis of odontogenic neoplasm with uncertain malignant potential. Then a partial mandibulectomy with free iliac crest bone graft and titanium implants was performed. Microscopically, the tumor consisted of sheets, islands, and cords of round to polygonal epithelial cells associated with an abundant dentinoid matrix. Immunohistochemically, the tumor cells were diffusely positive for CK19, p63, and β-catenin (cytoplasmic and nuclear). No rearrangement of the EWSR1 gene was detected. The final diagnosis was OCD. There has been no evidence of recurrence or metastasis for 58 months after surgery. We also provide a literature review of OCD cases, including one case previously reported as ghost cell odontogenic carcinoma from our hospital. Conclusions: OCD is a locally aggressive low grade malignancy without apparent metastatic potential. Wide surgical excision with clear margins and long-term period follow-up to identify any possible recurrence or metastases are recommended. Histopathological examination is essential to conclude the diagnosis. Special care must be taken to distinguish OCD from ghost cell odontogenic carcinoma and clear cell odontogenic carcinoma, as misdiagnosis might lead to unnecessary overtreatment. Study of additional cases is required to further characterize the clinicopathological features and clarify the nosologic status and biological behavior of this tumor. [ABSTRACT FROM AUTHOR]

In the 2022, World Health Organisation classification of odontogenic tumours, the clear cell odontogenic carcinoma is designated as a malignant odontogenic tumour with high recurrence and aggressive behaviour. Deceptive behaviour in the context of a wide range of differentials presents a significant diagnostic problem. It is the fifth most commom type of malignant odontogenic tumor. A systematic assessment of published cases, case series, and retrospective investigations of diagnostic significance of EWSR1 gene in clear cell odontogenic carcinoma is presented to determine trends in presentation, diagnostic characteristics, treatment, and patient outcome. To locate papers reporting clear cell odontogenic carcinoma and EWSR1, extensive database searches were carried out. Demographics, tumour location, immunohistochemical and molecular tests, treatment, follow-up, and recurrence were the variables. 34 cases were detected; 52.9% (n = 18) of the cases were females. The average age was 62.5 years, with a range of 43–82 years. The average size ranged from 3.4 to 8 cm. The mandibular body was the most common location, followed by the maxilla. Maximum immunohistochemistry positivity revealed by CK 19, CKAE1/3, EMA and p63. Most common gene fusion detected was EWSR1-ATF1 in 62.4% of cases contributing to its diagnostic attributes. Surgical treatment was used in 97% of cases. The average follow-up period was 30.3 months, and recurrence was reported in 52.4% of the cases. CCOC can metastasize, and the prognosis is fair. This is first systematic review, where we have attempted to consolidate the mutational expression of EWSR1 in Clear cell odontogenic carcinoma. It is difficult to identify from other clear cell tumours of the head and neck region. It is crucial to distinguish it from other clear cell lesions because of its aggressiveness. [ABSTRACT FROM AUTHOR]

Odontogenic bone tumor (OT) is a rare pathology in the world, but it is very common in developing countries; its etiology is still unknown, and it causes serious deformities of the mandible and maxilla if it is not operated upon soon. Lassa virus (LASV) belongs to the Arenaviridae family, and its reservoir is a rodent of the genus Mastomys. The transmission of the LASV to humans can occur through ingestion or inhalation by contact with dirty objects, the consumption of contaminated food, or exposure to wounds, as rodents shed the virus in their urine and excrement. In this observational study, we aim to evaluate the presence of LASV in OT patient tissues collected in the Democratic Republic of the Congo. For this purpose, a group of nine patients affected by OT were enrolled, and the tissues derived from the surgery were collected. In total, 81.5% of the tissues were positive for LASV presence. Interestingly, we found that not only was the tumor LASV-positive, but in some cases, the bone was close to the tumor and the oral mucosa lining. These preliminary data could suggest the hypothesis that LASV may be involved with the onset of OT. [ABSTRACT FROM AUTHOR]

Ameloblastic fibrodentinoma (AFD) is a rare benign odontogenic tumor that resembles an ameloblastic fibroma with dysplastic dentin. This report presents a rare case of mandibular AFD with imaging features in a young patient. Panoramic radiography and computed tomography revealed a well-defined lesion with internal septa and calcified foci, causing inferior displacement of the adjacent molars as well as buccolingual cortical thinning and expansion of the posterior mandible. The lesion was surgically removed via mass excision, and the involved tooth was extracted under general anesthesia. During the 5-year follow-up period, no evidence of recurrence was observed. Radiologic features of AFD typically reveal a moderately to well-defined mixed lesion with varying degrees of radiopacity, reflecting the extent of dentin formation. Radiologists should consider AFD in the differential diagnosis when encountering a multilocular lesion with little dense radiopacity, particularly if it is associated with delayed eruption, impaction, or absence of involved teeth, on radiographic images of young patients. [ABSTRACT FROM AUTHOR]

