[Changes in MR imaging appearance of breast cancer after intra-arterial infusion chemotherapy]

The purpose of this study was to evaluate whether the characteristic change in breast cancer related to chemotherapeutic response (CR) and the effect of invasion and toxicity in the skin and pectoralis muscle exist on MR imaging after intra-arterial infusion chemotherapy. A total of 11 patients with histologically proven breast cancer underwent MR study before and after chemotherapy. Changes in images and the dynamic curve-after-chemotherapy were evaluated, including time to maximum signal intensity (SI) and the early phase enhance ratio (EPER) in the tumor. In the tumor, changes in the dynamic curve, time to maximum SI, EPER and necrosis did not correlate with CR, but change in SI on T2-weighted images was suggested to do so. Changes in the dynamic curve and images in the pectoralis muscle and in images on the skin were suggested to correlate with CR. In addition, images changed for the worse in many cases of invasion and toxicity in the pectoralis muscle and in some cases of invasion in the skin. In conclusion, tumors had fewer imaging changes correlating with CR after intra-arterial infusion chemotherapy. Changes for the worse in images of the pectoralis muscle and skin may be useful for the evaluation of invasion.