Spindle cell lipoma of the breast: a case report and literature review.

Fine-needle aspiration cytology (FNA) was performed on a breast lump in a 66-year-old female, clinically thought to be a carcinoma. The cytological findings were reported as suspicious of malignancy. Subsequent histological examination showed a tumour macroscopically and microscopically identical with six other cases previously described as benign spindle cell tumours of the breast. This report highlights yet another diagnostic pitfall in FNA cytology of the breast. The presence of floret cells in this case has not been previously reported but supports the concept that this lesion is the same as a spindle cell lipoma, from which it is virtually indistinguishable on light microscopy. The lesion affects both male and female breast, is predominantly single but may be multiple, and follows a benign course. Local excision is curative.