Periodontitis is linked to the onset and progression of oral squamous cell carcinoma (OSCC), an epidemiologically frequent and clinically aggressive malignancy. In this context, Fusobacterium (F.) nucleatum and Porphyromonas (P.) gingivalis, two bacteria that cause periodontitis, are found in OSCC tissues as well as in oral premalignant lesions, where they exert pro-tumorigenic activities. Since the two bacteria are present also in endodontic diseases, playing a role in their pathogenesis, here we analyze the literature searching for information on the impact that endodontic infection by P. gingivalis or F. nucleatum could have on cellular and molecular events involved in oral carcinogenesis. Results from the reviewed papers indicate that infection by P. gingivalis and/or F. nucleatum triggers the production of inflammatory cytokines and growth factors in dental pulp cells or periodontal cells, affecting the survival, proliferation, invasion, and differentiation of OSCC cells. In addition, the two bacteria and the cytokines they induce halt the differentiation and stimulate the proliferation and invasion of stem cells populating the dental pulp or the periodontium. Although most of the literature confutes the possibility that bacteria-induced endodontic inflammatory diseases could impact on oral carcinogenesis, the papers we have analyzed and discussed herein recommend further investigations on this topic. [ABSTRACT FROM AUTHOR]

Background: Odontogenic lesions constitute a heterogeneous group of lesions. CLIC4 protein regulates different cellular processes, including epithelial-mesenchymal transition and fibroblast-myofibroblast transdifferentiation. This study analyzed CLIC4, E-cadherin, Vimentin, and α-SMA immunoexpression in epithelial odontogenic lesions that exhibit different biological behavior. Methods: It analyzed the immunoexpression of CLIC4, E-cadherin, and Vimentin in the epithelial cells, as well as CLIC4 and α-SMA in the mesenchymal cells, of ameloblastoma (AM) (n = 16), odontogenic keratocyst (OKC) (n = 20), and adenomatoid odontogenic tumor (AOT) (n = 8). Immunoexpressions were categorized as score 0 (0% positive cells), 1 (< 25%), 2 (≥ 25% - < 50%), 3 (≥ 50% - < 75%), or 4 (≥ 75%). Results: Cytoplasmic CLIC4 immunoexpression was higher in AM and AOT (p < 0.001) epithelial cells. Nuclear-cytoplasmic CLIC4 was higher in OKC's epithelial lining (p < 0.001). Membrane (p = 0.012) and membrane-cytoplasmic (p < 0.001) E-cadherin immunoexpression were higher in OKC, while cytoplasmic E-cadherin expression was higher in AM and AOT (p < 0.001). Vimentin immunoexpression was higher in AM and AOT (p < 0.001). Stromal CLIC4 was higher in AM and OKC (p = 0.008). Similarly, α-SMA immunoexpression was higher in AM and OKC (p = 0.037). Correlations in these proteins' immunoexpression were observed in AM and OKC (p < 0.05). Conclusions: CLIC4 seems to regulate the epithelial-mesenchymal transition, modifying E-cadherin and Vimentin expression. In mesenchymal cells, CLIC4 may play a role in fibroblast-myofibroblast transdifferentiation. CLIC4 may be associated with epithelial odontogenic lesions with aggressive biological behavior. [ABSTRACT FROM AUTHOR]

Odontogenic tumors (OTs) are distinct conditions that develop in the jawbones, exhibiting diverse histopathological features and variable clinical behaviors. Unfortunately, the literature on this subject in Saudi Arabia remains sparse, indicating a pressing need for more comprehensive data concerning the frequency, demographics, treatment modalities, and outcomes of OTs. Objectives: The study aims to evaluate the frequency, demographic features, treatment, and outcomes of OTs across three tertiary medical centers. Methods and Material: OT cases were identified in King Abdulaziz Medical City (KAMC), King Fahad Medical City (KFMC), and Prince Sultan Military Medical City (PSMMC) from January 2010 to December 2021. Results: Ninety-two OT cases were identified from the anatomical pathology laboratories of three tertiary hospitals. KFMC contributed the highest number of cases (43.5%), followed by KAMC (30.4%) and PSMMC (26.1%). The median age of OT patients was 29 years (range: 5–83), with males representing more than half of the patients (56.5%). The mandible was the most frequent site of OT occurrence (72.5%), with ameloblastoma being the predominant OT (63.0%), followed by odontoma (19.5%). Among the treatment modalities, bone resection was employed the most (51.0%), followed by enucleation (25.6%). Notably, 11.5% of OT cases with available follow-up data exhibited recurrence, with ameloblastoma accounting for eight recurrent cases. Conclusions: Although OTs are relatively common in the jaws, they are rare in anatomical pathology laboratories and the general population. This study contributes valuable insights into the epidemiology characteristics, treatment trends, and recurrence rates of OTs in Saudi Arabia. [ABSTRACT FROM AUTHOR]

