Two cases of multiple ossifying fibromas in the jaws

Phenotypic Profiling and Molecular Mechanisms in Hyperparathyroidism-jaw Tumor Syndrome

CONTEXT

Hyperparathyroidism-jaw tumor (HPT-JT) syndrome is a heritable form of primary hyperparathyroidism caused by germline inactivating mutations in CDC73 encoding parafibromin and is associated with an increased risk of parathyroid cancer. There is little evidence to guide the management of patients with the disease.

OBJECTIVE

(1) Characterize the natural history of HPT-JT, (2) correlate genotype and histology of parathyroid tumors with parafibromin immunostaining, (3) understand molecular changes downstream to CDC73 loss.

DESIGN

Retrospective study of patients with HPT-JT syndrome (genetically confirmed or affected first-degree relatives). Independent review of uterine tumor from 2 patients and staining for parafibromin on parathyroid tumors from 19 patients (13 adenomas, 6 carcinomas) was performed. RNA-sequencing was performed in 21 parathyroid samples (8 HPT-JT-related adenomas, 6 HPT-JT-related carcinomas, and 7 sporadic carcinomas with wild-type CDC73).

RESULTS

We identified 68 patients from 29 kindreds with HPT-JT with median age at last follow-up of 39 [interquartile range, 29-53] years. A total of 55/68 (81%) developed primary hyperparathyroidism; 17/55 (31%) had parathyroid carcinoma. Twelve of 32 (38%) females developed uterine tumors. Of the 11 patients who had surgical resection for uterine tumors, 12/24 (50%) tumors were rare mixed epithelial mesenchymal polypoid lesions. Four of 68 patients (6%) developed solid kidney tumors; 3/4 had a CDC73 variant at p.M1 residue. Parafibromin staining of parathyroid tumors did not correlate with tumor histology or genotype. RNA-sequencing showed a significant association of HPT-JT-related parathyroid tumors with transmembrane receptor protein tyrosine kinase signaling pathway, mesodermal commitment pathway, and cell-cell adhesion.

CONCLUSIONS

Multiple, recurrent atypical adenomyomatous uterine polyps appear to be enriched in women with HPT-JT and appear characteristic of the disease. Patients with CDC73 variants at p.M1 residue appear predisposed to kidney tumors.

CLINICAL TRIAL NUMBER

NCT04969926.

Molecular and Clinical Spectrum of Primary Hyperparathyroidism

Recent data suggest an increase in the overall incidence of parathyroid disorders, with primary hyperparathyroidism (PHPT) being the most prevalent parathyroid disorder. PHPT is associated with morbidities (fractures, kidney stones, chronic kidney disease) and increased risk of death. The symptoms of PHPT can be nonspecific, potentially delaying the diagnosis. Approximately 15% of patients with PHPT have an underlying heritable form of PHPT that may be associated with extraparathyroidal manifestations, requiring active surveillance for these manifestations as seen in multiple endocrine neoplasia type 1 and 2A. Genetic testing for heritable forms should be offered to patients with multiglandular disease, recurrent PHPT, young onset PHPT (age ≤40 years), and those with a family history of parathyroid tumors. However, the underlying genetic cause for the majority of patients with heritable forms of PHPT remains unknown. Distinction between sporadic and heritable forms of PHPT is useful in surgical planning for parathyroidectomy and has implications for the family. The genes currently known to be associated with heritable forms of PHPT account for approximately half of sporadic parathyroid tumors. But the genetic cause in approximately half of the sporadic parathyroid tumors remains unknown. Furthermore, there is no systemic therapy for parathyroid carcinoma, a rare but potentially fatal cause of PHPT. Improved understanding of the molecular characteristics of parathyroid tumors will allow us to identify biomarkers for diagnosis and novel targets for therapy.

Bilateral ossifying fibroma affecting the jaws: Literature review, rare case report

BACKGROUND

Ossifying fibroma (OF) is a benign lesion could occur in different areas of the body and contain fibers, cells and non-organic materials in non specific amounts. It is growing could be slow or rapid and according to this an array of treatment options must be considered to avoid future complications.

