Maxillofacial Bone Involvement in Fibro-Osseous Lesions: Emphasizing the Significance of Differential Diagnosis.

The World Health Organization's (WHO) 2022 update on the classification of odontogenic and maxillofacial bone tumors has revolutionized diagnostic and treatment paradigms by integrating novel molecular insights. Fibro-osseous lesions of the maxillo-facial bones constitute a heterogeneous group encompassing fibrous dysplasia, Psammomatoid Ossifying Fibroma (PSOF), Juvenile Trabecular Ossifying Fibroma (JTOF), and other variants. Despite histological similarities, their distinct clinical manifestations and prognostic implications mandate precise differentiation. The intricacies of diagnosing fibro-osseous lesions pose challenges for pathologists, maxillofacial surgeons, dentists and oral surgeons, underscoring the importance of a systematic approach to ensure optimal patient management. Herein, we present two cases, fibrous dysplasia and Cemento-Ossifying Fibroma, detailing their clinical encounters and management strategies. Both patients provided informed consent for publishing their data and images, adhering to ethical guidelines.

Ossifying fibroma of the maxilla: A case report with literature review.

Ossifying fibroma is a benign fibro-osseous lesion arising from the periodontal ligament cells. The lesion may progressively enlarge with the mass affecting the mandible or maxilla, resulting in facial deformities and tooth displacement despite its benign nature. Here, we presented a case of an 18-year-old female with ossifying fibroma in the maxilla extending to the maxillary sinus, infraorbital area, and skull base, resulting in considerable facial asymmetry. Since the primary treatment of ossifying fibroma is surgical resection, it is essential to determine the areas where the lesion has expanded, where a 3-dimensional computed tomography scan could play a critical role in providing such information. A complete surgical excision and histopathologic examination in treating this patient are crucial, made possible by a meticulous preoperative radio imaging technique.

Comprehensive Genomic Analysis of Cemento-Ossifying Fibroma.

Cemento-ossifying fibroma (COF) of the jaws is currently classified as a benign mesenchymal odontogenic tumor, and only targeted approaches have been used to assess its genetic alterations. A minimal proportion of COFs harbor CDC73 somatic mutations, and copy number alterations (CNAs) involving chromosomes 7 and 12 have recently been reported in a small proportion of cases. However, the genetic background of COFs remains obscure. We used a combination of whole-exome sequencing and RNA sequencing to assess somatic mutations, fusion transcripts, and CNAs in a cohort of 12 freshly collected COFs. No recurrent fusions have been identified among the 5 cases successfully analyzed by RNA sequencing, with in-frame fusions being detected in 2 cases (MARS1::GOLT1B and PARG::BMS1 in one case and NCLN::FZR1 and NFIC::SAMD1 in the other case) and no candidate fusions identified for the remaining 3 cases. No recurrent pathogenic mutations were detected in the 11 cases that had undergone whole-exome sequencing. A KRAS p.L19F missense variant was detected in one case, and 2 CDC73 deletions were detected in another case. The other variants were of uncertain significance and included variants in PC, ACTB, DOK6, HACE1, and COL1A2 and previously unreported variants in PTPN14, ATP5F1C, APOBEC1, HDAC5, ATF7IP, PARP2, and ACTR3B. The affected genes do not clearly converge on any signaling pathway. CNAs were detected in 5/11 cases (45%), with copy gains involving chromosome 12 occurring in 3/11 cases (27%). In conclusion, no recurrent fusions or pathogenic variants have been detected in the present COF cohort, with copy gains involving chromosome 12 occurring in 27% of cases.