The article presents a case study of a 1-year-old feline with maxillary mass in a 1-year-old feline, with topics including the history of the mass, clinical and gross findings, and diagnostic imaging findings. The history includes the excision of the mass three years prior, followed by progressive swelling, dysphagia, and epiphora. Transgingival fine needle aspirate showed blood and mild mixed inflammation.

Adenoid ameloblastoma with dentinoid had been perceived as a rare odontogenic tumor with bridging histopathological features between ameloblastoma and adenomatoid odontogenic tumor. Due to the mixture of histopathological features of two separate and well-recognized entities, adenoid ameloblastoma was also regarded as a hybrid lesion. The diversity in the histopathological presentation among the cases has disaccorded the nature, behaviour, and prognosis of this pathology. Despite the literature acknowledging the histopathological diversity, categorizing all these variations into one and addressing them as a single entity was lagging till the 5th edition of the odontogenic tumor classification by the WHO was forwarded. With the establishment of the new terminology of adenoid ameloblastoma and the enlistment of its diagnostic criteria, the scientific literature has advocated updating, contributing, and redefining the various aspects of this pathology. Here, we present a case of a 34-year-old male who presented with a chief complaint of swelling in the lower front region of his jaw in the past one month. The swelling was associated with pain that was sudden in onset with a progressive increase in size. The swelling was also associated with discharge that resembled pus. A panoramic radiograph showed a mixed radiopaque and radiolucent area, extending from the distal aspect of 32 up to the distal aspect of 43. The entire cystic lining along with the growth was excised and sent for histopathological examination. Correlating clinically, the histopathological features are suggestive of adenoid ameloblastoma. Scientific literature has stood as a boon to evidence-based practice. The diagnosis for the present case report is truly an outcome of the literature-based update which helped the diagnosis of the case as a separate entity rather than as a hybrid pathology. The goal was to enhance the understanding of the lesions in terms of their clinical characteristics and diverse histopathological morphology. [ABSTRACT FROM AUTHOR]

Ameloblastoma in dogs most often has a highly conserved acanthomatous cell morphology and is recognized as canine acanthomatous ameloblastoma (CAA) while conventional ameloblastoma (CA) makes up a smaller yet morphologically diverse group of epithelial odontogenic tumors. In humans, a rare desmoplastic histological subtype has distinctive clinical, radiological, and microscopic features. Desmoplastic ameloblastoma (DA) has not previously been described in dogs, although it has been rarely referenced in the veterinary literature. This is the first thorough description of a case series of DA in dogs and describes clinical presentation, diagnostic imaging findings, histopathological features for diagnosis, and treatment outcome. Clinically, DA most often presents as a mass or swelling in the rostral mandible or maxilla of middle age to older dogs. On diagnostic imaging, the lesion has a radiolucent or mixed pattern with well-defined borders and variable loculation. As a solid, fibrous tumor with obscured odontogenic epithelium, DA is challenging to diagnose histologically and can mimic several other oral tumors, both benign and malignant. As an ameloblastoma, the biological behavior of DA is locally destructive yet benign and prognosis is favorable following surgical excision. [ABSTRACT FROM AUTHOR]

