FIBROUS DYSPLASIA AND ANEURYSMAL BONE CYST OF THE ZYGOMATIC BONE

Abstract

Fibrous dysplasia and aneurysmal bone cyst are benign intraosseous lesions, and the association of these lesions is rare. An 11-year-old boy presented with painless and slowly progressive enlargement of the zygomatic bone on the right side for the past 4 years. The patient did not have any systemic, metabolic, or endocrine disease. Computed tomographic revealed a lesion with a central area of bone density, ground-glass appearance, and, peripherally, insufflate aspect with internal septations determining expansion. The incisional biopsy was suggestive of a fibro-osseous lesion. Resection was performed followed by immediate reconstruction with autogenous bone graft. Microscopic examination revealed irregular shaped trabeculae of immature woven bone in a fibroblastic cell-rich stroma. Peripherally, blood-filled sinusoidal spaces lined by fibrous septa containing scattered multinucleated giant cells were present. The findings were compatible with fibrous dysplasia and aneurysmal bone cyst. The patient is disease-free after 10-month follow-up. Fibrous dysplasia and aneurysmal bone cyst are benign intraosseous lesions, and the association of these lesions is rare. An 11-year-old boy presented with painless and slowly progressive enlargement of the zygomatic bone on the right side for the past 4 years. The patient did not have any systemic, metabolic, or endocrine disease. Computed tomographic revealed a lesion with a central area of bone density, ground-glass appearance, and, peripherally, insufflate aspect with internal septations determining expansion. The incisional biopsy was suggestive of a fibro-osseous lesion. Resection was performed followed by immediate reconstruction with autogenous bone graft. Microscopic examination revealed irregular shaped trabeculae of immature woven bone in a fibroblastic cell-rich stroma. Peripherally, blood-filled sinusoidal spaces lined by fibrous septa containing scattered multinucleated giant cells were present. The findings were compatible with fibrous dysplasia and aneurysmal bone cyst. The patient is disease-free after 10-month follow-up.