Fig. 3
From: Multifocal cholesterol granulomas of the anterior mediastinum
a Microscopically, the nodule was identified as a cholesterol granuloma with cholesterol clefts arranged in an alveolar-like growth pattern. Fibrosis was observed in part of the lesion (small arrow). b Areas containing inflammatory infiltrates and multinucleated giant cells were observed in the granuloma. c The cholesterol clefts (large arrow) were surrounded by inflammatory infiltrates, histocytes, and multinucleated giant cells, some of which had phagocytosed hemosiderin granules (small arrow). In addition, osseous metaplasia (arrowhead) was observed close to the cholesterol clefts. d The cholesterol granuloma was adjacent to the remnants of the thymic tissue with the presence of Hassall’s corpuscles (large arrow)