Fig. 4

31-year-old patient presented with grade 2 IDC ER positive, PR negative, Her2 positive planned to receive AC (adriamycin and cyclophosphamide) 4 cycles and 12 cycles of taxol and herceptin. a–d SWE baseline, post-first, second, and fourth cycles, respectively. The stiffness ratio in the lesion, their change, and percent change were at first cycle 5.7, − 3.7, and − 39%. Post-second cycle, the stiffness ratio, the change in stiffness ratio, and percent change were − 7.5, 1.9, − 20%, and post-fourth cycle, the stiffness ratio, the change in stiffness ratio, and percent change were 2.5, − 6.9, − 73%. Postoperative pathology revealed npCR (RCBII)