Fig. 8.

53-year-old woman with metastatic insular carcinoma of thyroid gland.

A. Mediolateral oblique mammogram shows focal asymmetry in left upper outer breast (arrows). B. US of left upper outer breast shows circumscribed benign-looking mass with multifocal cystic changes, mimicking resolving hematoma in middle of breast parenchyma. C. Contrast enhanced neck CT scan reveals large heterogeneous low density mass in left thyroid gland (arrow). D. Follow-up US after 4 months shows markedly enlarged hypoechoic mass with circumscribed margins and multiple small internal cystic portions (arrows). US = ultrasound