Clínica, epidemiología e imagenología del fibroma osificante y la displasia fibrosa del territorio cráneo-maxilofacial: revisión narrativa / Clinical, epidemiology and imaging of ossifiying fibroma and fibrous dysplasia of the cranio-maxillofacial territory: narrative review

Introducción: El fibroma osificante (FO) y la displasia fibrosa (DF) tienen características imagenológicas e histopatológicas similares que dificultan el diagnóstico diferencial. El propósito de la presente revisión narrativa es analizar las características clínicas, epidemiológicas e imagenológicas del FO y la DF, y evaluar la relación entre las características imagenológicas y las variantes histopatológicas del FO, en reportes y series de casos publicados.Materiales y métodos:Se realizó una búsqueda de reportes y series de casos de FO y DF entre 2017-2021 en PubMed, Scopus y Web of Science. Los casos debían tener suficiente información clínica, epidemiológica, histopatológica e imagenológica.Resultados:Se incluyeron 23 artículos con 25 lesiones: 17 FO y 8 DF. El tiempo de evolución de DF es más prolongado que FO. FO se ubica con mayor tendencia en complejo osteomeatal en comparación con DF. Sólo FO presentó alteraciones en piel, radiolucidez/hipodensidad periférica, perforación ósea y rizalisis externa, además, tuvo mayor tendencia al avance a espacios anatómicos adyacentes y a generar asimetría facial y/o craneal. FO psammomatoide y FO trabecular comparten patrones imagenológicos y tienen límites definidos corticalizados. FO convencional tuvo mayor tendencia a perforar corticales. DF puede tener límites mal definidos y definidos corticalizados. El FO mostró características imagenológicas de mayor agresividad que la DF.Conclusiones:La histología e imagenología por sí solas no son decisivas en el diagnóstico de FO y DF. Es imprescindible considerar conjuntamente clínica, imagenología e histopatología, enfatizando en las características que orienten el diagnóstico diferencial.(AU)

Introduction: Ossifying fibroma (OF) and fibrous dysplasia (FD) have similar imaging and histopathological characteristics, which make differential diagnosis difficult. The aim of this narrative review was to analyze the clinical, epidemiological and imaging characteristics of OF and FD, as well as to evaluate the relationship between imaging characteristics and histopathologic variants of OF, in reports and case series published.Materials and methods:A search of reports and case series of OF and FD between 2017-2021 in PubMed, Scopus and Web of Science was performed. The cases had to have enough clinical, epidemiological, histopathological and imaging information.Results:23 articles with 25 lesions were included: 17 OF and 8 FD. FD had a longer time of evolution than OF. OF is more likely to be in osteomeatal complex compared to FD. Only OF had skin alterations, peripheral radiolucency/hypodensity, bone perforation and external root resorption, in addition, it had a greater tendency to advance to adjacent anatomical spaces and generate facial and/or cranial asymmetry. Psammomatoid OF and trabecular OF share imaging patterns and have defined and corticated margins. Conventional OF had a greater tendency to cortical perforation. DF can have ill-defined and defined and corticated margins. OF has imaging characteristics of greater aggressiveness than FD.Conclusion:Histology and imaging alone are not decisive in OF and FD diagnosis. It is essential to consider clinical, imaging and histopathological evaluations as a whole, emphasizing in the characteristics that guide the differential diagnosis.(AU)

Radicular Cyst: A Cystic Lesion Involving the Hard Palate.

A radicular cyst, also known as a periapical cyst or root end cyst, is a type of odontogenic cyst that is typically associated with permanent teeth. The radicular cyst usually is associated with maxillary central incisors followed by mandibular first molars. It occurs as a result of bacterial infection and pulpal necrosis which leads to inflammatory stimulation of the epithelial cell rests of Malassez along the periodontal ligament area of the tooth. Most cases of the radicular cyst are asymptomatic and they are diagnosed accidentally during routine radiographic examination. This article presents a case report of a 42-year-old male with an apical periodontal cyst associated with the maxillary anterior region. Early diagnosis and treatment planning is necessary. This article signifies the role of the surgeon in the early diagnosis and treatment plan of the cyst.

Desmoplastic Ameloblastoma-A Case Report.

