Odontogenic cysts, odontogenic tumors, fibroosseous, and giant cell lesions of the jaws

Identification of Molecular Mechanisms of Ameloblastoma and Drug Repositioning by Integration of Bioinformatics Analysis and Molecular Docking Simulation

Background

Ameloblastoma (AM) is a benign tumor locally originated from odontogenic epithelium that is commonly found in the jaw. This tumor makes aggressive invasions and has a high recurrence rate. This study aimed to investigate the differentially expressed genes (DEGs), biological function alterations, disease targets, and existing drugs for AM using bioinformatics analysis.

Methods

The data set of AM was retrieved from the GEO database (GSE132474) and identified the DEGs using bioinformatics analysis. The biological alteration analysis was applied to Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways. Protein-protein interaction (PPI) network analysis and hub gene identification were screened through NetworkAnalyst. The transcription factor-protein network was constructed via OmicsNet. We also identified candidate compounds from L1000CDS2 database. The target of AM and candidate compounds were verified using docking simulation.

Results

Totally, 611 DEGs were identified. The biological function enrichment analysis revealed glycosaminoglycan and GABA (γ-aminobutyric acid) signaling were most significantly up-regulated and down-regulated in AM, respectively. Subsequently, hub genes and transcription factors were screened via the network and showed FOS protein was found in both networks. Furthermore, we evaluated FOS protein to be a therapeutic target in AMs. Candidate compounds were screened and verified using docking simulation. Tanespimycin showed the greatest affinity binding value to bind FOS protein.

Conclusions

This study presented the underlying molecular mechanisms of disease pathogenesis, biological alteration, and important pathways of AMs and provided a candidate compound, Tanespimycin, targeting FOS protein for the treatment of AMs.

Multiple odontogenic keratocysts in a patient with Lowe syndrome: a first case report and literature review

Lowe syndrome (LS) is a rare disease (1:500,000) with X-linked recessive inheritance involving the kidneys, eyes, and nervous system. A Mexican 25-year-old male patient presented for diagnosis of multiple radiolucent lesions observed on routine radiographic examination. General aspects revealed cognitive delay, eye alterations, and kidney involvement, which support the diagnosis of LS. Radiolucent well-delimited lesions were observed in both mandibular angle and symphysis. Under general anesthesia, incisional biopsy and decompression were performed. Histological aspects led to diagnosing odontogenic keratocyst (OKC) for all lesions. The lesions in the right and left mandibular angles were decompressed, and the symphyseal lesion was enucleated. A 2-month follow-up shows the bone healing process. There are few reports detailing oral findings in LS. Here, we reported the first case of multiple OKC in a patient with LS. In addition, we performed a literature review on odontogenic lesions in patients affected by LS.

Analysis of the 100 most cited articles on ameloblastoma

OBJECTIVES

An increasing number of articles are published each year. The aim of this is to provide a list of the 100 most cited articles on the subject of ameloblastoma.

METHODS

A bibliographic search was performed on Google Scholar (GS), Microsoft Academic (MA), and Dimensions for ameloblastoma. A ranking was created in order of citation density. Graphical representations of keywords and authorship were created with VOSviewer. Statistical analysis was performed and only results with a 95% confidence interval were considered significant.

RESULTS

A helpful list of top 100 articles was developed to help professionals in a variety of ways. Some curiosities are discussed about this scientometric analysis in ameloblastoma articles.

CONCLUSIONS

A useful list of the top 100 most cited articles on ameloblastoma has been provided. Bibliometric and altmetric analysis using Google Scholar, Microsoft Academic, and Dimensions is a free and excellent tool, not only as a citation manager but also as a study reference.

Spectrum of Oral and Maxillofacial Tissue Biopsies at the Foremost Tertiary Institution in The Gambia: A Retrospective Review

Introduction

Sub-Saharan Africa has a heavy burden of oral diseases and cancers. Also, there is a dearth of published records of oral pathology services in The Gambia. Therefore, this review aimed to determine the prevalence of biopsied oral and maxillofacial lesions in order to ascertain the uptake of oral histopathology services at the foremost tertiary institution in The Gambia.

Materials and Methods

This was a retrospective study performed at the Pathology Department of Edward Francis Small Teaching Hospital. Reports of all oral and maxillofacial biopsies submitted for the period 2012 to 2021 were reviewed and data were extracted. Descriptive analysis was done using SPSS software, version 26.

Results

Total number of biopsy reports was 158 representing 0.02% over the study period. The mean age of patients was 34.3 ± 19.7 years, the 3rd decade was the peak age of presentation and male-to-female ratio was 1:1.6. Majority (65/41.1%) of the cases were benign neoplastic lesions, and the mandible was the most (21/13.3%) common site of biopsy. Reactive lesions were the predominant (34/21.5%) group and squamous cell carcinoma had the highest (24/15.3%) number of lesions while odontogenic tumours constituted six cases only (3.8%).

Conclusion

The findings of this study showed low uptake of oral histopathology services while biopsied oral and maxillofacial lesions were prevalent in female patients in the third decade of life. Also, the mandible was the most affected site whereas benign neoplastic diagnoses were most common. However, this study recorded a higher proportion of malignancies than some previous studies.

Maxillary neoplasms in four dromedary camels

Four camels (Camelus dromedarius) presented to the Veterinary Teaching Hospital at King Faisal University with maxillary masses. On radiographs, the masses were multicystic and expanded the maxillary bone. The tumors were diagnosed by histopathologic examination as conventional ameloblastoma, two cases as intraosseous squamous cell carcinoma, and central odontogenic fibroma with ossification. To the authors' knowledge, this is the first report of ameloblastoma in a camel, the first detailed description of maxillary squamous cell carcinoma in camels, and the first report of central odontogenic fibroma in any animal species.

The Three-Dimensional Evaluation of Radicular Cyst by Cone-Beam Computed Tomography

A radicular cyst is the most typical odontogenic cyst affecting the human jaws. A radicular cyst is frequently asymptomatic and is discovered accidentally during a radiological procedure. Radicular cyst most commonly occurs during the third and fourth decades of life. The patient affected by a radicular cyst usually gives a history of trauma, and they may even not be aware of the occurrence of the traumatic episode. Such a case of a Radicular cyst that occurred in a 22-year-old-young female who did not follow up further for root canal treatment was radiographically evaluated in three-dimensional view with the help of cone-beam computed tomography.

Pharmacological management of cherubism: A systematic review

OBJECTIVE

The aim of this systematic review was to determine if there exists an efficacious drug treatment for cherubism, based on published studies.

METHODS

This systematic review included observational case studies reporting pharmacological management of cherubism. We developed specific search strategies for PubMed (including Medline), ScienceDirect, Web of Science. We evaluated the methodological quality of the included studies using criteria from the Joanna Briggs Institute's critical appraisal tools.