Background: Ghost cell odontogenic carcinoma (GCOC) is a rare malignancy characterized by the presence of ghost cells, preferably in the maxilla. Only slightly more than 50 case reports of GCOC have been documented to date. Due to the rarity of this tumor and its nonspecific clinical criteria, there is a heightened risk of misdiagnosis in clinical examination, imaging findings, and pathology interpretation. Case presentation: A 50-year-old male patient presented to the hospital due to experiencing pain in his lower front teeth while eating for the past 2 months. Upon examination, a red, hard, painless mass was found in his left lower jaw, measuring approximately 4.0 cm × 3.5 cm. Based on the malignant histological morphology of the tumor and the abundant red-stained keratinized material, the preoperative frozen section pathology misdiagnosed it as squamous cell carcinoma (SCC). The surgical resection specimen pathology via paraffin section revealed that the tumor was characterized by round-like epithelial islands within the fibrous interstitium, accompanied by a large number of ghost cells and some dysplastic dentin with infiltrative growth. The malignant components displayed marked heterogeneity and mitotic activity. Additionally, a calcified cystic tumor component of odontogenic origin was observed. Hemorrhage, necrosis, and calcifications were present, with a foreign body reaction around ghost cells. Immunoreactivity for β-catenin showed strong nuclear positivity in tumor cells, while immunostaining was completely negative for p53. The Ki67 proliferation index was approximately 30–40%. The tumor cells exhibited diffuse CK5/6, p63, and p40 immunoreactivity, with varying immunopositivity for EMA. Furthermore, no BRAFV600E mutation was identified by ARMS-PCR. The final pathology confirmed that the tumor was a mandible GCOC. Conclusion: We have reported and summarized for the first time the specific manifestations of GCOC in frozen section pathology and possible pitfalls in misdiagnosis. We also reviewed and summarized the etiology, pathological features, molecular characteristics, differential diagnosis, imaging features, and current main treatment options for GCOC. Due to its rarity, the diagnosis and treatment of this disease still face certain challenges. A correct understanding of the pathological morphology of GCOC, distinguishing the ghost cells and the secondary stromal reaction around them, is crucial for reducing misdiagnosis rates. [ABSTRACT FROM AUTHOR]

Background: Cementoblastoma is a rare odontogenic tumor characterized by the formation of osteocementum-like tissue on a tooth root directly by neoplastic cementoblasts. Although it is categorized as benign, it has a high potential for growth with a certain degree of recurrence risk. However, there are only a few studies describing the features of recurrent cementoblastoma. The diagnosis of recurrent cementoblastoma is challenging not only due to its cytological atypia but also because of its large size and multicentric growth pattern. These characteristics suggest a potential for malignancy. Case presentation: A 29-year-old woman was transferred to our university dental hospital complaining of swelling of the right mandible. She had a history of enucleation of cementoblastoma associated with the third molar of the right mandible. Five years after the initial treatment, imaging demonstrated well-circumscribed multicentric radiopaque lesions in the same area. Histologically, the lesion consisted of osteocementum-like tissue rimmed with polygonal or plump tumor cells. Several cells were large epithelioid cells with bizarre nucleoli, which may be reminiscent of malignant tumors. Otherwise, there were no apparent malignant findings, including proliferative activity or atypical mitotic figure. Besides, tumor cells were positive for c-FOS, a marker of osteoblastoma and cementoblastoma. Eventually, the patient was diagnosed with recurrent cementoblastoma. Conclusions: Pathological analyses of this case suggested that the recurrent event in the cementoblastoma altered its growth pattern and tumor cell shape. Moreover, in the case of enucleation surgery, long-term follow-up is important because there is some recurrent risk of cementoblastoma, although it is not high. [ABSTRACT FROM AUTHOR]

Background: Radiolucencies found at the root apex in patients with cemento-osseous dysplasia (COD) may be mistaken for periapical cysts (PC) of endodontic origin. The purpose of this study was to examine the utility of quantitative texture analysis using cone-beam computed tomography (CBCT) to differentiate between COD and PC. Methods: Patients who underwent CBCT at Wonkwang University Daejeon Dental Hospital between January 2019 and December 2022 and were diagnosed with COD and PC by clinical, radiologic, and, if necessary, histopathologic examination were included. Twenty-five patients each were retrospectively enrolled in the COD and PC group. All lesions observed on axial CBCT images were manually segmented using the open-access software MaZda version 4.6 to establish the regions of interest, which were then subjected to texture analysis. Among the 279 texture features obtained, 10 texture features with the highest Fisher coefficients were selected. Statistical analysis was performed using the Mann-Whitney U-test, Welch's t-test, or Student's t-test. Texture features that showed significant differences were subjected to receiver operating characteristics (ROC) curve analysis to evaluate the differential diagnostic ability of COD and PC. Results: The COD group consisted of 22 men and 3 women, while the PC group consisted of 14 men and 11 women, showing a significant difference between the two groups in terms of sex (p=0.003). The 10 selected texture features belonged to the gray level co-occurrence matrix and included the sum of average, sum of entropy, entropy, and difference of entropy. All 10 selected texture features showed statistically significant differences (p<0.05) when comparing patients with COD (n=25) versus those with PC (n=25), osteolytic-stage COD (n=11) versus PC (n=25), and osteolytic-stage COD (n=11) versus cementoblastic-stage COD (n=14). ROC curve analysis to determine the ability to differentiate between COD and PC showed a high area under the curve ranging from 0.96 to 0.98. Conclusion: Texture analysis of CBCT images has shown good diagnostic value in the differential diagnosis of COD and PC, which can help prevent unnecessary endodontic treatment, invasive biopsy, or surgical intervention associated with increased risk of infection. [ABSTRACT FROM AUTHOR]

