[The application of 3-dimensional shear wave elastography in the therapeutic effect evaluation of neoadjuvant chemotherapy for Her-2 positive breast cancer patients].

Objective: To investigate the clinic value of ultrasound 3-dimensional shear wave elastography (3D-SWE) in therapeutic effect evaluation of neoadjuvant chemotherapy (NAC) for HER-2 positive breast cancer patients. Methods: A total of 43 lesions from 43 HER-2 positive breast cancer patients were selected and all of the lesions were confirmed by biopsy. Ultrasound examination was performed routinely before each chemotherapy cycle. The interested regions were selected under the 3-dimensional (3D) elasticity and gray-scale mode, the relevant data such as shear waves in the transverse, longitudinal and coronal sections of the mass were generated automatically. According to the histopathological results, the patients were divided into the pathological complete remission (pCR) group and the incomplete remission (non-pCR) group. The maximum elastic hardness value (Emax) and the reduction degree (ΔEmax) of the lesions in the two groups were measured and compared in each cycle of NAC. The accuracy of 3D-SWE technique for predicting the efficacy of NAC was evaluated using indicators such as sensitivity, specificity and area under the receiver operating characteristic (ROC) curve. Results: The clinicopathologic features between pCR group (18 cases) and non-pCR Group (25 cases) were not significantly different (P>0.05). Compared with pre-chemotherapy, the Emax values of pCR group and non-pCR Group during chemotherapy were declined (P<0.05). Moreover, the Emax values of pCR group before and after chemotherapy were lower than those of non-pCR group (P<0.05). At the end of the first cycle of chemotherapy, the predictive specificity, sensitivity and area under the curve (AUC) of pCR group were 72.0%, 83.3% and 0.838 (95%CI=0.680~0.930) respectively when the cutoff value of Emax was 118 kPa. At the end of the second cycle, the predictive specificity, sensitivity and AUC of pCR group were 76.0%, 83.3% and 0.863 (95%CI=0.720~0.940) respectively when the cutoff value of Emax was 87 kPa. At the end of the third cycle, the predictive specificity and sensitivity and the AUC of the pCR group were 88.0%, 77.8% and 0.893 (95%CI=0.760~0.970) when the cutoff value of Emax was 57 kPa. At the end of the fourth cycle of chemotherapy, the predictive specificity, sensitivity and AUC of pCR group were 92.5%, 88.9% and 0.960 (95%CI=0.850~0.990) respectively when the cutoff value of Emax was 30 kPa. After one cycle of NAC, the predictive sensitivity and specificity and AUC of pCR group were 88.0%, 60.0%, and 0.719 (95%CI=0.620~0.890) when the cutoff value of ΔEmax was 16.8%. After two cycles, the predictive sensitivity, specificity and AUC of pCR group were 55.5%, 80.0% and 0.712 (95%CI=0.550~0.840) when the cutoff value of ΔEmax was 34.9%. After three cycles, the predictive sensitivity, specificity and AUC of pCR group were 67.4%, 81.2% and 0.779 (95%CI=0.680~0.930) when the cutoff value of ΔEmax was 55.2%. After four cycles, the predictive sensitivity, specificity and AUC of pCR group was 72.3%, 92.0% and 0.831 (95%CI=0.690~0.930) when the cutoff value of ΔEmax was 75.1%. Conclusion: The Emax and ΔEmax values measured by 3D-SWE technology can predict the curative effect of NAC for breast cancer.