RESULTS

Among the 621 studies initially identified by our search script, 14 were selected for inclusion, of which five were classified as having a low risk of bias, four as having an unclear risk, and five a high risk. Overall, 18 cherubism patients were treated. The sample size in each case study ranged from one to three subjects. This review identified three types of drugs used for cherubism management: calcitonin, immunomodulators and anti-resorptive agents. However, the high heterogeneity in case reports and the lack of standardized outcomes precluded a definitive conclusion regarding the efficacy of any treatment for cherubism.

CONCLUSIONS

The present systematic review could not identify an effective treatment for cherubism due to the heterogeneity and limitations of the included studies. However, in response to these shortcomings, we devised a checklist of items that we recommend authors consider in order to standardize the reporting of cherubism cases and specifically when a treatment is given toward identification of an efficacious cherubism therapy.

SYSTEMATIC REVIEW REGISTRATION

https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42022351044, identifier CRD42022351044.

Radiomics in bone pathology of the jaws

OBJECTIVE

To define which are and how the radiomics features of jawbone pathologies are extracted for diagnosis, predicting prognosis and therapeutic response.

METHODS

A comprehensive literature search was conducted using eight databases and gray literature. Two independent observers rated these articles according to exclusion and inclusion criteria. 23 papers were included to assess the radiomics features related to jawbone pathologies. Included studies were evaluated by using JBI Critical Appraisal Checklist for Analytical Cross-Sectional Studies.

RESULTS

Agnostic features were mined from periapical, dental panoramic radiographs, cone beam CT, CT and MRI images of six different jawbone alterations. The most frequent features mined were texture-, shape- and intensity-based features. Only 13 studies described the machine learning step, and the best results were obtained with Support Vector Machine and random forest classifier. For osteoporosis diagnosis and classification, filtering, shape-based and Tamura texture features showed the best performance. For temporomandibular joint pathology, gray-level co-occurrence matrix (GLCM), gray level run length matrix (GLRLM), Gray Level Size Zone Matrix (GLSZM), first-order statistics analysis and shape-based analysis showed the best results. Considering odontogenic and non-odontogenic cysts and tumors, contourlet and SPHARM features, first-order statistical features, GLRLM, GLCM had better indexes. For odontogenic cysts and granulomas, first-order statistical analysis showed better classification results.

CONCLUSIONS

GLCM was the most frequent feature, followed by first-order statistics, and GLRLM features. No study reported predicting response, prognosis or therapeutic response, but instead diseases diagnosis or classification. Although the lack of standardization in the radiomics workflow of the included studies, texture analysis showed potential to contribute to radiologists' reports, decreasing the subjectivity and leading to personalized healthcare.

Endoscopic-assisted approaches for enucleation of invaded sinonasal region by benign odontogenic cysts: a case series study

Background

During surgical planning for the excision of odontogenic cysts and tumors, surgeons should consider choosing the appropriate endoscopic approach to reach all parts of the maxillary sinus and cyst walls during its enucleation. Using the endoscopic trans-nasal approaches results in less than one-third of the maxillary sinus being reached regardless of antrostomy or angled instruments used. Also, the expansion process and involvement of maxillary sinuses in odontogenic cysts and tumors are variable, adding more difficulties during excision. This study aimed to assess the expansion process of large benign odontogenic cysts and tumors involving nasoantral regions and adaptability to different endoscopic approaches for enucleation. Six patients were included in this case series study. Preoperative panoramic views plain film radiography, and computed tomography scans were obtained. Lesion characteristics, relation to teeth origin, the nose, and maxillary sinus wall displacement, location of lesions about typical vertical and horizontal nasomaxillary constructions, and associated inflammation of the paranasal sinuses were evaluated. Three surgical approaches were tailored, allowing viewing and endoscopic enucleation.

Results

Four periapical (radicular) cysts, one ameloblastoma, and one calcifying epithelial odontogenic tumor, ranging in size from 3 to 5 cm, were enucleated endoscopically in patients aged 15–40 years. Intra-sinus expansion of the cyst and lesion level above the nasal floor allowed endoscopic enucleation using wide middle meatal antrostomy in 1 (17%). Lesions localized to the anterior wall and the nasal process of the maxilla permitted endonasal minimal rhinotomy approach in 1 (17%). Central lesions, cyst extension below the level of the nasal floor, and lateral wall expansion with or without anterior maxillary wall scalloping had adequate exposure using a minimal sublabial approach in four patients (67%). Together with its role in complete enucleation, endoscopy allowed associated rhinosinusitis surgical treatment in five patients (83%).

Conclusion

Tailoring surgical approaches to the expansion process allowed endoscopic enucleation of large odontogenic cysts/tumors without wall remnants. The integrity of the Schneiderian membrane was preserved, protecting the critical surrounding structures.

Imaging Features of Craniofacial Giant Cell Granulomas: A Large Retrospective Analysis from a Tertiary Care Center

BACKGROUND AND PURPOSE

Craniofacial giant cell granulomas are rare lesions with varied appearances on imaging. We aimed to describe the imaging features of giant cell granulomas of the craniofacial bones.

MATERIALS AND METHODS

A retrospective analysis of the clinical features and imaging findings of 20 histopathology-proved cases of craniofacial giant cell granulomas, dating from 2006 to 2022, was performed.

RESULTS

Of the 20 cases, 10 each were seen in men and women. The epicenter of the lesions varied in location: in the maxilla in 8 patients, in the mandible in 5, in the temporal bone in 3, in the sphenoid/clivus in 3, and in the orbit in 1 patient. On the radiographs, the lesions appeared well-circumscribed, expansile, and lytic. On CT, the lesions were predominantly multiloculated, with thin septa, a soft-tissue component, and with expansion and remodeling of the underlying bone. On MR imaging, the solid component of the lesions was isointense on T1WI and hypointense on T2WI, with heterogeneous enhancement of the solid component and rim enhancement of the locules. Fluid-fluid levels were present in 3 patients.

CONCLUSIONS

Giant cell granulomas commonly present as locally aggressive, expansile, multiloculated lytic lesions, with solid as well as cystic areas. The solid component is typically hypointense on T2WI. Certain key imaging features of giant cell granulomas can aid the radiologist in narrowing the differential diagnosis.

Modified Carnoy's Compared to Carnoy's Solution Is Equally Effective in Preventing Recurrence of Odontogenic Keratocysts

PURPOSE

Carnoy's solution (CS), the gold standard for adjunctive chemical cautery in treatment of odontogenic keratocysts (OKCs), has been banned for 7 years, leading to substitution with the non-chloroform containing modified Carnoy's solution (MC) without data to support its effectiveness. We performed this study to compare the earlier data with CS to the more current outcomes with MC.

METHODS

A retrospective cohort study was conducted on patients diagnosed with OKC and treated by a single surgeon (GHB) with enucleation and curettage (EC), peripheral ostectomy, and application of CS or MC. The primary predictor variables were use of CS or MC. The primary outcome variables were recurrence (yes vs. no) and time to recurrence. Secondary variables included demographics, anatomic location, and whether teeth adjacent to the lesion were extracted. Statistical analyses included chi-squared test/Fisher's exact test, Wilcoxon rank sum test, and Kaplan-Meier curves.