CASE PRESENTATION

In this article, we present a case report of a 40-year-old female patient who visited the dentist with the intention of having a normal check up. Bilateral lesion was observed in the mandible, the patient had no medical history of trauma. The lesion was removed surgically and analyzed histologically and the result was ossifying fibroma in both sides.

DISCUSSION

Ossifying fibroma is a rare tumor to be found in the oral cavity, and the family of fibro-osseous lesions (FOLs) has in general the same pathologic features and differ from each other in clinical view so the definitive diagnosis is based on mixture of all these elements. The treatment is complete surgical excision.

CONCLUSIONS AND LITERATURE REVIEW

11 cases were discovered and archived since 1968 until now, the distribution of cases is nearly equal in the oral cavity, and the infection of females is higher than males.

Ossifying Fibroma in the Maxilla and Mandible: A Case Report With a Brief Literature Review

Fibro-osseous lesions in the jaw bones include fibrous dysplasia, ossifying fibroma (OF), cemento-ossifying fibroma, florid osseous dysplasia, and focal osseous dysplasia. OF is the most common fibro-osseous tumor that presents as a slow-growing well-encapsulated benign neoplasm composed of varying amounts of bone or cement-like tissue in a fibrous stroma well-demarcated from the adjacent normal bone. OF is most common in the jaw bones, with a predilection for the mandible. OF usually occur as solitary lesions and rarely as multiple lesions in a patient. We present clinical and radiologic features, histopathology, and surgical management of a rare case with large synchronous OFs in the mandible and maxilla and a brief review of the literature.

Alkaline Phosphatase Profile of Patients with Fibro-Osseous Lesions

INTRODUCTION

Although some studies on craniofacial fibro-osseous lesions have assayed serum alkaline phosphatase levels of affected patients, the findings of these reports are often inconclusive. The aim of this study was to determine the association between the serum ALP levels of individuals with craniofacial fibro-osseous lesions (CFOLs) and treatment outcome.

MATERIALS AND METHODS

Consecutive patients who presented at the Ahmadu Bello University Teaching Hospital, Zaria from May, 2016 to December, 2017 with lesions histologically diagnosed as CFOLs. The Speight and Carlos' (2006) classification of CFOLs was adopted, and the serum ALP level of patients and their age- and- gender matched apparently healthy controls were measured at presentation, and repeated at the 3rd and 6th post-operative months for subjects only. Treatment outcomes were assessed 6 months post treatment.

RESULTS

Fifty cases of CFOLs were recorded with a male preponderance, while fibrous dysplasia was the most prevalent lesion, and the maxilla was the most affected jaw (62%). Only 11 subjects had elevated serum ALP levels at presentation, and the mean serum ALP level of subjects with CFOLs was higher (341.2 ± 198.1 IU/L) than that of their age-and gender-matched controls (190.7 ± 110.2 IU/L). With the exception of subjects whose lesions recurred, there was a decrease in the mean serum ALP levels of subjects by the 3rd (245 ± 170.2 IU/L) and 6th (240.5 ± 172.7 IU/L) months post-treatment. Thirty three subjects had elimination of lesions, while three cases each recurred or developed morbidity.

CONCLUSION

The treatment outcomes of patients with fibrous dysplasia appear to be associated with their serum ALP level. Therefore, serial serum ALP level monitoring suggested in the management of patients with fibrous dysplasia of the craniofacial region.

Combined lesion of central giant cell granuloma and ossifying fibroma: A case report of a rare event in oral cavity

Introduction and importance

Giant cell granulomas (GCG) and ossifying fibroma (OF) of the jaw are benign reactive lesions. GCG characterized by the presence of abundant multinucleated giant cells in a cellular stroma. On the other hand, the characteristic feature of OF is benign connective tissue replaces the normal bone. Combination of these two lesions, GCG with OF, in the jaw is extremely rare.

