Comparison of proliferative potential in variants of ossifying fibroma (OF) of craniofacial complex

Comparison of proliferative potential in JTrOF , PsOF and OF of craniofacial complex using CDK4 and pHH3. Fibro-osseous lesions (FOL) refers to a poorly defined diverse group of lesions affecting the jaws and craniofacial complex. This spectrum of lesions includes fibrous dysplasia, cement-osseous dysplasia and two histological variants of ossifying fibroma - Despite benign neoplasms, both the variants of ossifying fibroma are characterized by rapid growth, potential for local invasiveness and a tendency to recur. According to the literature, the recurrence rate of JTrOF is about 20% where as PsOF is from 30-56%. Diagnosis is based on histopathology and imaging of the lesion. Early diagnosis allows for the resection of a smaller lesion , reducing the chance of damage to nearby structures. Various biomarkers such as oncogenes CDK4, MDM2, p53 and α-SMA have been investigated in bone pathology to predict biological behaviour of these lesions for precise treatment planning. Immunohistochemical expression of CDK4 and pHH3 will be assessed in histopathological diagnosed cases of juvenile trabecular ossifying fibroma, psammamatoid ossifying fibroma and conventional ossifying fibroma. The immunohistochemical expression of CDK4 was 100% in JTrOF and PsOF and 60% in OF. The expression of pHH3 was weak and focal in JTrOF and PsOF and also weak in OF. This study reveals the genetic mechanism involved in pathogenesis of aggressive variant of OF. Pre-treatment biopsy and CT scan are necessary for proper diagnosis and treatment planning of the lesion.