RESULTS

77 patients, 36 patients in the CS group and 41 in the MC group, met inclusion criteria, including at least 1 year of follow-up time. Characteristics of the groups were similar: median age 41.5 and 46, 61% and 71% male gender, 81% and 90% posterior, and 64% and 50% mandibular lesions, respectively. Overall recurrence was similar, 14.29%, with 5 (13.9%) recurrences in the CS group and 6 (14.6%) in the MC group (P = 0.92). Median time to recurrence was 24 months for both groups. Preserving adjacent teeth was associated with a significant increase in recurrence (P = 0.0036).

CONCLUSION

Based on this comparison of retrospective outcome data, we found no significant difference in recurrence rate or distribution of time to recurrence between OKCs treated with CS or MC. Aggressiveness of surgical technique is likely a predictive factor in recurrence rate. Future studies should focus on prospective studies and continuing follow-up of the MC group.

Cutaneous Keratocyst With D2-40 Immunoreactivity in Basal Cell Nevus Syndrome

ABSTRACT

Although not a diagnostic criterion for basal cell nevus syndrome (BCNS, OMIM#109400), cutaneous cysts, particularly epidermoid cysts, are common in this condition. Cutaneous keratocysts, on the other hand, are extremely rare in general and have been identified in only 5 patients with BCNS. Here, we describe a BCNS patient with a cutaneous keratocyst that demonstrated D2-40 (podoplanin) immunoreactivity, which has been detected in odontogenic keratocysts but not cutaneous keratocysts. This finding suggests that cutaneous keratocysts may be developmentally homologous to odontogenic keratocysts and may behave similarly in terms of invasion and growth pattern.

Multiple versus solitary giant cell lesions of the jaw: Similar or distinct entities?

The majority of giant cell lesions of the jaw present as a solitary focus of disease in bones of the maxillofacial skeleton. Less frequently they occur as multifocal lesions. This raises the clinical dilemma if these should be considered distinct entities and therefore each need a specific therapeutic approach. Solitary giant cell lesions of the jaw present with a great diversity of symptoms. Recent molecular analysis revealed that these are associated with somatic gain-of-function mutations in KRAS, FGFR1 or TRPV4 in a large component of the mononuclear stromal cells which all act on the RAS/MAPK pathway. For multifocal lesions, a small group of neoplastic multifocal giant cell lesions of the jaw remain after ruling out hyperparathyroidism. Strikingly, most of these patients are diagnosed with jaw lesions before the age of 20 years, thus before the completion of dental and jaw development. These multifocal lesions are often accompanied by a diagnosis or strong clinical suspicion of a syndrome. Many of the frequently reported syndromes belong to the so-called RASopathies, with germline or mosaic mutations leading to downstream upregulation of the RAS/MAPK pathway. The other frequently reported syndrome is cherubism, with gain-of-function mutations in the SH3BP2 gene leading through assumed and unknown signaling to an autoinflammatory bone disorder with hyperactive osteoclasts and defective osteoblastogenesis. Based on this extensive literature review, a RAS/MAPK pathway activation is hypothesized in all giant cell lesions of the jaw. The different interaction between and contribution of deregulated signaling in individual cell lineages and crosstalk with other pathways among the different germline- and non-germline-based alterations causing giant cell lesions of the jaw can be explanatory for the characteristic clinical features. As such, this might also aid in the understanding of the age-dependent symptomatology of syndrome associated giant cell lesions of the jaw; hopefully guiding ideal timing when installing treatment strategies in the future.

Ghost cell odontogenic carcinoma of the left maxilla

We report the case of a 25-year-old man with a maxillary ghost cell odontogenic carcinoma (GCOC). The patient presented to the maxillofacial and head and neck surgery clinic with a growing lump in the left maxilla. Initial workup with CT revealed a cystic lesion in the left upper jaw with associated bone erosion and an enhancing soft-tissue component. Enucleation showed a GCOC associated with a calcifying odontogenic cyst. After the diagnosis was obtained, the patient underwent widening of the first surgical resection. GCOCs are rare odontogenic neoplasms with unspecific clinical and imaging presentation, whose definitive characterisation is based on pathology. Current treatment approaches mainly involve surgical excision, but the prognosis is highly unpredictable due to intertumoral heterogeneity. As tumour recurrences occur in 73% of cases, radical surgery with negative margins is highly recommended. Therefore, it is essential to recognise this entity to offer patients adequate management.

Dentinogenic Ghost Cell Tumor in a Sumatran Rhinoceros

Simple Summary

A dentinogenic ghost cell tumor is an odontogenic ghost cell lesion of the maxilla and mandible. It is a rare tumor that has been described in humans. This work describes the clinical and pathological findings of an advanced stage of a dentinogenic ghost cell tumor, a type that has not previously been described in veterinary medicine. The advanced stage of this tumor led to the observation of aberrant keratinization, characterized by ghost cells and numerous islands of dentinoid formation. Diagnosis was made with the aid of routine histology, special histochemistry, immunohistochemistry, and classification and features from human oncology as a reference.

Abstract

An adult female Sumatran rhinoceros was observed with a swelling in the left infraorbital region in March 2017. The swelling rapidly grew into a mass. A radiograph revealed a cystic radiolucent area in the left maxilla. In June 2017, the rhinoceros was euthanized. At necropsy, the infraorbital mass measured 21 cm × 30 cm. Samples of the infraorbital mass, left parotid gland, and left masseter muscle were collected for histopathology (Hematoxylin & Eosin, Von Kossa, Masson’s trichrome, cytokeratin AE1/AE3, EMA, p53, and S-100). Numerous neoplastic epithelial cells showing pleomorphism and infiltration were observed. Islands of dentinoid material containing ghost cells and keratin pearls were observed with the aid of the two special histochemistry stains. Mitotic figures were rarely observed. All the neoplastic odontogenic cells and keratin pearls showed an intense positive stain for cytokeratin AE1/AE3, while some keratin pearls showed mild positive stains for S-100. All samples were negative for p53 and S-100 immunodetection. The mass was diagnosed as a dentinogenic ghost cell tumor.

Differential diagnosis of ameloblastoma and odontogenic keratocyst by machine learning of panoramic radiographs

Purpose

The differentiation of the ameloblastoma and odontogenic keratocyst directly affects the formulation of surgical plans, while the results of differential diagnosis by imaging alone are not satisfactory. This paper aimed to propose an algorithm based on convolutional neural networks (CNN) structure to significantly improve the classification accuracy of these two tumors.

