Ossifying fibroma of the jaws: report of two cases and literature review

CT-based radiomics analysis of different machine learning models for differentiating gnathic fibrous dysplasia and ossifying fibroma

OBJECTIVE

In this study, our aim was to develop and validate the effectiveness of diverse radiomic models for distinguishing between gnathic fibrous dysplasia (FD) and ossifying fibroma (OF) before surgery.

MATERIALS AND METHODS

We enrolled 220 patients with confirmed FD or OF. We extracted radiomic features from nonenhanced CT images. Following dimensionality reduction and feature selection, we constructed radiomic models using logistic regression, support vector machine, random forest, light gradient boosting machine, and eXtreme gradient boosting. We then identified the best radiomic model using receiver operating characteristic (ROC) curve analysis. After combining radiomics features with clinical features, we developed a comprehensive model. ROC curve and decision curve analysis (DCA) demonstrated the models' robustness and clinical value.

RESULTS

We extracted 1834 radiomic features from CT images, reduced them to eight valuable features, and achieved high predictive efficiency, with area under curves (AUC) exceeding 0.95 for all the models. Ultimately, our combined model, which integrates radiomic and clinical data, displayed superior discriminatory ability (AUC: training cohort 0.970; test cohort 0.967). DCA highlighted its optimal clinical efficacy.

CONCLUSION

Our combined model effectively differentiates between FD and OF, offering a noninvasive and efficient approach to clinical decision-making.

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.

A Painless Bump: A Case Report of Cemento-Ossifying Fibroma of the Anterior Maxilla

Cemento-ossifying fibroma (COF) is a benign odontogenic neoplasm. It is considered an ossifying fibroma with traces of interspersed cementum fragments. Here we present a case report of the occurrence of COF in the maxillary anterior region of an elderly woman. A 61-year-old female reported with a painless, progressive, slow-growing swelling on the upper front jaw region for the past five years. A single, localized, swelling on the anterior region of the maxilla which was non-tender and bony hard in consistency. Radiological examination consisting of orthopantomagram (OPG) and cone-beam computed tomography (CBCT) revealed increased thickness of bone over frontal, parietal and maxilla with alteration of trabecular pattern - cotton wool/ground glass. Serum alkaline phosphatase level was found to be 865 U/l, however, serum calcium level and other routine blood investigations (hemogram) were within normal limits. The above radiological and laboratory findings are more in favour of primary bone pathology and with a biopsy later correlating with histopathological findings; it was diagnosed as COF. Under conscious sedation, surgical excision of the bony mass was done along with extraction of associated teeth. The patient is currently on regular follow-up and planning for a dental prosthesis is in progress.

Tru-cut needle biopsy: A novel approach in the diagnosis of solid oral pathologies

Nowadays, new biopsy techniques such as fine and wide needles are now employed instead of invasive biopsy techniques. Compared to open biopsy, true-cut needle biopsy has a number of advantages. It's quick and simple to do, can be done in an outpatient department, avoids incisions into previously irradiated skin, and has few risks. In order to examine malignant and benign tumours, there had been a debate in the past century on the utilisation and efficiency of tru-cut biopsy over Fine needle aspiration cytology (FNAC) and surgical biopsy in solid tumours. A non-odontogenic tumour that occurs in jaws, also classified as a fibro-osseous lesion of the jaw, is Cemento-Ossifying Fibroma. Clinically, these lesions occur as gradually growing, reaching an enormous size if not treated. In this article, a case of cemento-ossifying fibroma noticed in the maxilla with facial swelling is discussed and the diagnosis was done using a tru-cut needle biopsy.