Desmoplastic ameloblastoma (DA) is a rare variant of conventional ameloblastoma. It accounts for only 4%-13% of all ameloblastomas. DA was included in the World Health Organization Classification of Head and Neck Tumors (WHO-2005) as a variant of ameloblastoma with specific clinical, imaging, and histological features. The desmoplastic variant of ameloblastoma usually appears in the anterior and premolar regions as a mixed radiolucent and radiopaque lesion, sometimes resembling a benign fibro-osseous lesion.Ameloblastoma is a locally aggressive tumor that may cause recurrence and in rare cases, malignant transformation with repeated postsurgical recurrences. In this paper, we present a case of a 28-year-old female with swelling in the left upper jaw, a biopsy of which turned out to be DA.

Cemento-Osseous Dysplasia of the Jaw: Demographic and Clinical Analysis of 191 New Cases.

Cemento-osseous dysplasia (COD) is a form of benign fibro-osseous lesion of the jaw. We sought to evaluate the demographic and clinical presentations of COD by collecting and analyzing the demographic, clinical, radiographic, and pathologic data of COD diagnosed in our institution from 2017 to 2022. Over this six-year period, the records of 191 patients with COD were reviewed. Most patients were African American and female. Eighty-five patients were diagnosed with florid COD (FLCOD), 63 with periapical COD (PCOD), and 43 with focal COD (FCOD). Twenty-eight (14.7%) patients presented symptoms. The most common symptom was pain. All the symptomatic cases of COD that were histopathologically diagnosed were osteomyelitis in the setting of COD. Symptomatic patients were older (mean of 61.3 years) than the asymptomatic patients (mean of 51.2 years). Due to the radiographic appearance of a radiolucency or a mixture of radiolucency and radiopacity, forty-five asymptomatic patients were biopsied. Most of the asymptomatic patients biopsied were patients with FCOD (n = 19, 54.3%), followed by PCOD (n = 16, 25.8%), and FLCOD (n = 10, 15.2%). FLCOD is the most common form of COD to present with symptoms. Due to the significant overlap in clinical and radiographic presentation with other entities, FCOD and PCOD remain a diagnostic challenge to dentists. In conclusion, we analyzed the demographic and clinical features of 191 new cases of COD, which reaffirms that cemento-osseous dysplasia is a condition that primarily affects middle-aged females of African descent and occurs more frequently in the mandible.

Cemento-osseous dysplasia is caused by RAS-MAPK activation.

Cemento-osseous dysplasia (COD) belongs to the spectrum of benign fibro-osseous lesions occurring exclusively in the tooth-bearing areas of the jaws. Depending on site and extent of involvement, periapical, focal and florid subtypes can be distinguished that share an identical histomorphology. Most cases are asymptomatic and follow a self-limited course requiring no specific treatment. Over time, lesions progressively mineralise while the cellularity decreases. However, the molecular pathogenesis of COD, has not yet been explored. We analysed a series of 31 COD samples by targeted sequencing and detected pathogenic hotspot mutations involving the RAS-MAPK signalling pathway in 5/18 evaluable cases (28%). The mutations were found in the BRAF, HRAS, KRAS, NRAS, and FGFR3 genes. Our findings suggest that COD is driven by RAS-MAPK activation; however, the mechanism underlying the spontaneous growth arrest typically occuring in most of the lesions remains elusive.

Fibrocartilaginous mesenchymoma of pelvis-a potential diagnostic pitfall.

Fibrocartilaginous mesenchymoma (FM) is a rare bone tumor mimicking other fibrocartilaginous lesions on imaging and histologically. Hence, it is difficult to diagnose this entity especially on small biopsies. In this article, we report a case of FM mimicking desmoplastic fibroma on biopsy. A 36-year-old male presented with pain in the left hip. Imaging showed a large expansile lytic lesion involving the acetabulum and pubis. The differential diagnosis was suggestive of giant cell tumor, aneurysmal bone cyst, intraosseous desmoplastic fibroma, and chondrosarcoma. Biopsy revealed a low-grade spindle cell lesion with no evidence of osteoid or chondroid matrix. The lack of cartilaginous nodules in the biopsy prompted a preoperative diagnosis of desmoplastic fibroma. The excised mass showed bland spindle cell proliferation, benign cartilage nodules, and epiphyseal plate-like enchondral ossification suggestive of fibrocartilaginous mesenchymoma. Negative immunostaining for SATB2, CDK4, and MDM2 ruled out low-grade central osteosarcoma. Though GNAS mutations were not performed in this case, rimming of the bony trabeculae at the periphery of the epiphyseal growth plate-like cartilaginous nodule ruled out fibrous dysplasia. The absence of cartilaginous component misleads the diagnosis preoperatively in small biopsies.

