Shear-wave Elastography Of Breast Invasive Ductal Carcinoma: Correlation Between Quantitative Elasticity Value And Protein Expression

Objective: To investigate the relationship between shear-wave elastography(SWE)parameters and protein expression and molecular subtype in breast invasive ductal carcinoma(IDC).Methods: A prospective study was conducted on female patients who came to our hospital for surgery or puncture biopsy due to a solid breast mass from March 2017 to July 2018.We selected the shear wave elastography ultrasonic diagnostic instrument of France sonics company.Routine ultrasound examination was performed at first to record the size and location of the Breast masses and classify them according to the Breast imaging reporting and data system(BI-RADS).Then SWE was performed on the masses.Two elastographic images from two orthogonal planes were obtained for each lesion,and then SWE elastic quantitative parameters,including the maximum stiffness(Emax),mean stiffness(Emean),ratio of stiffness of the mass to stiffness of the surrounding fatty tissue(Eratio),are measured with ROI = 2 mm.Record the pathologic results and protein molecules(estrogen receptor(ER),progesterone receptor(PR),human epidermal factor receptor-2(HER2),Ki67,p53)expression.Based on the protein molecules expression,the tumors were divided into four subtypes: Luminal A,Luminal B,HER2-enriched and Basal-like.SPSS 22.0 software was used for analysis.We used Student’t-test or one-way ANOVA and multiple linear regression to evaluate the relationship between elastic quantitative parameters and protein molecular expression and molecular subtypes.P <0.05 was considered statistically significant.Results: A total of 225 IDC patients(229 masses)were included in the study.At univariate analysis,lesion size,histologic grade and Ki67 expression were significantly associated with three quantitative elasticity(all P < 0.05).PR status,p53 exepression and molecular subtypes was significantly associated with square root of maximum elasticity(P=0.011,P=0.016,P=0.022).The difference of the mean square root of mass elasticity in different PR states was statistically significant(P=0.004).The difference of logarithm of elasticity ratio between different p53 expression masses was statistically significant(P=0.011).However,there was no significant correlation between age,tumor location,lymph node status,ER status,HER2 expression and the three quantitative values(all P > 0.05).At multivariate analysis,only lesion size was independent statistically associated with quantitative elasticity values,and none of the remaining factors was independent.Conclusion: The larger the tumor,the higher the histologic grade,the higher the Ki67 expression,the PR negative and the p53 positive were positively correlated with the higher elastic values.However,only the size of the mass had an independent correlation with the elastic value in the multivariate analysis.We were unable to demonstrate a correlation between protein molecule expression and molecular subtypes and tumor hardness.