Fig. 1

Ultrasonographic examination from the first consultation to the primary operation. a An ultrasonography (US) scan of the breast demonstrated a low-density area measuring 4.9 × 5.1 × 4.2 mm (orange arrowhead). b An US scan of the breast demonstrated a low-density area measuring 26.1 × 22.6 × 26.8 mm (orange arrowhead). c Histopathological findings of the tumor at the primary operation. Although mitotic figures were present slightly, there was no proliferative lesion or ductal invasion. The tumor was consisted of both epithelial cells, which was positive for CAM 5.2, and myoepithelial cells, which was strongly positive for α-smooth muscle actin (SMA). Ki-67 labeling index (Ki-67) and P53 were weakly positive. × 200