Cholesterol granuloma of the breast mimicking carcinoma: report of a case.

Cholesterol granuloma of the breast is a rare benign condition which is often clinically and radiologically indistinguishable from breast carcinoma. We herein report the case of a 62-year-old asymptomatic woman who was found on a routine breast examination to have an elastic hard mass, measuring 0.9 cm in diameter, in the upper outer quadrant of the left breast. Physical examination and ultrasonography strongly suggested a carcinomatous lesion. A cytological examination of a fine-needle aspiration biopsy specimen was inconclusive because of the paucity of epithelial cells. A histological examination of excisional biopsy materials showed scattered cholesterol crystals arranged in irregular, parallel arrays, surrounded by histiocytes and giant cells, which were consistent with a diagnosis of cholesterol granuloma. This case report indicates the importance of performing a histological examination to establish the final diagnosis of cholesterol granuloma. We believe that a better awareness of this breast disease might help to prevent both a misdiagnosis and unnecessary surgery.