Endoscopic Transnasal Management of Giant Paediatric Sinonasal Ossifying Fibroma

The ossifying fibroma is a rare fibro-osseous benign lesion of bone in the head and neck region. The mandible is the most common site reported followed by maxilla and other bones of the skull. A paediatric male presented with protrusion of the right eyeball for one-month duration. Further evaluation by diagnostic nasal endoscopy revealed a smooth mass confined to the superior and middle meatus on the right side. Computed tomography of paranasal sinus showed a large heterogenous bony lesion involving the ethmoid and sphenoid sinus and extending laterally into the orbit and superiorly into anterior skull base. Endoscopic biopsy was suggestive of ossifying fibroma. Transnasal endoscopic excision of the lesion was done and the patient is currently on follow-up. This case is reported for the rarity of presentation and the difficulties in management.

Atypical Presentation of Peripheral Ossifying Fibroma in the Mandible

Peripheral ossifying fibroma (POF) is a localized reactive enlargement of the gingiva often associated with the papilla and originate from underneath the periodontium. POF occurs predominantly in females, especially in the anterior maxillary region of young adults. The histopathological examination provides a confirmatory diagnosis of such lesions due to their heterogeneous clinical and radiographic characteristics. This case report describes an atypical presentation of POF in the anterior mandible in an adult male patient. Treatment consisted of complete surgical excision and gingival curettage resulting in uneventful healing during the postoperative follow-up period.

Anatomical and volumetric analysis of fibro-osseous lesions of the craniofacial skeleton

PURPOSE

Our study aimed to provide volumetric data relating to fibro-osseous lesions of the craniofacial skeleton, in order to highlight risk factors due to the different entities, and to guide clinical decisions for jeopardized patients.

METHODS

Volumetric measurements of osteomas and ossifying fibromas were performed by applying the open-source software ITK-Snap to cone-beam computed tomography images. DICOM datasets were imported, identified, and delineated using semiautomatic segmentation; this was then verified using manual segmentation. The volumes of the lesions were computed automatically in cubic millimeters using the program. For statistical investigations, descriptive statistics and independent Student t-tests were performed. Additionally, Pearson's correlation was applied as a bivariate analysis. Values of p < 0.05 were considered significant.

RESULTS

45 patients (11 male and 34 female) were included in this study. The mean volumes were 10.02 ± 18.79 cm³ for osteomas and 4.80 ± 5.71 cm³ for ossifying fibromas (p = 0.016). Males (12.81 ± 20.38 cm³) presented significantly larger volumes than females (5.43 ± 10.32 cm³) (p = 0.042). With regard to shape, morphology, and affection of surrounding anatomical structures, irregular shape (p = 0.001; p = 0.037), multilocular morphology (p = 0.001; p = 0.037), nerve affection (p = 0.001; p = 0.002), tooth affection (p = 0.001; p = 0.594), cortical bone exceedance (p = 0.033; p = 0.001), and clinically visible symptoms (p = 0.004; p = 0.001) were statistically significantly associated with a larger volume of both entities.

CONCLUSION

Volumetric analysis revealed that osteomas significantly exceeded the mean size of ossifying fibromas, supporting the argument that special attention should be paid to this entity. In cases of difficult histopathological examination, lesions with irregular shape, multilocular morphology, nerve and tooth affection, cortical bone exceedance, and clinically visible symptoms should be considered for close clinico-radiological follow-up, irrespective of the entity.

Copy number alteration profiling facilitates differential diagnosis between ossifying fibroma and fibrous dysplasia of the jaws