Fibro-Osseous Lesion of the Nose and Paranasal Sinus: A Retrospective Study With Literature Review.

Background Fibro-osseous (FO) lesions are slow-growing benign lesions in the paranasal sinuses. They include osteomas, fibrous dysplasia (FD), and ossifying fibro-ma (OF). Fibro-osseous (FO) lesions are frequently asymptomatic, and they are incidentally found on imaging. They are characterized by different histological, radiological, and clinical variants. Depending on symptoms, size, location, and extension, the treatment strategy varies significantly for these lesions. Objective We aim to compare the age, onset, gender, clinical presentation, postoperative improvement, and complications of a fibro-osseous lesion in the paranasal sinuses. Methods A retrospective analysis was done targeting patients diagnosed with benign fibro-osseous (FO) lesions, and the incidence among 403 patients who underwent functional endoscopic sinus surgery (FESS) at Aseer Central Hospital, Kingdom of Saudi Arabia, was reviewed from January 2013 to January 2022. Results A total of seven patients were found; five patients were diagnosed with osteoma, and two were diagnosed with fibrous dysplasia. There were no ossifying fibroma cases. The patients' mean age was 25.5 ± 12.9 years old. Four (57.1%) patients were males, and three (42.9%) were females, with a male/female ratio of 1.25:1. The most common locations were the frontal sinus and ethmoid sinus, and the two cases of fibrous dysplasia involved almost all facial bones. The endonasal endoscopic approach was chosen to treat all seven patients. Conclusions There are differences in the onset age, location, and complications postoperatively among osteoma and fibrous dysplasia patients. Osteoma most commonly occurs in the frontal sinus, while fibrous dysplasia involved all facial bones in our study. Endoscopic surgery is currently the primary strategy for treatment.

Implant placement in a focal cemento-osseous dysplasia: A modified protocol with a successful outcome.

Cemento-osseous dysplasia (COD) is defined as a condition in which normal bone is replaced by fibrous connective tissue and cementum-like deposits. It is generally asymptomatic and occurs mostly in female patients. Radiologically, it appears as an opaque, lobulated mass. When facing such lesions, it is advised to avoid performing any surgical procedures due to the decreased vascularization and healing potential. The main reported complications being poor healing, sequestrum formation, risk of infection, and fracture of the jaw. Treating posterior mandibular edentulism in presence of a COD can be a challenging situation especially when the patient requires an implant-supported fixed rehabilitation. The aim of this paper is to describe a three-stage modified protocol for implant placement in a compromised site presenting a focal cemento-osseous dysplasia.

Ossifying Fibroma of Non-odontogenic Origin: A Fibro-osseous Lesion in the Craniofacial Skeleton to be (Re-)considered.

In the cranio-facial skeleton, a heterogeneous group of well characterized fibro-osseous lesions can be distinguished. Whereas fibrous dysplasia can affect any skeletal bone, ossifying fibroma and cemento-osseous dysplasia exclusively develop in the cranio-facial region, with most subtypes restricted to the tooth bearing areas of the jaws. Herein we present a series of 20 fibro-osseous lesions that developed mostly in the frontal bone and in the mandible, presenting as expansile intramedullary tumors with a unique histologic appearance and an indolent clinical course. We provide evidence that these tumors are distinct from the categories included in the WHO classification and are therefore currently unclassifiable. The definition of cemento-ossifying fibroma as an odontogenic neoplasm developing only in close proximity to teeth should be re-considered and incorporate also extragnathic lesions as shown here.

