Figure 1: A 35-year-old patient with invasive ductal cancer in the left breast. From (a) to (c), the maximum intensity projection (MIP) images of pretreatment, F/U-1, and F/U-2 MRI are shown. Despite the large tumor, the boundary is clearly visible and this is a mass lesion. The diagnosed tumor size before treatment is 8.4 cm. This cancer is considered as inoperable and is recommended to receive NAC. After 2 cycles of treatment the tumor has shrunk to 1.2 cm, and the size is further decreased to 0.6 cm after completing NAC. Without NAC this patient will need mastectomy and will have a high risk of positive margin. NAC allows this patient to receive breast-conserving surgery, with a good cosmetic outcome.