Focal cholesterol granuloma in the anterior mediastinum: [18F]-fluoro-2-deoxy-D-glucose-positron emission tomography and magnetic resonance imaging findings.

Cholesterol granuloma is a foreign-body type granuloma that forms in reaction to cholesterol crystals. We report a rare case of focal cholesterol granuloma in the anterior mediastinum of a 62-year-old asymptomatic man that presented as an indeterminate anterior mediastinal nodule on [18F]-fluoro-2-deoxy-D-glucose-positron emission tomography and computed tomography scans. T1- and T2-weighted magnetic resonance images revealed markedly hypo-intense signals reflecting pathologic hyalinized collagen fibers. Magnetic resonance signal characteristics might be helpful for distinguishing benign cholesterol granulomas from malignant neoplasms.