Shear Wave Elastography Combined with Molecular Subtype in Early Predicting Response to Neoadjuvant Chemotherapy for Breast Cancer: A Prospective Case-control Study

Abstract

\n Background: This study was designed to investigate the performance of quantitative shear wave elastography (SWE) and the accuracy of SWE with the molecular subtype for early prediction of pathological response of breast cancer to neoadjuvant chemotherapy (NAC).Methods: In this prospective case-control study, 102 patients were screened from September 2016 to August 2020. Characteristics of conventional ultrasonography (US), SWE and contrast-enhanced magnetic resonance imaging (CE-MRI), were recorded, and the changes were compared to the pre-NAC baseline data. The pathological response was classified according to the Miller Payne grading system. Multivariate logistic regression was used to develop a predictive model for the response to NAC. Results: Significant differences related to changes in SWE characteristics of breast lesions between between pathological response groups were observed earlier than size on the conventional US and MRI images. According to the multivariate predictive model, the best parameter for predicting the pathological response after the first cycle of NAC was the molecular subtype of the tumor [area under the curve (AUC) = 0.83] with low sensitivity (66.04%). Better predictive performance was achieved when △AE/B and the molecular subtype were applied in combination after the second cycle of NAC (AUC = 0.92) with a higher sensitivity (86.79%). The predictive performance of molecular subtype combined with △AE/B and △SWVmean after the third and fourth cycles of NAC were improved (AUC = 0.94).Conclusion: The SWE can be an early predictor of the pathological response to NAC for breast cancer. The combination of SWE and the molecular subtype may be a preferred method for the clinical evaluation of NAC to facilitate the personalization of treatment regimens for breast cancer.