Cholesterol granuloma of the anterior mediastinum: A case report and literature review

INTRODUCTION: Cholesterol granulomas, which frequently present in the temporal bone of the skull, are recognized as benign lesions occurring due to chronic inflammation or hemorrhage. However, cholesterol granuloma of the mediastinum is extremely rare. PRESENTATION OF CASE: An asymptomatic 43-year-old man with an incidental finding of anterior mediastinal mass by positron emission tomography scan was referred to our hospital. Preoperative computed tomography showed a well-circumscribed nodule 2 cm in size in the anterior mediastinum. A total tumor resection through a suprasternal approach was performed. Microscopically, numerous cholesterol clefts with an alveolar-like growth pattern and foreign body reaction were observed, indicating a pathological diagnosis of cholesterol granuloma. DISCUSSION: Cholesterol granuloma is generally thought to be initiated by cell degeneration and hemorrhage resulting from trauma or inflammation. The patient's long-term rugby experience may have played a role in the development of cholesterol granuloma. It is difficult to diagnose a cholesterol granuloma based on preoperative imaging alone, and anatomy often makes preoperative biopsy or cytology difficult. CONCLUSION: Complete resection and pathological examination may be unavoidable for diagnosis and treatment.