Case presentation

A 35-year-old woman presented with complains of right jaw swelling with no history of previous disease or lesion and no family history of such lesions. By physical examination, a painful swelling in the right jaw was observed. A computed tomography scan of the facial bone showed a large, expansible, lytic lesion with narrow zone of transition and internal septations, involving the right side of the maxilla and floor of the right maxillary sinus. Histopathologic examination revealed a lesion with combined features of OF and GCG.

Clinical discussion

GCG and OF are two of the most frequent oral lesions. Presence of both tumors in one patient as a combined lesion is highly unusual, with only a few reported cases in the literature. On clinical and radiologic examination, diagnosing such a combined lesion is not possible, however, such lesions can be easily diagnosed by microscopic examination, indicating the importance of pathologic examination.

Conclusion

Occurrence of combined OF and GCG is a rare event. Proper histopathologic evaluation can contribute to accurate diagnosis and better management of such lesions. Confirmative diagnosis of such lesions by radiology alone is not possible.

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Giant cell granuloma and fibro-osseous lesions are benign neoplasms of oral cavity.

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Aggressive central giant cell granuloma has malignant potential.

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Combined lesion of giant cell granuloma with ossifying fibroma within one lesion is a rare event.

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Accurate diagnosis can be made by histopathologic evaluation, which is very important for the management of this lesion.

Benign mesenchymal odontogenic tumors of the maxillofacial bones: A report of 3 cases with 3 years follow-up

Benign mesenchymal odontogenic tumors are lesions derived from the mesenchymal components of the tooth-forming apparatus and are consequently found within the jawbone. Benign fibro-osseous tumors are part of this category of lesions in which normal bone is substituted, initially by fibrous tissue and within time become infiltrated by osteoid and cementoid elements. They are asymptomatic, slow-growing lesions and remain undiagnosed until swelling of the face becomes prominent and they share similar radiological characteristics. Herein, we report three cases of ossifying fibroma, cemento-osseous fibroma and periapical cemento-osseous dysplasia and analyze all the correlating factors, clinical history, radiological and histological features, intraoperative appearance, and treatment with a 3-year follow-up period. Despite the advances in the identification of these pathologies, clinicians still face difficulties in their classification and the diagnosis due to overlap in both histological and radiographic findings. An accurate final diagnosis is essential for appropriate treatment and an informative prognosis.

First presentation of a frameshift mutation in the SETD2 gene of a juvenile psammomatoid ossifying fibroma (JPOF) associated with an aneurysmal bone cyst

Background

The rarity of juvenile psammomatoid ossifying fibroma (JPOF) and lack of cytogenetic studies prompted us to report a novel SETD2 gene mutation in a benign odontogenic tumour.

Case presentation

A 21-year-old man presented with a hard, expanded mandibular cortex. Computed tomography revealed multilocular radiopacity in the mandible; this was reconstructed via segmental mandibulectomy using a vascularised iliac crest flap. Based on the clinical and histological findings, we diagnosed JPOF associated with an aneurysmal bone cyst. Microscopically, the solid area was characterised by many rounded or angular ossicles in a cellular fibrous stroma. The stromal cells were spindle-like or stellate. Next-generation sequencing detected a frame shift mutation of the SETD2 gene, while the copy number was normal.

Conclusions

Our findings suggest further genetic studies should be performed to assess whether this mutation is related to tumour genesis. 

Parafibromin Abnormalities in Ossifying Fibroma

Ossifying fibromas are very rare tumors that are sometimes seen as part of the hyperparathyroidism-jaw tumor syndrome (HPT-JT), which is caused by inactivating mutations of the HRPT2/CDC73 tumor suppressor gene. CDC73 mutations have been identified in a subset of sporadic cases but aberrant expression of the encoded protein, parafibromin, has not been demonstrated in ossifying fibroma. We sought to determine if loss of parafibromin regularly contributes to the development of sporadic, nonsyndromic ossifying fibroma. We examined a series of 9 ossifying fibromas, including ossifying, cemento-ossifying, and juvenile active variants, for parafibromin protein expression by immunohistochemistry and for CDC73 sequence abnormalities by Sanger sequencing and/or targeted AmpliSeq panel sequencing. Four ossifying fibromas showed a complete absence of nuclear parafibromin expression; loss of parafibromin expression was coupled with aberrant cytoplasmic parafibromin expression in 1 case. CDC73 mutations were detected in 2 cases with aberrant parafibromin expression. These results provide novel evidence, at the level of protein expression, that loss of the parathyroid CDC73/parafibromin tumor suppressor may play a role in the pathogenesis of a subset of ossifying fibromas.

