First reported case of mastoid process osteoma in Syria: Diagnostic and surgical management of a rare temporal bone tumor: A case report

Mastoid osteomas are rare benign osseous tumors, representing only 0.1–1% of skull osteomas. Most occur in the external auditory canal. A 32-year-old female presented with a 4-year history of a painless, firm right postauricular mass. Clinical examination revealed a fixed, non-tender lump with normal overlying skin and intact hearing. Temporal bone CT demonstrated a well-circumscribed, hyperdense exophytic lesion originating from the right mastoid cortex, without inner ear involvement. A 3D-CT reconstruction precisely delineated the lesion’s morphology. The patient underwent complete excision via retroauricular approach, with cortical drilling to ensure a margin-free resection. Histopathology confirmed compact osteoma, and no recurrence was observed at 6-month follow-up. This case underscores mastoid osteoma as a diagnostic consideration for slow-growing mastoid masses, despite its rarity. High-resolution temporal bone CT remains pivotal for diagnosis and surgical planning, while complete surgical excision ensures an excellent prognosis. • Mastoid osteomas are rare benign bony growths, representing only 0.1–1% of skull osteomas. • Diagnosis relies on clinical evaluation and temporal bone CT imaging. • Surgical excision is recommended for symptomatic cases.