Cholesterol Granuloma: An Unusual and Benign Cause of Focal FDG Uptake in the Breast Detected on PET/CT.

Cholesterol granulomas are benign lesions, rarely seen in the breast, which are indistinguishable from malignancy on anatomical imaging. The FDG PET/CT of a patient referred for melanoma staging revealed a mildly FDG-avid, soft tissue nodule in the left breast. This finding was felt unlikely to represent metastatic melanoma due to the relatively low level of uptake. The lesion was not seen on follow-up mammography. Ultrasound-guided biopsy was performed, which identified this lesion as a cholesterol granuloma. This case illustrate that cholesterol granuloma can be misinterpreted as a malignant lesion on both anatomical imaging and FDG PET/CT.