Non-ossifying fibroma (metaphyseal fibrous defect) of the mandible

Literature Review, Case Presentation and Management of Non-ossifying Fibroma of Right Angle of Mandible: More Than just a Cortical Defect!

Non-ossifying fibroma (NOF) of jaw bones are rare. While NOF is the most common benign bone tumor of long bones with pathognomonic radiological features and bear a tendency for self-regression, gnathic NOF appears to be comparatively larger in size and behave more aggressively. A 16 years old female patient reported with painless swelling of the right side of the face of 4 months duration. Radiographic analysis showed a unilocular radiolucent lesion of right angle of the mandible with ill-defined margins, cortical perforation and thinning of inferior border. The lesion was provisionally diagnosed as odontogenic keratocyst/unicystic ameloblastoma and incisional biopsy was performed. The histopathological features and immunohistochemical characteristics favored a diagnosis of NOF. The lesion was excised and reconstructed. The excised specimen confirmed the diagnosis. There are no signs of recurrence at 18 months follow-up. NOF should be considered in the differential diagnosis of uni-/multilocular radiolucencies of jaws particularly the posterior mandible.

Non-ossifying fibroma of the mandible in a 4-year-old child: A rare case and review of the literature

Non-ossifying fibromas usually occur in the metaphysis of the long bones in children, and are extremely rare in the mandible. Here, we present a case of non-ossifying fibromas which occurred in the mandible of a 4-year-old boy. The patient had no complaint of ache. Laboratory blood examination of serum calcium, phosphorus, and parathormone levels was normal. Computed tomography of the maxillofacial region showed a well-defined osteolytic lesion affecting the right mandible. Microscopically, the lesion showed whorled bundles of spindle-shaped fibroblasts, as well as foam cells, mingled with scant multinucleated giant cells, without any bone formation. It is necessary to distinguish non-ossifying fibromas from other giant cell-containing lesions because of the extremely infrequent occurrence of this lesion in the mandible. We reviewed the histologic features of 14 cases of non-ossifying fibromas involved in the jaw.

Benign fibrohistiocytic jaw lesions: a 48-year clinicopathologic analysis and review of the literature

OBJECTIVE

Intra-osseous fibrohistiocytic lesions have long been reported in the literature; evidence suggests they represent a heterogeneous group of reactive and neoplastic processes. This study evaluated a series of gnathic fibrohistiocytic lesions to identify and categorize their clinical, radiographic and morphologic spectrum.

STUDY DESIGN

A retrospective case search over 48 years was conducted for maxillary and mandibular intra-bony fibrohistiocytic lesions. Diagnoses were confirmed and demographic, radiographic, clinical and follow-up data was analyzed.

RESULTS

Fifty cases met the inclusion criteria. Most cases (80%) were found in the second through fourth decades (mean, 29 years). The most common location (86%) was the posterior mandible. Radiographic presentations varied, but a few patterns emerged, including a distinctive mottled, honeycomb type with punctate lucencies. All cases demonstrated fibrous components admixed with variable histiocytes. Eight cases (16%) were histiocyte-rich with dominant sheets of xanthoma cells. Immunohistochemical staining revealed strong CD68 and CD163 expression, along with variable smooth muscle actin staining. The vast majority (92%) of cases were treated conservatively. Available follow-up showed lesional stability in 17 cases (average, 85 months) with 2 recurrences (24 months each) and no evidence of malignant transformation.

CONCLUSIONS

This study is the largest to date of fibrohistiocytic gnathic lesions, revealing distinctive radiographic and histologic findings and characteristic clinical and immunophenotypic features. Available evidence suggests that most of these are indolent, slow-growing lesions amenable to conservative therapy.

Non-ossifying Fibroma of Mandible in a Four-Year-Old Girl: A Case Report

Non-ossifying fibroma (NOF) is not prevelant in the mandible. It appears mostly in the long tubular bones in children and adolescents. We are presenting a case of a four-year-old girl reported to the maxillofacial department with painless swelling over the lower right side of the jaw. On the orthopantomogram (OPG), a well-defined multilocular radiolucency with a sclerotic margin was present. On computed tomography (CT), an expansile lytic lesion with cortical thinning without a breach in cortical continuity was noted. By correlating clinical and radiological features, a diagnosis of odontogenic and/or osteogenic lesion was made. The patient was considered for an excisional biopsy with curettage. On histopathology, NOF was confirmed. On postoperative follow-up, there was no sign of recurrence, and bone regeneration was significant.

Primary Intraosseous Xanthomas of the Jaws: A Series of Six Cases Including an Example with Formation of Apoptosis-Related Hyaline Globules, So-Called "Thanatosomes"

Primary intraosseous xanthomas of the jaws (PIXJ) are rare and predominantly affect the posterior mandible (86%) of normolipemic patients, with a mean age of 30 years and no gender predilection. Clinically, PIXJ exhibit indolent biologic behavior; curettage is considered treatment of choice. Only 36 PIXJ have been reported. Apoptosis-related hyaline globules (HGs), also known as "thanatosomes", have not been previously reported in PIXJ. Cases diagnosed as xanthoma of bone were retrieved. Six cases fulfilling currently accepted criteria were identified and their clinicopathologic and immunohistochemical properties are presented herein. Mean age for PIXJ was 21.8 years (range = 12-33) and F:M ratio = 2:1. All cases presented as well-demarcated, unilocular or multilocular radiolucencies. Microscopically, PIXJ featured sheets of lipid-laden macrophages with eosinophilic or foamy cytoplasm. A secondary fibroblastic population lacking storiform pattern was evident in two cases. Adipocytes (3/6), peripheral neurovascular bundles (1/6), bone fragments (3/6) and dystrophic calcifications (3/6) were observed enclosed by the xanthoma cells. Notably, one case exhibited numerous, spherical, eosinophilic HGs containing apoptotic nuclei. PIXJ were consistently CD68(+) and negative for CD1α and S100. CD45 decorated lymphocytes and the membrane of foamy histiocytes. Xanthoma cells stained for lysozyme and plasma proteins including alpha-1 antitrypsin (AAT), IgG and IgA in one probed case. HGs were lysozyme(+), AAT(+), IgG(+), IgA(+), PAS(+) and diastase-resistant, and fuchsinophilic with Masson's trichrome. PIXJ represent infrequent, solitary, mandibular lesions with a predilection for the second and third decade of life. Thanatosomes associated with cell injury and death can be present in PIXJ.

The non-ossifying fibroma: a case report and review of the literature

The non-ossifying fibroma (NOF) is a benign, non-neoplastic lesion most commonly seen in the metaphyses of the long bones in children. While rare, the NOF has been reported in the mandible. The NOF in the extra-gnathic skeleton has a characteristic radiographic appearance, is typically asymptomatic and has a variable histologic make-up. Correlation of the radiographic appearance, clinical presentation and histopathology allows for differentiation of the NOF from odontogenic and non-odontogenic cysts and tumors. We report a new case of this interesting entity and review the radiographic, clinical and histologic features of the gnathic NOF reported in the literature. A thorough search of the English language literature returned a total of 19 cases of NOF involving the gnathic bones.