Ossifying fibroma (OF) and fibrous dysplasia (FD) are two fibro-osseous lesions with overlapping clinicopathological features, making diagnosis challenging. In this study, we applied a whole-genome shallow sequencing approach to facilitate differential diagnosis via precise profiling of copy number alterations (CNAs) using minute amounts of DNA extracted from morphologically correlated microdissected tissue samples. Freshly frozen tissue specimens from OF (n = 29) and FD (n = 28) patients were obtained for analysis. Lesion fibrous tissues and surrounding normal tissues were obtained by laser capture microdissection (LCM), with ~30–50 cells (5 000–10 000 µm²) per sample. We found that the rate of recurrent CNAs in OF cases was much higher (44.8%, 13 of 29) than that in FD cases (3.6%, 1 of 28). Sixty-nine percent (9 of 13) of the CNA-containing OF cases involved segmental amplifications and deletions on Chrs 7 and 12. We also identified eight CNA-associated genes (HILPDA, CALD1, C1GALT1, MICALL2, PHF14, AIMP2, MDM2, and CDK4) with amplified expression, which was consistent with the copy number changes. We further confirmed a jaw lesion with a previous uncertain diagnosis due to its ambiguous morphological features and the absence of GNAS mutation as OF based on the typical Chr 12 amplification pattern in its CNA profile. Moreover, analysis of a set of longitudinal samples collected from an individual with a cellular lesion in suspicion of OF at the first surgery, recurrence and the latest malignant transformation revealed identical CNA patterns at the three time points, suggesting that copy number profiling can be used as an important tool to identify borderline lesions or lesions with malignant potential. Overall, CNA profiling of fibro-osseous lesions can greatly improve differential diagnosis between OF and FD and help predict disease progression.

Piezoelectric-Assisted Removal of a Mandibular Cementoossifying Fibroma: An Innovative Technique

Diagnosis of cementoossifying fibroma is oriented by the clinical and radiological aspects of the lesion. Histology confirms the diagnosis. Treatment is surgical with enucleation-resection depending on the lesion size or wider resection with bone reconstruction in cases of large fibromas. The use of piezoelectric bone surgery is associated with low surgical trauma, exceptional precision, and fast healing response. It also allows easy performance of complex osteotomy and reduces the necessary dimensions of mucoperiosteal dissection. The purpose of the present article was to present the advantages of piezoelectric-assisted surgical removal of a cementoosseous fibroma of the mandible and to provide a precise description of the procedure using atraumatic surgery.

Ossifying fibroma in the maxilla and orbital floor: report of an uncommon case

Benign fibro-osseous lesions occur when normal bone is replaced by cellular fibrous connective tissue and mineralized structures. One rare type of these lesions is the ossifying fibroma (OF). The aim of this study is to report an unusual case of OF in a 57-year-old female. Physical examination showed facial asymmetry without any tenderness, fluctuation, ocular pain, or ophthalmoplegia. Imaging exams revealed a solid mass involving the left maxilla and orbital floor. Surgical resection was performed without any complications or sequelae, and the histopathological results confirmed OF. Although recurrence is rare in this condition, the patient remains under follow-up.

A large maxillary cemento-ossifying fibroma superimposed with solitary bone cyst documented over 18 years: A case report

INTRODUCTION

Cemento-ossifying fibromas are rare, benign lesions of the head and neck regions. The origin of these lesions can be traced to the periodontal ligament, because its cells are able to form cement, lamellar bone, or fibrous tissue.

CASE PRESENTATION

A rare case report of a young Caucasian female with a COF is described including follow-ups. She remained untreated for several years despite early radiographic findings of the lesion without a definitive diagnosis. The patient ultimately underwent radical surgery and the whole lesion was removed. The subsequent histological examination confirmed the clinical diagnosis of a COF. Since then, the patient has been under regular clinical and radiological follow-ups.

DISCUSSION

This rare case report of a COF, documented over 18 years, shows the importance of consecutive therapy after radiologic and clinical findings, as such lesions continue growing and may subsequently lead to severe medical conditions. Therefore, complete surgical resection of COFs is advised to achieve good results in terms of health and recurrence.

CONCLUSION

Long-term follow-up of patients is required as recurrences can occur for up to 10 years following treatment. Well-planned radical and wide surgical resection of these lesions has proven not only to be effective in eliminating the aetiological factors, but can also achieve decent bone regeneration and aesthetic results with almost no deformation in the surgical site.

