Adult-Onset Orbital Xanthogranuloma Presenting As A Chronic Painless Upper Eyelid Mass

Background: Adult-onset xanthogranuloma (AOX) is a rare, non-Langerhans histiocytic disorder of the orbit, typically presenting without systemic involvement. Methods: We report the case of a 48-year-old male with a 7-year history of progressive, painless right upper eyelid swelling. Results: Imaging revealed a well-circumscribed, enhancing intraconal mass, and histopathological examination following orbitotomy confirmed xanthogranulomatous inflammation. Stains for infectious organisms were negative, and no systemic abnormalities were identified, supporting a diagnosis of isolated AOX. Although the patient experienced transient improvement with corticosteroids, definitive management required surgical excision. Conclusion: This case highlights the importance of considering AOX in the differential diagnosis of chronic orbital masses and underscores the role of histopathology in establishing a definitive diagnosis.