Figure 6: A 48-year-old patient with a mass lesion (invasive ductal cancer) in the right breast and an enlarged lymph node in the axilla. From (a) to (c), the maximum intensity projection (MIP) images of pretreatment, F/U-1, and F/U-2 MRI are shown. The size of the primary tumor in the breast is 2.8 cm before treatment, which shrinks down to 1.1 cm in F/U-1 and reaches a complete response in F/U-2 after completing NAC. The node is also responding well and shows size shrinkage from 4.8 cm before treatment to 3.3 cm in F/U-1 and to 2.1 cm in F/U-2. In addition to evaluating the response of primary tumor, MRI can also be used to evaluate the response in the nodes. This patient is confirmed to reach pCR in the post-NAC pathological examination, with one positive node.