Ossifying fibroma in the mandibular angle mimicking metastatic clear cell renal cell carcinoma: A case report

RATIONALE

Ossifying fibroma is benign fibro-osseous neoplasm. The authors report a case of ossifying fibroma in the mandibular angle suspected as metastasis of clear cell renal cell carcinoma.

PATIENT CONCERNS

A 74-year-old man presented to the primary hospital complaining of frequent urination. A tumor in the left kidney was detected via an abdominal computed tomography scan. The patient then visited the Department of Urology at our hospital.

DIAGNOSES

According to whole-body imaging examinations, the patient was suspected of having renal cancer with mandibular metastasis. Also, a cystic lesion of the maxilla was revealed.

INTERVENTIONS

Left nephrectomy was performed by urologists, and the patient was diagnosed with clear cell renal cell carcinoma of the left kidney. Approximately 1 month later, resection with a safety margin of the mandibular lesion and removal of the maxillary lesion were performed by oral and maxillofacial surgeons.

OUTCOMES

The patient was diagnosed with ossifying fibroma of the mandible and an odontogenic keratocyst of the maxilla via a histopathological examination. Eighteen months have passed since the operation without clinical and imaging findings associated with recurrence.

LESSONS

Ossifying fibroma in the mandibular angle of elderly patients is extremely rare. Surgeons should consider the possibility of metastasis when osteolytic lesions of the jaw are found in patients with cancer.

Microvessel density and cell proliferation in juvenile ossifying fibroma: A comparative study with central ossifying fibroma

Considered as an aggressive counterpart of central ossifying fibroma (OF), juvenile ossifying fibroma (JOF) is a benign fibro-osseous neoplasm characterized by an unpredictable destructive behavior, elevated morbidity, mutilating treatment and high potential for local recurrences. The aim of this study is to compare the analysis for cell proliferation and vascular markers between JOF and OF. Cell proliferation index was measured by Ki-67 and Mcm-2 expression and microvessel density (MVD) was obtained by the immunoexpression of CD34/CD105. We observed a reduced expression of vascular markers, where MVD for CD34 was significantly higher in JOF than in OF (p = 0.009), but no statistical difference was found for CD105. JOF and OF showed low expression for Ki-67 and Mcm-2 and no difference was noted between both, suggesting that other mechanisms such as anti-apoptotic and/or pro-autophagic pathways or even increased expression of matrix metalloproteinases may be responsible for the aggressiveness of JOF.

Cemento-ossifying fibroma of the jaw

Cemento-ossifying fibroma is a benign growth, considered to originate from the periodontal ligament. It is often encapsulated and predominantly located in the mandible, and presents as a slow-growing lesion, but may cause deformity if left untreated. The definitive diagnosis of these lesions requires integration of its clinical, radiological and histological features. We present a case of cemento-ossifying fibroma in relation to the lower left one-third of the face, and its management.

Benign Jaw Lesions

There are both odontogenic and nonodontogenic benign lesions in the maxilla and mandible. These lesions may have similar imaging features, and the key radiographic features are presented to help the clinician narrow the differential diagnosis and plan patient treatment. Both intraoral and panoramic radiographs and advanced imaging features are useful in assessing the benign lesions of the jaws. The location, margins, internal contents, and effects of the lesions on adjacent structures are important features in diagnosing the lesions.