Background: Odontogenic cysts/tumor can cause severe bone destruction, which affects maxillofacial function and aesthetics. Meanwhile, metabolic reprogramming is an important hallmark of diseases. Changes in metabolic flow affect all aspects of disease, especially bone-related diseases. At present, the researches on pathogenesis of odontogenic cysts/tumor are mainly focused on the level of gene regulation, but the effects of metabolic alterations on odontogenic cysts/tumor have still underexplored. Materials and methods: Imaging analysis was used to evaluate the lesion size of different odontogenic lesions. Tartrate resistant acid phosphatase (TRAP) and immunohistochemistry (IHC) assays were utilized to detect the differences in bone destruction activity in odontogenic cysts and tumors. Furthermore, metabolomics and weighted gene co-expression network analysis (WGCNA) were conducted for the metabolomic features and key metabolite screening, respectively. The effect of ferroptosis inhibition on bone destruction was confirmed by IHC, immunofluorescence, and malondialdehyde colorimetric assay. Results: The bone destruction activity of ameloblastoma (AM) was the strongest and the weakest in odontogenic cysts (OC). High-throughput targeted metabolomics was used to map the metabolomic profiles of OC, odontogenic keratocyst (OKC) and AM. WGCNA and differential analysis identified L-cysteine in OKC and AM. Cystathionine γ-lyase (CTH) was further screened by Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis. The functions of L-cysteine were further validated. Finally, we confirmed that CTH affected destructive activities by regulating the sensitivity of epithelial cells to ferroptosis. Conclusion: High-throughput targeted metabolomics performed on diseased tissue confirmed the unique alteration of metabolic profiles in OKC and AM. CTH and its metabolite L-cysteine are the key factors regulating destructive activities. [ABSTRACT FROM AUTHOR]

Ameloblastic carcinoma is a rare malignant odontogenic tumor that is further classified into being primary or secondary arising from a preexisting benign ameloblastoma. It affects the mandible in two thirds of the patients. There is no standard treatment protocol for this lesion but radicalsurgical excision with or without radiotherapy is reported in the majority of cases. In this paper, we present a case of a 22 year old male diagnosed with Ameloblastic carcinoma of the mandible with a clinical course of typical aggressiveness and extensive destruction. Histopathological examination of the incised biopsy showed a parakeratinized stratified squamous epithelium with underlying fibrous connective tissue stroma. The stroma is highly myxomatous and exhibits islands of odontogenic epithelium and chronic inflammatory cell infiltrates. Interlacing strands of odontogenic epithelium shows stellate reticulum-like cells and occasional areas of squamous metaplasia with cellular and nuclear pleomorphism. In addition, mitotic figures were noted. With the correlation of clinical, radiographic, and histological features, the lesion is diagnosed as ameloblastic carcinoma. The lesion was surgical excised and post-treatment follow-up for 6 months revealed no recurrence of the malignancy. [ABSTRACT FROM AUTHOR]

The jaws are complicated structures in anatomy that house many different tissues. Embedded within these tissues lie the remains of tooth development that sometimes results in pathological conditions. Odontogenic tumors with benign epithelial characterizations constitute a particular group developing from cells of epithelium involved in tooth formation. Although being usually slow growing and non-aggressive, these lesions could be associated with considerable problems due to their location or capacity for expansion. This article explores the clinical challenges associated with diagnosing benign epithelial odontogenic tumors. Also, this paper looks into the specificities of four most common types such as ameloblastoma, adenomatoid odontogenic tumor, squamous odontogenic tumour and calcifying epithelial odontogenic tumour. The characteristic signs, symptoms and radiographic presentations as well as histological profiles at each type may enable clinicians to improve their diagnostic accuracy leading to appropriate management directions. Therefore, it is important to intervene early before complications occur so as to ensure favorable patient outcomes from this ailment that can manifest either on soft or even hard tissue surfaces. [ABSTRACT FROM AUTHOR]