Methods

A total of 420 digital panoramic radiographs provided by 401 patients were acquired from the Shanghai Ninth People’s Hospital. Each of them was cropped to a patch as a region of interest by radiologists. Furthermore, inverse logarithm transformation and histogram equalization were employed to increase the contrast of the region of interest (ROI). To alleviate overfitting, random rotation and flip transform as data augmentation algorithms were adopted to the training dataset. We provided a CNN structure based on a transfer learning algorithm, which consists of two branches in parallel. The output of the network is a two-dimensional vector representing the predicted scores of ameloblastoma and odontogenic keratocyst, respectively.

Results

The proposed network achieved an accuracy of 90.36% (AUC = 0.946), while sensitivity and specificity were 92.88% and 87.80%, respectively. Two other networks named VGG-19 and ResNet-50 and a network trained from scratch were also used in the experiment, which achieved accuracy of 80.72%, 78.31%, and 69.88%, respectively.

Conclusions

We proposed an algorithm that significantly improves the differential diagnosis accuracy of ameloblastoma and odontogenic keratocyst and has the utility to provide a reliable recommendation to the oral maxillofacial specialists before surgery.

Comparison of calretinin expression in dentigerous cysts and ameloblastoma: An immunohistochemical study

Background:

Calretinin is a calcium-binding protein of 29-kilodalton (kDa), which is widely expressed in normal human tissues and tumorigenic tissues. Its expression in the odontogenic epithelium during odontogenesis and in neoplastic odontogenic tissues has been demonstrated. Unicystic ameloblastoma poses a diagnostic challenge, as its histologic presentation can be sometimes mistaken for cystic odontogenic lesions. In the present study, an attempt is made to overcome the confusion encountered in the diagnosis of dentigerous cyst and unicystic ameloblastoma, using the expression of calretinin in both lesions and to compare this expression with conventional ameloblastoma to accurately diagnose and differentiate these lesions.

Materials and Methods:

A total of eighty cases, in which twenty cases each of ameloblastoma, unicystic ameloblastoma, dentigerous cyst, and odontogenic keratocyst (OKC) were included in the study. Slides were made from the archival blocks of each case and were stained immunohistochemically with calretinin.

Results:

Correlation between calretinin staining and histopathological diagnosis was done, and it was found that all twenty cases of ameloblastoma showed positivity for calretinin, whereas 17 of twenty cases of unicystic ameloblastoma showed positivity for calretinin staining. All the cases of OKC and dentigerous cyst were negative for calretinin.

Conclusion:

Calretinin may serve as an important diagnostic adjunct in the differential diagnosis of ameloblastoma and cystic odontogenic lesions.

SATB2 is not a reliable diagnostic marker for distinguishing between oral osteosarcoma and fibro-osseous lesions of the jaws

OBJECTIVE

Special AT-rich binding protein 2 (SATB2) is an immunohistochemical marker for osteoblast differentiation. Our aim was to investigate SATB2 expression in oral osteosarcoma and other bone-producing oral tumors/reactive lesions to evaluate its usefulness as a diagnostic marker.

STUDY DESIGN

A total of 74 intraosseous and soft tissue bone-producing surgical samples and 10 samples of reactive bone tissue were stained with SATB2, including osteosarcoma/chondrosarcoma (n = 16), fibro-osseous lesions (n = 42), central giant cell granuloma (n = 6), osteoblastoma (n = 1), and gingival lesions (n = 9). Nuclear labeling of the stromal spindle cells and intensity of staining was scored and analyzed.

RESULTS

The intraosseous (n = 65/65) and soft tissue samples (n = 9/9) diffusely expressed SATB2. The strongest expression was observed in juvenile aggressive ossifying fibroma (n = 2/2). Weak SATB2 expression was observed in the stromal spindle cells adjacent to reactive bone tissue (periosteal bone reaction).

CONCLUSIONS

Our results indicate that SATB2 is not a reliable diagnostic marker for oral osteosarcoma but has practical use in detecting cells with osteoblast differentiation in histologic samples with scant bone production or in differentiating between a periosteal bone reaction and neoplastic bone induced by the tumor mesenchymal cells. Targeting SATB2 as an alternative therapy in oral osteosarcoma, fibro-osseous lesions, and central giant cell granuloma should be further investigated.

Odontogenic myxoma: ambiguous pathology of anterior maxilla

Swellings in the anterior maxilla are uncommon and if present can be deemed as paradoxical conundrums presenting diagnostic and therapeutic dilemmas. Odontogenic myxoma is a rare, locally aggressive lesion that is primarily seen affecting the mandibular posterior region in association with an impacted tooth. It is found to be associated with odontogenesis. Treatment is usually surgical, with extent varying from curettage to resection. This report describes a rare case of odontogenic myxoma of the anterior maxilla in a 14-year-old boy, with an emphasis on its epidemiology, clinical presentation, histopathology, diagnosis and treatment planning.

Multiple radiolucencies in the mandible: A diagnostic dilemma

Diagnosis and treatment planning of maxillofacial pathologies is an art. It requires careful evaluation and correlation of clinical presentation and radiologic investigations. When the pathology concerned is an intraosseous lesion, the radiographic findings assume a significantly more important role. While carrying out the radiographic assessment, we rely on typical findings regarding the number, location, and appearance of radiolucent areas which point towards certain types of pathologies. Whenever these findings are atypical or at variance with the clinical presentation, it creates a diagnostic dilemma for the clinician. We report a case of a 34-year-old man who presented with a simple clinical history but multiple radiolucencies on the radiograph.

Central Odontogenic Fibroma with Giant Cell Granuloma-Like Lesion: A Report of an Additional Case and Review of Literature

Central odontogenic fibroma is a rare benign odontogenic tumor that relies on clinical-radiographic-histological correlation to reach its diagnosis, especially its rare variants. Of these rare types is the coexistence of giant cell granuloma-like lesion, with the characteristic odontogenic epithelial rests. The presented case is a 33 years old female complaining of asymptomatic mandibular bony swelling. Radiographically, the lesion is unilocular radiolucent, without root resorption. Histological examination revealed the presence of multinucleated giant cells within the diagnosed central odontogenic fibroma. Immunohistochemical staining highlighted the presence of both components.

Cell-block as ancillary tool for the diagnosis of cystic and cyst-like jaw lesions

BACKGROUND

The cell-block technique is a cytological diagnostic method that decreases cellular dispersion; however, its usefulness regarding intraosseous lesions is underexplored. Therefore, this study aimed to assess the diagnostic usefulness of cell-block for cystic and cyst-like jaw lesions.

METHODS

Individuals with cystic or cyst-like jaw lesions who underwent aspiration biopsy were considered eligible. Aspiration of luminal content was prepared and processed by the cell-block technique. Cytological evaluations were blindly performed by two trained PhD students (in a single evaluation) and one oral and maxillofacial pathologist (OMP). Cohen's kappa statistic was used to measure inter-rater agreement.