Cystic degeneration in cemento-ossifying fibroma: Diagnosis challenge and conservative management - Case report.

INTRODUCTION AND IMPORTANCE: Cemento ossifying fibroma (COF) is an encapsulated lesion that is often found in the mandible of middle-aged females. Cystic degeneration may be associated to several osseous lesion. This particular presentation is not well documented in the jaws. CASE PRESENTATION: Patient presented was referred to oral surgery department for abnormal radiolucency in the right mandible on panoramic X-ray. The patient did not have any specific medical history and reported painful areas in right mandibular region. During diagnosis assessment, ameloblastoma was first considered due to the presence of cystic lesion clusters. But the mixed image in previous X-ray pointed to a fibro-osseous with a change in pathogenesis pathway. Diagnosis buildup was based on previous radiographs, incisional biopsy was proposed to identify the histopathological feature of the lesion before proceeding to further investigation (CBCT) or treatments (decompression or enucleation). COF of the jaws associated to non-specific cystic changes was the histopathological diagnosis. Delay in treatment showed an unexpected outcome with good clinical and bone healing. CLINICAL DISCUSSION AND CONCLUSION: This case shows the importance of previous radiographs, when available, in diagnosis buildup. The fibro-osseous lesion with cystic change may show a good biological response with conservative management. A clinical and radiological surveillance after a conservative treatment may be a better option in treatment of these lesions.

Concurrent dentigerous cyst with ossifying fibroma of the mandible.

Dentigerous cyst (DC) and ossifying fibroma (OF) are intraosseous lesions of the jaw. Both are varied pathological entities with a wide spectrum of clinical and histological features along with distinct treatment plan and prognosis. While OF comes under fibro-osseous lesions of the jaws, DC is a developmental odontogenic cyst which is formed by the accumulation of fluid between reduced enamel epithelium and enamel or between layers of the enamel organ. This case report presents a rare display of two distinct pathologies synchronously and aims to discuss the possible histogenesis for the same.

Cemento-Ossifying Fibroma of Upper Lip in a Female Child.

Cemento-ossifying fibroma (COF) is a benign tumor classified under fibro-osseous lesions characterized by the proliferation of fibrous tissue associated with the presence of osteoid or cementicle-like masses. COF of bony origin is highly neoplastic in nature compared to their soft tissue counterparts which are relatively rare. The authors here present a case report of COF arising from the left upper lip in a 10-year-old female patient. The lesion was initially asymptomatic, slow-growing in nature, and later turned painful over a period of eight months. A medical CT was taken to elicit a calcified mass seen at the left subcutaneous plane of the upper lip. The lesion was surgically treated by complete excision under local anaesthesia and sutured. Follow-up was done for a period of one year to assess for recurrence which was not evident in this case. This case report, being a peculiar case of COF arising from the soft tissue of the upper lip, describes the clinical presentation, diagnostic imaging, histopathological evidence, and brief surgical management of the lesion.

Spheno-orbital juvenile psammomatoid ossifying fibroma: a case report and literature review.

Ossifying fibroma (OF) is an uncommon benign fibro-osseous lesion. Based on its clinical, morphological, and radiological features, OF is further divided into cemento-ossifying fibroma (COF), juvenile psammomatoid ossifying fibroma (JPOF), and juvenile trabecular ossifying fibroma (JTOF). JPOF rarely involves the cranial base, with limited reports published on spheno-orbital JPOF. In this paper, we report a case of JPOF of the greater wing of the sphenoid bone and lateral orbital wall in an 11-year-old child and show a surgical video. Although rare, JPOF should be considered in the differential diagnosis of fibro-osseous lesions of the spheno-orbital region.

Calcifying Pseudoneoplasm of the Neuraxis Involving the Posterior Skull Base: A Case Report and Literature Review.