Ossifying fibroma of the jaws: a clinicopathological case series study

The aim of this study was to assess the clinical, radiographic and microscopic features of a case series of ossifying fibroma (OF) of the jaws. For the study, all cases with OF diagnosis from the files of the Oral Pathology Laboratory, University of Ribeirão Preto, Ribeirão Preto, SP, Brazil, were reviewed. Clinical data were obtained from the patient files and the radiographic features were evaluated in each case. All cases were reviewed microscopically to confirm the diagnosis. Eight cases were identified, 5 in females and 3 in males. The mean age of the patients was 33.7 years and most lesions (7 cases) occurred in the mandible. Radiographically, all lesions appeared as unilocular images and most of them (5 cases) were of mixed type. The mean size of the tumor was 3.1 cm and 3 cases caused displacement of the involved teeth. Microscopically, all cases showed several bone-like mineralized areas, immersed in the cellular connective tissue. From the 8 cases, 5 underwent surgical excision and 1 patient refused treatment. In the remaining 2 cases, this information was not available. In conclusion, OF occurs more commonly in women in the fourth decade of life, frequently as a mixed radiographic image in the mandible. Coherent differential diagnoses are important to guide the most adequate clinical approach. A correlation between clinical, imaginological and histopathological features is the key to establish the correct diagnosis.

Ossifying Fibroma in a Patient With Oculocerebrocutaneous (Delleman) Syndrome

Delleman syndrome is a rare neurocutaneous disorder characterized by congenital anomalies affecting the eye, skin, and central nervous system. This disorder was first raised as a distinct syndromic entity by Delleman and Oorthuys in 1981 under the term "oculocerebrocutaneous syndrome" (OCCS). Since then, fewer than 40 cases have been reported. All cases have been sporadic, and no patient with an abnormal karyotype has been reported. Although the etiology is still unknown, several theories have been advanced. Most of the tissues affected by OCCS are neural crest derivatives, with a striking homogeneity of the tissues and regions involved. It is this recurring craniofacial pattern of OCCS that lends support to the hypothesis that the most probable pathogenesis is a neurocristopathy that interferes with craniofacial morphogenesis. Ossifying fibroma is a destructive, potentially deforming, benign tumor that can occur almost anywhere in the facial skeletion. Some cases of ossifying fibroma have occurred in patientswith underlying neurocutaneous syndromes such as neurofibromatosis, Sturge-Weber syndrome, and encephalocraniocutaneous lipomatosis (ECCL). We report a patient with OCCS who presented with an ossifying fibroma. This has not been reported previously and is noteworthy in that it might be part of a wider phenotypic spectrum of the less common manifestations associated with OCCS.

A swelling of the maxilla: a case report and differential diagnosis

Ossifying fibromas are benign fibro-osseous tumors of mesenchymal origin. Although ossifying fibromas have principally been found in the jaw, they have also been reported in the frontal, ethmoid, sphenoid, and temporal bones, as well as the orbit and anterior cranial fossa. Ossifying fibromas affecting the jaw exhibit variable behaviors ranging from slow growth to occasionally aggressive local destruction. In the present article, we discuss a differential diagnosis considered for maxillary swellings and report a rare case of ossifying fibroma occurring in the maxilla.

Giant central ossifying fibroma of the maxilla presenting with a pus discharging intra-oral sinus

Central ossifying fibroma (COF) is a rare benign fibro-osseous neoplasm which has a predilection for mandible and is encountered in middle aged women. It arises from mesenchymal blast cells of the periodontal ligament, and with a potential to form fibrous tissue, cementum and bone. It is a well circumscribed lesion mainly comprising of fibrous tissue with varying amounts of bone or cementum or osteo-cementum like tissue. We present an uncommon case of COF of the maxilla in a 35-year-old male who presented with a pus discharging sinus in the maxilla. Due to the bizarre size of the lesion we have termed as 'giant' COF. There is extensive facial asymmetry on the right side with obliteration of the maxillary antrum, deviation of the nose and upward displacement of the orbit.