RESULTS

The sample was composed of 52 lesions, represented by 25 radicular cysts (RC), 17 odontogenic keratocysts (OKC), 5 idiopathic bone cavities (IBC), and 5 unicystic ameloblastomas (UA). The kappa coefficient of cell-block compared to histopathological diagnosis was 0.390 (95% confidence interval [95%CI], 0.195-0.585) for PhD students and 0.612 (95%CI, 0.433-0.791) for the OMP. The highest concordance rates between cell-block and histopathological diagnosis were observed for RC (PhD = 76.0%; OMP = 80.0%) and OKC (PhD = 58.8%; OMP = 76.5%). Conflicting results were found regarding IBC (PhD = 40.0%; OMP = 80.0%) and UA, that presented the overall lowest concordance rates (PhD = 20.0%; OMP = 40.0%).

CONCLUSION

The cell-block technique presented a high diagnostic usefulness for detecting RC and OKC and, if associated with clinical and radiographic characteristics, might be sufficient for final diagnosis of these diseases. Regarding IBC and UA, an analysis with a higher number of cases is recommended to determine the true usefulness of the cell-block as ancillary tool for the diagnosis of these lesions.

Management of an extensive odontogenic keratocyst: A rare case report with 10-year follow-up

INTRODUCTION

The odontogenic keratocyst (OKC), previously known as keratocystic odontogenic tumor has been the most disputable pathologies of the maxillofacial region. Patients with OKC are often asymptomatic but may present with pain, swelling, or discharge. Despite the aggressive nature, previous literature as early as 1970s reported the fact that parakeratinized OKC can be treated by means of marsupialization alone.

PATIENTS CONCERNS

The patient had reported with a complaint of pain and swelling in relation with a tooth in mandibular right quadrant.

DIAGNOSIS

This case report discusses features of a rare, extensive, panmandibular OKC that is only second of its kind mentioned in the literature.

INTERVENTION

As a usual treatment protocol, marsupialization was attempted first. Immunohistochemical analysis revealed reduced expression of Ki-67 and B cell lymphoma 2 (bcl-2) markers after marsupialization from 2 separate sites. However, due to incomplete resolution in the lower right anterior region, an aggressive approach was taken by curetting it out surgically along with associated teeth and cortical plate followed by application of Carnoy's solution.

OUTCOME

Postsurgery uneventful healing of the lesion was noted on regular follow-up visits with complete resolution at 40 months. The case has been followed for 10 years with no sign of relapse and reoccurrence.

CONCLUSIONS

Based on the expression of markers it can thus be concluded that Ki-67 and bcl-2 are site specific and bear strong relationship with the recurrence of OKCs.

Loss of the PTCH1 tumor suppressor defines a new subset of plexiform fibromyxoma

BACKGROUND

Plexiform fibromyxoma (PF) is a rare gastric tumor often confused with gastrointestinal stromal tumor. These so-called "benign" tumors often present with upper GI bleeding and gastric outlet obstruction. It was recently demonstrated that approximately one-third of PF have activation of the GLI1 oncogene, a transcription factor in the hedgehog (Hh) pathway, via a MALAT1-GLI1 fusion protein or GLI1 up-regulation. Despite this discovery, the biology of most PFs remains unknown.

METHODS

Next generation sequencing (NGS) was performed on formalin-fixed paraffin-embedded (FFPE) samples of PF specimens collected from three institutions (UCSD, NCI and OHSU). Fresh frozen tissue from one tumor was utilized for in vitro assays, including quantitative RT-PCR and cell viability assays following drug treatment.

RESULTS

Eight patients with PF were identified and 5 patients' tumors were analyzed by NGS. An index case had a mono-allelic PTCH1 deletion of exons 15-24 and a second case, identified in a validation cohort, also had a PTCH1 gene loss associated with a suspected long-range chromosome 9 deletion. Building on the role of Hh signaling in PF, PTCH1, a tumor suppressor protein, functions upstream of GLI1. Loss of PTCH1 induces GLI1 activation and downstream gene transcription. Utilizing fresh tissue from the index PF case, RT-qPCR analysis demonstrated expression of Hh pathway components, SMO and GLI1, as well as GLI1 transcriptional targets, CCND1 and HHIP. In turn, short-term in vitro treatment with a Hh pathway inhibitor, sonidegib, resulted in dose-dependent cell killing.

CONCLUSIONS

For the first time, we report a novel association between PTCH1 inactivation and the development of plexiform fibromyxoma. Hh pathway inhibition with SMO antagonists may represent a target to study for treating a subset of plexiform fibromyxomas.

Glandular Odontogenic Cyst in Dentigerous Relationship: An Uncommon Case Report

Glandular odontogenic cyst (GOC) is an uncommon cyst of the jaw. Less than 200 cases are reported in the literature, and only 22 cases are associated with an unerupted tooth (dentigerous relationship). Although it is an asymptomatic lesion, it can be destructive and has high recurrence rates. The diagnosis can be especially challenging due to the lack of distinct diagnostic clinic-radiological criteria and nonspecific microscopic features, mimicking benign and malignant lesions. Conservative surgical treatment has been the choice for most surgeons, but marginal or partial jaw resection has been reported. This report describes a rare case of GOC in a dentigerous relationship, which was treated with enucleation and peripheral osteotomy.

Expression of p63 in tooth germ, dentigerous cyst and ameloblastoma

Context:

To assess the role of p63, a p53 homolog, in the cytodifferentiation (odontogenesis) and oncogenesis of odontogenic epithelium.

Aim:

The present study aimed to compare the expression pattern of p63 in the epithelium of tooth germ, dentigerous cyst (DC) and ameloblastoma (AB).

Materials and Methods:

Tissue specimens of thirty tooth germs, thirty ABs and thirty DCs were examined by immunohistochemistry for the expression of p63. Results: p63 labeling index (LI) was observed in descending order in epithelial cells of ABs, tooth germs and DCs. p63 LI was statistically nonsignificant among all the three groups. ABs revealed the highest p63 expression, but, surprisingly, tooth germs showed higher expression than DCs.

Conclusion:

p63 plays a role in the cytodifferentiation and proliferation of odontogenic epithelial cells irrespective of the tissue (normal developing or lesional tissue). This implies that p63 cannot be used as a diagnostic marker. However, our results indicate p63 overexpression as a mark of increased proliferation. Thus, it can be stipulated that p63 can be used as a prognostic marker in odontogenic lesions with more aggressive and invasive phenotype. Our results also suggest the differential function of p63 in both developing and lesional odontogenic tissues, which, however, depends on p63 isoform predominantly being expressed. Therefore, identification of p63-predominant isoform in a particular lesion is more important than the presence or absence of p63. Consequently, we suggest the performance of polymerase chain reaction analysis along with immunohistochemical evaluation in further studies.

