49-year-old woman presents for follow-up right breast ultrasound for an indeterminate sonographic lesion which was diagnosed at outside hospital ultrasound. In the right breast 10:00 position, 10 cm from nipple, there is a round anechoic lesion measuring 4 x 4 mm with associated thin peripheral hyperechogenicity compatible with calcification with is most consistent with an oil cyst. This correlates with the lesion seen on ultrasound outside hospital dated 1/26/2016. On review of the outside mammogram dated 2/6/2016, several oil cysts are also seen in the right breast.
Right breast finding is probably benign, likely an oil cyst. Recommend a 6 month ultrasound follow up to evaluate stability. Note that the patient subsequently had two stereotactic biopsies after this ultrasound for other areas in the right breast. BIRADS: 3 - Probably benign finding.RECOMMENDATION: T - Take Appropriate Action - No Letter.