Calcifying pseudoneoplasm of the neuraxis is an uncommon, nonneoplastic fibro-osseous lesion of the central nervous system. At the time of this report, at least 150 cases have been reported in the literature. Because of the rarity of this lesion, it is often diagnostically challenging for radiologists and pathologists alike. In this article, we present a case of a 44-year-old woman with a 5.8-cm intracranial/skull base calcifying pseudoneoplasm of the neuraxis that was concerning for osteosarcoma on initial frozen section. Permanent sections revealed bone and fibrous stroma, calcifications, and nests of histiocytes with granuloma formation. Scattered, focally dense inflammatory foci and spindled cells outlining abundant large nodules of chondromyxoid matrix were also present. In this case report, we also reviewed recent literature for clinical presentations, radiologic findings, and histologic differential diagnoses. Familiarity with this lesion is important to avoid misdiagnosis leading to unnecessary and potentially harmful treatment.

A clinicopathologic analysis of 135 cases of cemento-osseous dysplasia: To operate or not to operate?

PURPOSE: The aim of this retrospective study was to investigate the characteristics of cemento-osseous dysplasia (COD) lesions for devising a clinical algorithm to help management decisions, specifically discussing the need for a possible surgical intervention versus solely follow-up. MATERIALS AND METHODS: One hundred thirty-five subjects were thus identified having previously diagnosed and treated for COD from the archives of the pathology in between 2005-2015. These were then re-evaluated. Demographic features, radiographic and histopathologic findings were assessed. RESULTS: The most frequent variant was the focal type (n=83), and the mandible (n=131) was predominantly affected jaw bone. Female predilection was evident for all subtypes. Almost half of the lesions (n=72) presented with mixed radiolucent and radiopaque appearances in radiography at the time of the biopsy. Cementicles/psammoma body-like calcifications and trabecular pattern were the most common hard tissue appearances. CONCLUSION: COD lesions are non-neoplastic fibro-osseous lesions which can exhibit similar histopathologic and radiologic features with other bone lesions. Ideally, these lesions should be clinically identified and followed-up. Considering the possible complications, a thorough knowledge of these lesions and their differentials is essential in order to avoid unnecessary surgical interventions.

Fibro-osseous Lesions of Paranasal Sinus and Craniofacial Region: A Retrospective Study of 282 Cases.

OBJECTIVES: To compare the clinical characteristics of osteoma, ossifying fibroma (OF) and fibrous dysplasia (FD) in the paranasal sinus and craniofacial regions. METHODS: Totally 282 patients (112 males, 170 females) with osteoma (161), OF (44), and FD (77) involving the paranasal sinus, skull base and orbit treated surgically from January 2012 to August 2018 were analyzed retrospectively. RESULTS: For osteoma, OF and FD, the onset ages were 40.3 (6-75), 24.5 (5-62), and 15 (1-63) years, and the most common locations were ethmoid sinus (49.7%), maxilla (36.4%) and maxilla (49.4%), respectively. There were significant differences of the preoperative serum alkaline phosphatase (ALP) levels between patients with osteoma (65 [25,184] U/L), OF (85.5 [41,474] U/L), and FD (104 [39,362] U/L) (Z = 44.9, P < .05). The ALP levels of OF and FD patients were comparable between monostotic and polyostotic lesions (P > .05). The recurrent rates of osteoma, OF, and FD were 0%, 13.6%, and 15.6%, respectively. The recurrent OF cases had significantly higher ALP level than the primary ones (283.5 [108,474] U/L vs. 76 [41,348] U/L, U = 14, P < .05). CONCLUSION: There are differences in the onset age, location, and recurrence rate among osteoma, OF and FD involving the paranasal sinus and craniofacial region. Osteoma most commonly occurs in the ethmoid sinus, while OF and FD involve the maxilla most and are more likely to involve the orbit and the skull base, respectively. Endoscopic surgery is currently the main method for treatment, but individualized treatment regimen should be developed for patients. LEVEL OF EVIDENCE: IV Laryngoscope, 131:E1-E7, 2021.