An Analysis of Clinical and Histopathologic Features of Fibrous Dysplasia of the Jaws: A Series of 40 Cases and Review of Literature

Fibrous dysplasia (FD) is a rare condition commonly involving the jaws. While FD has a typical clinical and histological presentation, considerable variation exists. Moreover, overlap of features with other disorders is possible. This study serves to characterize the features of a large case series of FD of the jaws. With IRB approval, the University of Florida Oral Pathology Biopsy Service archive was retrospectively searched from 1994 to 2015 for cases of FD. Epidemiological data, location, duration, clinical and radiographic appearance, clinical impression and exact microscopic diagnosis were recorded. The average age was 37.3 years (range 7-87 years) with majority of cases in females (67.5%). The most common ethnicity was Caucasian. Maxillary location was predominant (59%), followed by mandible (38%) and multiple locations (3%). Expansion was reported in 78% of cases. Radiographically, most cases exhibited ground glass opacity, however some presented with a mottled or mixed radiopaque/radiolucent appearance. Histologically, a wide variation in terms of stromal cellularity, presence of osteoblastic rimming, and presence of calcified material mimicking cemento-osseous dysplasia was observed. Clinicians and pathologists should be cognizant of the significant variability in clinical, histopathologic, and radiographic presentation of FD, which may pose a diagnostic challenge.

Investigation of Postoperative Complications of Intrabony Cystic Lesions in the Oral and Maxillofacial Region

PURPOSE

The purpose of this study was to identify factors that can complicate the surgical removal of intrabony cysts and any relevant correlations between them.

PATIENTS AND METHODS

The medical records of 249 patients who underwent surgical removal of intrabony cysts were retrospectively reviewed. Outcome variables were postoperative complications, infection, and recurrence. Predictor variables were patient age, gender, comorbidities, anatomic location, pathologic diagnosis, preoperative infection, previous marsupialization, and bone graft methods. Logistic regression analysis was performed to identify risk factors of postoperative infection and recurrence.

RESULTS

The cystic lesion was smallest in patients who did not receive a bone graft and increased steadily in those who received a xenogeneic bone graft and an autogenous bone graft, in that order. Paresthesia occurred after enucleation of the cystic lesion in 38 cases. Pathologic fractures were observed in 4 cases. There were 59 postoperative infections. The postoperative infection rate was as high as 63.6% in patients who underwent autogenous bone grafting. In contrast, infection rates were as low as 26.8 and 19.5% in those who underwent xenogeneic bone grafting and no bone grafting, respectively. Location of the cystic lesion in the maxilla or mandible affected the infection rate. When cysts were located in the anterior mandible, no postoperative infection occurred. In contrast, the infection rate was highest for cysts in the mandibular ramus, followed by those in the posterior mandible. Cystic lesion recurrence was observed in 7 cases: 5 cases of odontogenic keratocysts, 1 case of periapical cyst, and 1 case of dentigerous cyst. These findings suggest that cyst pathologic identity affects the recurrence rate. Cyst size was meaningfully correlated with recurrence rate.

CONCLUSIONS

These results suggest that autogenous bone grafts increase the risk of postoperative infection compared with absence of a bone graft.

Multidisciplinary oral rehabilitation of an adolescent suffering from juvenile Gorlin-Goltz syndrome - a case report

Background

The Gorlin-Goltz syndrome is an autosomal dominant disorder characterized by keratocystic odontogenic tumors in the jaws, multiple basal cell carcinomas and skeletal abnormities. Frequently, the manifestation of the syndrome occurs in the adolescent years.

Case presentation

An 11-year-old boy was referred to our clinic due to the persistence of the lower deciduous molars. The further diagnosis revealed bilateral keratocystic odontogenic tumors in the region of teeth 33 and 45 representing a symptom of a Gorlin-Goltz syndrome. This case of the oral rehabilitation of an adolescent with bilateral keratocystic odontogenic tumors shows the approach of a multidisciplinary treatment concept including the following elements: Enucleation and bone defect augmentation using a prefabricated bone graft; distraction osteogenesis to extend the graft-block vertically after cessation of growth; accompanying orthodontic treatment, guided implant placement and prosthetic rehabilitation. Six months after implant insertion, a new keratocystic odontogenic tumor in the basal part of the left sinus maxillaris had to be removed combined with the closure of the oroantral fistula. During the follow-up period of 18 months in semi-annual intervals, the patient showed no sign of pathology.

Conclusion

In the presented case could be shown that distraction osteogenesis of prefabricated bone blocks is possible. With a multidisciplinary approach in a long-term treatment a sufficient oral rehabilitation of the patient suffering from extended keratocystic odontogenic tumors was possible.

Multiple, Multiloculated, and Recurrent Keratocysts of the Mandible and Maxilla in Association with Gorlin-Goltz (Nevoid Basal-Cell Carcinoma) Syndrome: A Pediatric Case Report and Follow-up over 5 Years

Background

We report a case of multiple keratocysts first diagnosed in an 8-year-old boy.

Case report

The incidental radiographic finding of a cystic lesion in an 8-year-old boy led to the surgical enucleation and further diagnosis of a keratocyst associated with a tooth crown. In the course of dental maturation from deciduous to permanent teeth, the boy presented new lesions, always associated with the crowns of teeth. Gorlin-Goltz (nevoid basal-cell carcinoma) syndrome was suspected, and the genetic analysis detected a previously undescribed germline variant in the PTCH1 gene.

Treatment

This included a surgical removal of the cystic lesions, as well as the affected teeth.

Follow-up

Due to the high recurrence rate of the keratocysts, frequent radiological checks were performed over a 5-year period.

Molecular and cellular characterizations of human cherubism: disease aggressiveness depends on osteoclast differentiation

Background

Cherubism is a rare autosomal dominant disorder of the jaws caused by mutation of the SH3BP2 gene. The bone is replaced by a fibrous granuloma containing multinucleated giant cells. Cells of the cherubism granuloma have never been systematically analyzed. Hence, the aim of this study was to characterize the cells in human cherubism granulomas, to determine the osteoclastic characteristics of the multinucleated giant cells and to investigate the potential role of TNF-α in human cherubism.

Results

Seven granulomas were analyzed in pathology, molecular biology and immunohistochemistry. Granulomas were composed mainly of macrophages or osteoclasts within a fibroblastic tissue, with few lymphoid cells. Myeloid differentiation and nuclear NFATc1 localization were both associated with disease aggressiveness. OPG and RANKL immunohistochemical expression was unexpected in our specimens. Five granuloma cells were cultured in standard and osteoclastogenic media. In culture, cherubism cells were able to differentiate into active osteoclasts, in both osteoclastogenic and standard media. IL-6 was the major cytokine present in the culture supernatants.

Conclusion

Multinucleated giant cells from cherubism granulomas are CD68 positive cells, which differentiate into macrophages in non-aggressive cherubism and into osteoclasts in aggressive cherubism, stimulated by the NFATc1 pathway. This latter differentiation appears to involve a disturbed RANK-L/RANK/OPG pathway and be less TNF-α dependent than the cherubism mouse model.

Electronic supplementary material

The online version of this article (10.1186/s13023-018-0907-2) contains supplementary material, which is available to authorized users.