Ossifying fibroma tumor stem cells are maintained by epigenetic regulation of a TSP1/TGF-β/SMAD3 autocrine loop

Abnormal stem cell function makes a known contribution to many malignant tumors, but the role of stem cells in benign tumors is not well understood. Here, we show that ossifying fibroma (OF) contains a stem cell population that resembles mesenchymal stem cells (OFMSCs) and is capable of generating OF-like tumor xenografts. Mechanistically, OFMSCs show enhanced TGF-β signaling that induces aberrant proliferation and deficient osteogenesis via Notch and BMP signaling pathways, respectively. The elevated TGF-β activity is tightly regulated by JHDM1D-mediated epigenetic regulation of thrombospondin-1 (TSP1), forming a JHDM1D/TSP1/TGF-β/SMAD3 autocrine loop. Inhibition of TGF-β signaling in OFMSCs can rescue their abnormal osteogenic differentiation and elevated proliferation rate. Furthermore, chronic activation of TGF-β can convert normal MSCs into OF-like MSCs via establishment of this JHDM1D/TSP1/TGF-β/SMAD3 autocrine loop. These results reveal that epigenetic regulation of TGF-β signaling in MSCs governs the benign tumor phenotype in OF and highlight TGF-β signaling as a candidate therapeutic target.

GNAS mutational analysis in differentiating fibrous dysplasia and ossifying fibroma of the jaw

Differential diagnosis of fibrous dysplasia and ossifying fibroma may often pose problems for pathologists. The purpose of this study was to evaluate the value of mutational analysis of the GNAS gene in differentiating these two conditions. DNA samples from patients with fibrous dysplasia (n=30) and ossifying fibroma (n=21) were collected to analyze the presence of GNAS mutations at exons 8 and 9, the two previously reported hotspot regions, using polymerase chain reaction and direct sequencing. In all, 90% (27/30) of cases with fibrous dysplasia showed missense mutations of codon 201 at exon 8, with a predilection of arginine-to-histidine substitution (p.R201H, 70%) as opposed to arginine-to-cysteine substitution (p.R201C, 30%), whereas no mutation was detected at exon 9. No mutation was found in all 21 cases with ossifying fibroma. In addition, a meta-analysis of previously published reports on GNAS mutations in fibrous dysplasia and ossifying fibroma was performed to substantiate our findings. A total of 24 reports including 307 cases of fibrous dysplasia and 23 cases of ossifying fibroma were reviewed. The overall incidence of GNAS mutations in fibrous dysplasia was 86% (264/307), and the major types of mutations were also R201H (53%) and R201C (45%). No GNAS mutation was detected in all patients with ossifying fibroma. We also reported one case with uncertain diagnosis due to overlapping clinicopathological features of fibrous dysplasia and ossifying fibroma. An R201H mutation was detected in this case, thus confirming a diagnosis of fibrous dysplasia. Taken together, our findings indicate that mutational analysis of GNAS gene is a reliable adjunct to differentiate ossifying fibroma and fibrous dysplasia of the jaws.

Cellular proliferation markers in peripheral and central fibromas: a comparative study

OBJECTIVE

To perform a comparative study of the cellular proliferation in the peripheral and central fibromas.

MATERIAL AND METHODS

Immunohistochemistry for PCNA and the AgNOR technique were performed in 9 cases of peripheral odontogenic fibroma (POF), in 4 cases of odontogenic fibroma (OdF), in 8 cases of peripheral ossifying fibroma (PEOF) and 7 cases of ossifying fibroma (OsF). The Kruskal-Wallis and Mann-Whitney tests were used for the statistical analyses.

RESULTS

Mesenchymal component of the central lesions presented a higher mean number of AgNOR per nucleus and PCNA index than did the peripheral lesions (P≤0.05). The mean number of AgNOR per nucleus in the epithelial component proved to be higher in the OdF than in the POF (P≤0.05). The mesenchymal and epithelial components presented similar mean numbers of AgNOR per nucleus and PCNA index in the OdF, as well as a similar mean number of AgNOR per nucleus in the POF.

CONCLUSIONS

The mesenchymal component may well play a role in the differences between the biological behaviour of the central lesions as compared to the peripheral lesions. Moreover, considering that the epithelial and mesenchymal components in odontogenic fibromas presented a similar proliferation index, more research is warranted to understand the true role of the epithelial components, which are believed to be inactive in nature, as well as in the development and biological behaviour of these lesions.