The prevalence of intra-osseous jaw lesions differs in various populations; it remains a major concern for dentists and oral surgeons. Jawbones can be afflicted by a varied group of lesions and can present in diverse clinical patterns, hence adequate knowledge of the clinical and demographic characteristics of these lesions is necessary for the early detection and management. Hence, this study was designed to analyze the prevalence of intra-osseous jaw lesions in the pediatric population. The histopathology reports of all oral jaw lesions from the pediatric population, aged 0-14 years, between 1991 to 2023 period were retrospectively analyzed from the archives of the Department of our Institute and the data were analyzed through descriptive statistics. Our investigation underscores a predominance of intraosseous jaw lesions among males (53%) compared to females (47%), with the most commonly affected age group falling within the range of 6 to 11 years. The posterior mandible emerged as the primary location of these lesions, followed closely by the posterior maxilla. The histopathological examination further elucidates the landscape of these lesions, with radicular cysts comprising the majority (36%), trailed by dentigerous cysts (23%), odontogenic tumors (20%), and various other entities such as reactive/inflammatory (9%), fibro-osseous (7%), and neoplastic lesions (4%). In light of these findings, dental practitioners and specialists must have a complete understanding of the clinical and demographic characteristics associated with intraosseous jaw lesions in pediatric patients. Early recognition and accurate diagnosis are paramount for effective management and optimal patient outcomes. [ABSTRACT FROM AUTHOR]

The current case report aims to document a rare presentation of a distant odontogenic lesion of a 35-year-old male patient with mild clinical discomfort in the mandibular right first molar; exploring the diagnostic and therapeutic intricacies of an uncommon distant endodontic pathosis ultimately resolved through meticulous nonsurgical retreatment. Despite a normal oral examination, diagnostic radiography revealed a suboptimal root canal treatment and apical lesions surrounding mesial- and distal-root apices; including a distinct radiolucency beneath the apex of the second mandibular molar discovered through panoramic radiography, and confirmed via cone-beam computed tomography. In addition, the computed tomography disclosed a previously unreported and unusually large endodontic lesion that extended toward the mandibular canal; highlighting a necessity for the continued exploration of a unique endodontic presentation. A nonsurgical endodontic retreatment led to a remarkable reduction in the radiolucent lesions within one year; emphasizing the significance of comprehensive diagnostic approaches and individualized treatments. [ABSTRACT FROM AUTHOR]

Dentinogenic ghost cell tumor (DGCT) is a rare benign neoplasm form of calcifying odontogenic cyst (COC) characterized by ghost cells. Although benign, it presents an aggressive behavior. DGCT accounts for 2% to 14% of all COCs and less than 0.5% of all odontogenic tumors. It is a benign odontogenic tumor despite its local invasion and the likelihood of recurrence. To detect recurrence, central DGCT patients must be monitored long-term. We present the case of a 51-year-old male who reported pain in the right upper back tooth region. On examination, a soft to firm, bright red swelling was present in the buccal vestibule and gingival margin of the maxillary right first and second molar, which extended up to the palate. Histopathological analysis confirmed the diagnosis of a DGCT, which occurred in a previously treated calcifying odontogenic cyst. The case is reported here, along with a review of the literature update of such recurred instances in the past.

Background: Ameloblastomas are a rare type of benign neoplastic tumors that are locally invasive and make up around 1% of all head-and-neck tumors. Mostly diagnosed in people between the ages of 30 and 60 years, it has a global incidence of about 0.5% of cases per million person years. Ameloblastomas are classified as multicystic, unicystic, peripheral, and desmoplastic variants. Unicystic ameloblastomas (UAs), accounting for about 6% of the cases, have a high recurrence rate. It is histologically divided into luminal, intraluminal, and mural types. As the mural variant is aggressive and has the highest chance of recurrence, radical resection of tumor is required. Case Presentation: A case of 47-year-old patient, diagnosed as unicystic mural variant of ameloblastoma presented to us in March 2023 at the department of head-and-neck surgery at a tertiary care setup in Karachi, Pakistan. Postoperatively, the patient is now on 6-month follow-up with no residual or recurrence report as of yet. Conclusion: We report a rare case of UA mural variant in the right mandible, which highlights the importance of prompt diagnosis and treatment of this type of ameloblastoma, particularly in a location where they can cause significant damage. [ABSTRACT FROM AUTHOR]

The article describes the case of nasopharyngeal choristoma with features consistent with hairy cell polyp and compound odontoma arising from the skull base in a premature newborn. Topics discussed include prenatal diagnosis of a cleft palate, complication of the pregnancy, and finding on surgical pathology.

The article presents a case of adenomatoid odontogenic tumor (AOT) in a 13-year-old patient and its differential diagnosis, focusing on calcifying odontogenic cyst (COC), cemento-ossifying fibroma (COF), and focal cemento-osseous dysplasia (FocCOD). Topics discussed include the clinical and radiographic features distinguishing these lesions, their histopathologic characteristics, and the treatment and prognosis for AOT.