Diagnostic challenges of an unusually large schwannoma of the mandible: Report of a case

Schwannomas are slow-growing, benign neoplasms arising from the Schwann cells and are commonly reported as peripheral tumors in the head and neck region. Central intramandibular schwannomas are extremely rare lesions. We report a case of intramandibular schwannoma in a 70 year old male patient. Panoramic radiography revealed a large, multilocular radiolucent lesion with distinct borders involving the right mandibular body and ramus. A complete excision was achieved by removing the tumor followed by reconstruction of the mandible. The clinical, radiological, and histopathological features are discussed within the context of this case.

Bilateral Central Giant Cell Granuloma of the mandibular angle in three females from the same family

In literature there are few reports about multiple CGCG. But this is the first report of bilateral CGCG of the mandibular angles in three females from the same family.This report describes three cases of females from the same family - a mother and two young daughters - with bilateral CGCG in their jaw angles. All the lesions were surgically removed and the histopathologic diagnosis was always identical: giant cell central granulomas, with patterns that were absolutely superimposable between them and with that of the mother.The hypothesis is that this presentation of CGCG may be defined as hereditary bilateral CGCG of the mandibular angles (or also, cherubism-like lesions).

Third molar in the orbital floor: A precarious presentation of odontogenic keratocyst-A case report and review of literature

The case illuminates the likelihood of a dental pathology presenting with discrete signs and symptoms and the importance of the differential diagnosis of some incongruent clinical entities. The purpose of this article was to present a case report of odontogenic keratocyst (OKC) arising in the orbital floor, finding the common thread in rare pathology, and highlighting the aberration in our treatment plan by collating all the wealth of information published in the literature.

Is it a cystic or a cyst-like condition? Discussing the etiology of an unusual large mandibular lesion in a Roman skeleton from Quinta da Torrinha/Quinta de Santo António (Almada, Portugal)

Cystic and cyst-like lesions of the jaw are a recurrent finding in routine dental radiography but not in paleopathology. This paper describes a large oval osteolytic cavity (23 × 14 mm) observed in the mandible of a middle-aged female unearthed from the Roman necropolis of Quinta da Torrinha/Quinta de Santo António (Almada, Portugal, 3rd-5th centuries AD). The lesion was located in the body of the mandible, inferior to the alveolus of the first left molar. The associated tooth exhibited a carious lesion that destroyed the tooth crown and exposed the pulp cavity. The osteolytic lesion presented inner smooth walls and sharped regular contours, surrounded by slight microporosity. Radiography revealed an unilocular lesion with well-defined contours and a thin opaque rim. The differential diagnosis considered several odontogenic and non-odontogenic conditions of the jaw. The size and shape of the cavity, the nature of its walls and contours, and the presence of a source of infection in the pulp is consistent with an odontogenic condition of inflammatory origin, probably a radicular cyst.

Audit of Oral Histopathology Service at a Nigerian Tertiary Institution over a 24-Year Period

Background

Biopsies are often essential for definitive diagnosis of oro-facial lesions and are a part of oral diagnostic procedures carried out in histopathology laboratories. At present, there is paucity of literature on the audit of oral histopathology services in Nigeria. The objectives of this study were to determine the prevalence of biopsied oral lesions in a Nigerian tertiary institution. Also to profile the usage of oral pathology service and to identify challenges that may be present in an oral histodiagnostic service.

Methods

This was a retrospective study performed at the Oral Pathology Department of the University of Ibadan/ University College Hospital, Ibadan, Nigeria. Reports of all biopsies submitted at the Oral Pathology laboratory, for the period 1990-2014, were reviewed and data extracted. Descriptive analysis was done using SPSS software, version 20.

Results

The total number of reports was 1,998; invalid reports constituting 220(11%) were subsequently excluded leaving 1,778(89%) valid reports. The mean age of patients was 36.70±19.79, while the peak age of presentation was in the 3^rd decade. Male to female ratio was 1:1.1, and the mandible was the most common site of lesions 619(34.8%). These services were mainly utilized by oral surgeons (83.9%) and ameloblastoma (11.5%) was the most frequently diagnosed lesion. CD45 (16.7%) was the most frequently requested immuno-diagnostic test.

Conclusion

Biopsied oral lesions were more prevalent in females, while oral and maxillofacial surgeons utilized these services the most. Inadequate biopsy specimens or unrepresentative specimens and deficient documentation were challenges identified in this study.

Calcifying Odontogenic Cyst Associated With Dentigerous Cyst in a 15-Year-Old Girl

Calcifying odontogenic cyst (COC) is a rare odontogenic cyst with ameloblastic epithelial lining containing clusters of ghost cells. COCs have been described in association with several odontogenic tumors, more commonly odontomas and rarely with dentigerous cyst (DC). In this article, we describe a case of COC associated with DC in a 15-year-old girl, who presented with a swelling on the right middle third of the face, producing facial asymmetry. Panoramic radiography showed a well-circumscribed, corticated, and unilocular radiolucency at the level of the right maxillary sinus, involving 2 unerupted premolars. The lesion was enucleated and histologically revealed a COC associated with DC, which presented mucous metaplasia. Immunohistochemical reactions were performed to better illustrate this rare synchronous occurrence of COC and DC, showing positivity for CK5, CK14, CK19, and p63 in both lesions. CK18 was negative in COC, and Bcl-2 was negative in DC. Periodic acid Schiff highlighted the mucous cells in the DC lining.

Evaluation of mandibular odontogenic keratocyst and ameloblastoma by panoramic radiograph and computed tomography

OBJECTIVES:

The purpose of this study was to describe and compare the main imagenological features of mandibular ameloblastomas and odontogenic keratocyst (OKC) using panoramic radiograph (PR) and CT.

METHODS:

The sample consisted of nine cases of ameloblastomas and nine cases of OKC. PR and CT images were analyzed according to shape, internal structure, borders, associated unerupted tooth, root resorption, expansion and perforation of cortical bones.

RESULTS:

PR evaluation allowed the identification of the lesion's location, presence of sclerosis in the periphery, presence of associated non-erupted tooth and expansion of the mandible's lower border cortical bone. CT was more accurate than PR in the assessment of the lesion shape, presence of inner bone septa, root resorption, buccolingual expansion and rupture of cortical bone. Most cases of ameloblastoma and OKC presented buccolingual expansion and erosion of cortical bone. Only ameloblastomas showed tooth root resorption.

CONCLUSIONS:

Although PR is very helpful and widely used, CT provides more precise information on buccolingual expansion, calcification, bone septa, perforation of cortical bones and tooth resorption, features that are frequently underdescribed in the literature, particularly in OKC.

