Ossifying Fibromas of the Head and Neck Region: A Clinicopathological Study of 45 Cases

Small biopsies in the head and neck: Bone and soft tissue

Bone and soft tissue lesions in the head and neck encompass not only a broad morphologic spectrum but also significant inherent clinicopathologic overlap. Epidemiology, radiology, and location - similar to the diagnostic assessment in other sites - are especially important considerations in the context of an established mesenchymal proliferation. Herein, the approach towards diagnosis is stratified by morphology (spindle, sarcomatoid, epithelioid, round cell), cellular lineage (fibroblastic, nerve sheath, rhabdomyogenic), and tumor grade (benign, low- to high-grade malignant) as the basis of further immunohistochemical or molecular investigation.

Psammomatoid ossifying fibroma in the extraconal space: a case report

A 24-year-old patient with left eye proptosis and intermittent pain for 5 months was admitted to our hospital. Physical examination revealed neither extra ocular muscle limitations nor visual field defects. Magnetic resonance imaging (MRI) revealed a multicystic mass in the left extraconal space compressing the superior oblique muscle and adjacent frontal lobe. Layered hemorrhage was observed within the lesion in the 1-month follow-up MRI. Dynamic contrast enhanced imaging showed mild increased perfusion of the surrounding peripheral portion. Magnetic resonance spectroscopy showed an increased lactate/lipid peak of 1.3 ppm. Combined open and endonasal surgery was performed, and the final diagnosis was psammomatoid ossifying fibroma. The tumor was positive for vimentin, and negative for smooth muscle actin, S100 and epithelial membrane antigen. Despite its rarity, psammomatoid ossifying fibroma should be considered when multicystic lesions with peripheral enhancement near the orbit exhibit progressive inner hemorrhage.