Case report: Aneurysmal bone cyst arising from the anterior ethmoid sinus

Abstract

Introduction: Aneurysmal bone cyst (ABC) is an expansible bone lesion that occurs usually in long bones. Rarely, it involves the head and neck regions. Case report: A 31-year-old woman who presented with epistaxis and right side nasal cavity mass. Radiologically, there was an expansible lytic anterior ethmoid lesion, which extended to right maxillary, frontal sinuses, and nasal cavity causing nasal septum deviation to the left side. Several biopsies were taken during functional endoscopic sinus surgery (FESS) and showed fibrous proliferation with new bone formation, giant cells, and hemorrhagic cysts, which are the characteristics of the aneurysmal bone cyst. Then, the patient underwent surgical excision of the mass. Conclusion: ABC is a rare disease in the head and neck and can be confused with other diagnoses on imaging. Therefore, the histopathological diagnosis is required. Regular follow up after the surgical excision using imaging is necessary considering previously reported recurrence rate. Keywords: Aneurysmal bone cyst, Ethmoid sinus, Blood-filled lesion