Giant dentinogenic ghost cell tumor: A case report

Dentinogenic ghost cell tumor (DGCT), a rare, benign odontogenic tumor with aggressive behavior, causes bone destruction and cortical expansion. We report here a case of DGCT in a 38-year-old male, presenting with enormous extraoral protrusion, which radiographically was predominantly radiolucent with radiopaque areas. Microscopically, it was observed to be a solid ameloblastomatous proliferation with pseudoglandular structures associated with clusters of ghost cells. Abundant dentinoid material adjacent to the epithelial sheets containing entrapped epithelial tumor cells was also evident. Immunohistochemistry revealed positivity for pan-cytokeratin (CK), CK-14, CK-7, and CK-19; CD138; and β-catenin. The Ki-67 proliferative index was very low (<1%). The clinical, histopathologic, and immunohistochemical features led to the diagnosis of DGCT. The patient underwent partial mandibulectomy, and no recurrences have occurred. To our knowledge, this is the largest DGCT described in the English language literature.

Immunohistochemical study of alpha-smooth muscle actin in odontogenic cysts and tumors

Context:

Myofibroblasts (MFs) are fibroblasts with smooth muscle-like features characterized by the presence of a contractile apparatus. Alpha-smooth muscle actin (α-SMA) is the actin isoform that predominates within vascular smooth muscle cells and plays an important role in fibrogenesis. MFs are metabolically and morphologically distinctive fibroblasts expressing α-SMA, and their activation plays a key role in development of the fibrotic response.

Aims and Objectives:

The aim of this study is to demonstrate the frequency, distribution and expression of α-SMA-positive MFs in odontogenic keratocyst (OKC), dentigerous cyst (DC) and ameloblastoma and correlate it to their aggressive biological behavior.

Settings and Design:

A retrospective study of 45 diagnosed cases, which includes 15 cases of OKC, 15 cases of DC and 15 cases of ameloblastoma, was undertaken to demonstrate expression of α-SMA retrieved from archives of our department.

Materials and Methods:

α-SMA mouse anti-human antibody and horseradish peroxidase detection system were used in this study.

Statistical Analysis:

Descriptive statistical analysis and ANOVA test were used for statistical analysis.

Results:

The difference in mean α-SMA count was found to be statistically significant between ameloblastoma and DC group (P < 0.001) as well as OKC and DC group (P < 0.001). No significant difference is observed between ameloblastoma and OKC group (P > 0.05). Results showed that mean number of stromal MFs in OKC and ameloblastoma were significantly higher than DC.

Conclusion:

The present study has shown that the mean number of MFs was higher in OKC and ameloblastoma, while the mean number of MFs in DC was quite low and significantly different from that of ameloblastoma and OKC.

Hybrid Central Odontogenic Fibroma with Giant Cell Granuloma like Lesion: A Report of Three Additional Cases and Review of the Literature

Central odontogenic fibroma (COF) is an uncommon intraosseous neoplasm of the gnathic bones which is composed of fibrous connective tissue, with or without calcifications, and variable amounts of inactive odontogenic epithelium. It makes up less than 5% of odontogenic tumors and is more commonly seen in females. Central giant cell granuloma (CGCG) is a locally destructive but benign lesion of the jaws containing osteoclast-like multinucleated giant cells in a fibrovascular stroma. CGCG makes up approximately 10% of all benign jaw tumors and typically occurs in females younger than 30 years of age. A hybrid lesion with histologic features of both COF and CGCG is very rare and was first described in 1992. To date, fewer than 50 cases of this lesion have been reported. In this study, we present three additional cases of COF developing in conjunction with giant cell granuloma-like lesion, as well as provide a comprehensive literature review. Two of the lesions presented in our study were located in the posterior mandible and one occurred in the anterior mandible. Buccal and/or lingual expansion was noted in two patients and no recurrence was reported. Histologically, all three lesions demonstrated a blend of odontogenic epithelial islands with numerous multinucleated giant cells in a highly cellular connective tissue stroma. Immunohistochemical staining with CK19 and CD68 highlighted the odontogenic epithelium and multinucleated giant cells respectively. The precise nature of these hybrid lesions remains obscure and additional molecular studies may be of help in understanding their pathogenesis.

Improvement of Giant Cell Lesions of the Jaw Treated With High and Low Doses of Denosumab: A Case Series

Giant cell tumors (GCTs) and central giant cell granulomas (CGCGs) are aggressive lesions that appear in the jaw. These lesions occur in the second and third decades of life and often arise in the mandible. Clinical manifestations of these lesions vary from asymptomatic to symptomatic tooth displacement with cortical perforation. GCTs, which are characterized by multinucleated osteoclast-type giant cells that express receptor activator of nuclear factor-κB (RANK) ligand, rarely present in the jaw and have overlapping histopathologic features with CGCGs, which are composed of fibroblastic stromal cell lesions. GCTs and CGCGs have overlying histopathologic features that make distinction between the two challenging. There is a real controversy as to whether giant cell tumors and central giant cell granulomas are in fact, one and the same lesion. The majority of GCTs occur in the long bone, with surgery being the typical therapeutic option. Denosumab as a treatment modality is a fairly new concept that has been used effectively in GCTs affecting long bones. There is less experience, however, with its use for jaw lesions. This seven-case series describes the effective use of both low-dose and high-dose denosumab in the treatment of GCTs and CGCGs affecting the jaw and special dosing considerations for younger patients who present with disease. © 2017 The Authors. JBMR Plus Published by Wiley Periodicals, Inc. on behalf of the American Society for Bone and Mineral Research.

Odontogenic myxoma: A review with report of an uncommon case with recurrence in the mandible of a teenage male

We describe a 13-year-old boy with recurrence of an odontogenic myxoma of the mandible. We review the existing published literature on the lesion, emphasizing the similarities and differences among lesions in the differential diagnosis. Odontogenic myxoma is an uncommon benign tumor that mainly affects the mandible, with a peak incidence in the second to fourth decades of life and predilection for the female sex. Clinical, radiological, and histopathological features should be considered when making a diagnosis. Several of these characteristics overlap with those of other benign and some malignant tumors. Odontogenic myxoma is known for recurrence. The treatment plan should consider the age and sex of the patient and the site and size of the lesion. Reconstructive surgery may be required, but should be delayed until after an adequate follow-up to rule out recurrence.

Diagnosing the most common odontogenic cystic and osseous lesions of the jaws for the practicing pathologist

Odontogenic cysts and osseous lesions are often seen as challenging diagnostic lesions but the majority of them are easily classified. This article outlines the diagnostic features required for separating the most common of odontogenic cysts and select osseous lesions of the jaws. Clinical and radiographic findings of these jaw lesions often lead to a differential diagnosis that only the histologic findings will clarify. Dentigerous cyst, keratocystic odontogenic tumor, and certain ameloblastomas that have cystic change, may have identical radiographic findings, with only separation by their specific histologic features leading to the significantly different treatments required for each. Conversely, some cystic lesions can appear histologically identical and cannot be diagnosed without the radiographic findings. Certain osseous lesions of the jaws are particularly problematic for diagnosis without the appropriate radiographic findings, and the diagnosis should probably not be attempted on the histologic findings alone. This article will integrate the necessary clinical, radiographic, and histologic findings required to address the most common odontogenic lesions.