Simultaneous presentation of juvenile ossifying fibroma in the maxilla and mandible: a case report

INTRODUCTION

Juvenile ossifying fibroma (JOF) is a controversial and uncommon lesion that has been distinguished from the larger group of ossifying fibromas because of distinct clinical features and some morphological peculiarities. Furthermore, JOF shows an aggressive biological behavior that has led researchers to consider it a benign neoplasm, resulting in its differential diagnosis with important benign and malignant bone neoplasms.

PRESENTATION OF CASE

This study describes a case of synchronous presentation of JOF in the mandible and maxilla of a young patient. In addition, the literature was reviewed to identify clinical-pathologic features and possible factors that could help establish the correct diagnosis. A 26-year-old male patient presented simultaneously a lesion affecting the body, angle and ramus of the left mandible and another lesion in the left maxilla. Both lesions were well delimited and radiolucent, being unilocular in the maxilla and multilocular in the mandible. The mandibular lesion was partially resected and the maxillary lesion was submitted to curettage. The diagnosis was JOF.

DICUSSION

A delay in seeking medical care and a late diagnosis can have serious consequences for the postoperative functional and esthetic outcome. Much care should be taken during establishment of this diagnosis since an equivocal diagnosis can have serious consequences for the patient in terms of treatment.

CONCLUSION

After 1 year, the patient shows no signs or symptoms of recurrence of the lesions and was referred for reconstructive surgery of the mandible. An early and correct diagnosis is necessary to permit the best therapeutic management.

Gnathic Bones and Hyperparathyroidism: A Review on the Metabolic Bony Changes Affecting the Mandible and Maxilla in case of Hyperparathyroidism

Parathyroid glands secrete the parathyroid hormone that plays an essential role in bone remodeling. Excessive production of parathyroid hormone causes a common metabolic bone disorder known as hyperparathyroidism that is classified into primary, secondary, or tertiary. In hyperparathyroidism, the late bony complication is manifested as a giant cell osteolytic lesion called "brown tumor." Primary hyperparathyroidism is usually a sporadic disorder, but in minority of cases it occurs in inherited forms, and one of these forms is the hyperparathyroidism-jaw tumor syndrome, which is characterized by primary hyperparathyroidism and ossifying fibroma in the mandible and/or maxilla.

CDC73 gene mutations in sporadic ossifying fibroma of the jaws

Background

The tumor suppressor gene CDC73 was found to be associated with hyperparathyroidism-jaw tumor syndrome (HPT-JT), which is characterized by parathyroid adenoma or carcinoma, ossifying fibroma (OF) of the jaws, and renal and uterine lesions. Mutations in CDC73 have also been frequently detected in sporadic parathyroid carcinomas and renal tumors. However, the prevalence and range of CDC73 mutations in sporadic OFs have not been established.

Methods

We directly sequenced coding and flanking splice junctional regions of CDC73 in 40 cases of sporadic OF of the jaws. We also used immunohistochemistry to detect parafibromin, the protein product of CDC73, in those cases.

Results

Two novel CDC73 mutations were identified in 2 of the 40 cases (5 %). Both were somatic mutations located in exon 1 of the coding region. Strong parafibromin expression was detected in all 40 cases, irrespective of the presence of CDC73 mutations.

Conclusions

Mutations inCDC73 were rare in sporadic OF of the jaws, but may affect the pathogenesis of a small subset of tumors of this type.