Abstract Background Odontogenic tumors a variety of benign and malignant lesions developed exclusively in the jaws. They are known to have variable clinical behaviors and different histological features. The development of odontogenic tumors is attributed to alterations in some genetic and biological molecules. The aim of this study is to assess Glypican-3 immune expression in different groups of odontogenic neoplasms as in Ameloblastoma, Ameloblastic Fibroma, and Ameloblastic Carcinoma, and compare it to dental follicle tissue as control group. Also correlate the marker expression with the known biological behavior of these tumors. This study included 40 cases were selected from oral and maxillofacial pathology department (ten cases in each group). Some sections are prepared to be stained with H&E stain and other sections with Glypican-3 immune stain. Histological examination and Histomorphometric analysis were done finally under light microscope. The area percents of Glypican-3 immune expression in all tumor sections were measured. Results Level of expression of Glypican-3 revealed significant difference between the study groups (P-value

Background Various stemness markers (SOX2, OCT4, and NANOG) have been studied in odontogenic cysts and tumors. However, studies on SALL4 having similar properties of stemness has not been documented. Additionally, insight into fascin as a migratory molecule is less explored. In this study, the expression of SALL4 and fascin were evaluated in ameloblastoma, adenomatoid odontogenic tumor (AOT), odontogenic keratocyst (OKC), dentigerous cyst (DC), radicular cyst (RC), and calcifying odontogenic cyst (COC). Methods Semi-quantitative analysis of fascin and SALL4 immuno-positive cells was done in a total of 40 cases of ameloblastoma (11 plexiform, 12 follicular, 12 unicystic, and 5 desmoplastic) variants, 6 cases of AOT, 15 each of OKC, DC, RC and 5 of COC. Chi-square test was applied to evaluate the association between SALL4 and fascin expression in odontogenic cysts and tumors. Results Fascin immunopositivity was observed in peripheral ameloblast-like cells, and the expression was weak or absent in stellate reticulum-like cells. A moderate to weak immune-reactivity to SALL4 was observed in the cytoplasm of ameloblastoma, epithelial cells of dentigerous and radicular cysts, having a marked inflammatory infiltrate, which was an interesting observation. COC and AOT had negative to weak expressions. No recurrence has been reported. Conclusions Expression of fascin in ameloblastomas elucidate their role in motility and localized invasion. Its expression in less aggressive lesions like DC, COC, AOT will incite to explore the other functional properties of fascin. SALL4 expression in the cytoplasm of odontogenic cysts and tumors may represent inactive or mutant forms which requires further validation.

Background Various stemness markers (SOX2, OCT4, and NANOG) have been studied in odontogenic cysts and tumors. However, studies on SALL4 having similar properties of stemness has not been documented. Additionally, insight into fascin as a migratory molecule is less explored. In this study, the expression of SALL4 and fascin were evaluated in ameloblastoma, adenomatoid odontogenic tumor (AOT), odontogenic keratocyst (OKC), dentigerous cyst (DC), radicular cyst (RC), and calcifying odontogenic cyst (COC). Methods Semi-quantitative analysis of fascin and SALL4 immuno-positive cells was done in a total of 40 cases of ameloblastoma (11 plexiform, 12 follicular, 12 unicystic, and 5 desmoplastic) variants, 6 cases of AOT, 15 each of OKC, DC, RC and 5 of COC. Chi-square test was applied to evaluate the association between SALL4 and fascin expression in odontogenic cysts and tumors. Results Fascin immunopositivity was observed in peripheral ameloblast-like cells, and the expression was weak or absent in stellate reticulum-like cells. A moderate to weak immune-reactivity to SALL4 was observed in the cytoplasm of ameloblastoma, epithelial cells of dentigerous and radicular cysts, having a marked inflammatory infiltrate, which was an interesting observation. COC and AOT had negative to weak expressions. No recurrence has been reported. Conclusions Expression of fascin in ameloblastomas elucidate their role in motility and localized invasion. Its expression in less aggressive lesions like DC, COC, AOT will incite to explore the other functional properties of fascin. SALL4 expression in the cytoplasm of odontogenic cysts and tumors may represent inactive or mutant forms which requires further validation.

Background: Odontogenic tumors a variety of benign and malignant lesions developed exclusively in the jaws. They are known to have variable clinical behaviors and different histological features. The development of odontogenic tumors is attributed to alterations in some genetic and biological molecules. The aim of this study is to assess Glypican-3 immune expression in different groups of odontogenic neoplasms as in Ameloblastoma, Ameloblastic Fibroma, and Ameloblastic Carcinoma, and compare it to dental follicle tissue as control group. Also correlate the marker expression with the known biological behavior of these tumors. This study included 40 cases were selected from oral and maxillofacial pathology department (ten cases in each group). Some sections are prepared to be stained with H&E stain and other sections with Glypican-3 immune stain. Histological examination and Histomorphometric analysis were done finally under light microscope. The area percents of Glypican-3 immune expression in all tumor sections were measured. Results: Level of expression of Glypican-3 revealed significant difference between the study groups (P-value < or = 0.05). The level of immune expression was highest in ameloblastic carcinoma group (M = 58.7) followed by ameloblastoma group (M = 33.9), then ameloblastic fibroma (M = 5.6) and lowest in the control group of dental follicle (M = 1.3). Conclusions: Glypican-3 immune expression demonstrated statistically significant difference among the study groups, indicating that it may have contributing role in tumor pathogenesis and its biological behavior. [ABSTRACT FROM AUTHOR]

Hybrid odontogenic tumors are characterized by presenting histopathological features of two or more distinct odontogenic lesions. Here we report a hybrid odontogenic tumor case composed of an ameloblastoma (AM) recurrence associated with ameloblastic fibroma (AF). A 60-year-old male patient underwent a clinical follow-up of an AM surgically treated 10 years ago. The computed tomography scan identified an isodense osteolytic lesion partially obliterating the left maxillary sinus. Due to the medical history, the clinical hypothesis was AM recurrence. Microscopic examination revealed a benign odontogenic neoplasm showing areas of ameloblastomatous epithelium proliferation in a dense connective tissue stroma and areas of ameloblastic epithelium with a myxoid cell-rich connective tissue. The final diagnosis was AM associated with AF. Hybrid odontogenic lesions are widely discussed, and an accurate microscopic examination is essential to determine their clinical behavior. Due to its sporadic reports, long-term follow-ups are necessary to better understand their prognosis. [ABSTRACT FROM AUTHOR]

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Odontogenic tumors represent a collection of entities ranging from hamartomas to destructive benign and malignant neoplasms. Occasionally, pathologists encounter gnathic lesions which clearly exhibit an odontogenic origin but do not fit within the confines of established diagnoses. Here, we describe two such odontogenic tumors, both affecting 3-year-old males. Each case presented as a destructive, radiolucent mandibular lesion composed of mesenchymal cells, some with unique multi-lobed nuclei, frequently arranged in a reticular pattern and supported by a myxoid stroma with focal laminations. Production of odontogenic hard tissues was also seen. Because of their unique microscopic features, both cases were investigated by next-generation sequencing and found to harbor the same STRN::ALK oncogene fusion. To our knowledge, these cases represent the first report of an odontogenic tumor with a STRN::ALK gene rearrangement. We propose the possibility that this neoplasm could be separate from other known odontogenic tumors. Both patients were treated with surgical resection and reconstruction. The prognosis of patients with this entity is currently uncertain but shall become more apparent over time as more cases are identified and followed. [ABSTRACT FROM AUTHOR]

Ameloblastoma is a rare tumor but represents the most common odontogenic neoplasm. It is localized in the jaws and, although it is a benign, slow-growing tumor, it has an aggressive local behavior and high recurrence rate. Therefore, alternative treatment options or complementary to surgery have been evaluated, with the most promising one among them being a targeted therapy with the v-Raf murine sarcoma viral oncogene homologue B (BRAF), as in ameloblastoma the activating mutation V600E in BRAF is common. Studies in other tumors have shown that the synchronous inhibition of BRAF and human murine double minute 2 homologue (MDM2 or HDM2) protein is more effective than BRAF monotherapy, particularly in the presence of wild type p53 (WTp53). To investigate the MDM2 protein expression and gene amplification in ameloblastoma, in association with BRAFV600E and p53 expression. Forty-four cases of ameloblastoma fixed in 10% buffered formalin and embedded in paraffin were examined for MDM2 overexpression and BRAFV600E and p53 expression by immunohistochemistry, and for MDM2 ploidy with fluorescence in situ hybridization. Sixteen of forty-four (36.36%) cases of ameloblastoma showed MDM2 overexpression. Seven of sixteen MDM2-positive ameloblastomas (43.75%) were BRAFV600E positive and fifteen of sixteen MDM2-positive ameloblastomas (93.75%) were p53 negative. All MDM2 overexpressing tumors did not show copy number alterations for MDM2. Overexpression of MDM2 in ameloblastomas is not associated with MDM2 amplification, but most probably with MAPK activation and WTp53 expression. Further verification of those findings could form the basis for the use of MDM2 expression as a marker of MAPK activation in ameloblastomas and the trial of dual BRAF/MDM2 inhibition in the management of MDM2-overexpressing/BRAFV600E-positive/WTp53 ameloblastomas. [ABSTRACT FROM AUTHOR]