Shear wave elasticity of breast lesions: would it be correlated with the extracellular matrix components?

Malignant breast lesions have higher shear wave elasticity than benign lesions, and the occurrence of breast lesions is accompanied by changes in extracellular matrix (ECM) components which are related to invasion and metastasis of breast lesions. Therefore, the purpose of this study was to analyze the relationship between shear wave elasticity and ECM components in breast lesions.

From March 2012 to March 2013, 69 consecutive breast lesions in 65 patients were eventually included in this study. The shear wave elasticity features of the lesions and their diagnostic performance were analyzed. ECM components of the specimens were analyzed by Van Gieson (VG) dye, Aldehyde Fuchsin dye and immunohistochemical staining, respectively. Image-Pro Plus 5.1 software was used for quantitative analysis of the areas of the components of ECM.

The elasticity ratio of lesions to peripheral parenchyma, maximum elasticity and mean elasticity of malignant lesions were significantly higher than those of benign lesions (3.5±0.7 vs. 2.3±0.9, 112.5±27.2 vs. 45.0±20.5, 44.0±10.3 vs. 26.0±14.0 kPa, respectively; P=0.014, P=0.000, P=0.000, respectively). The contents of collagen fiber and elastic fiber of benign lesions were significantly lower than those of malignant lesions (9,717.2±2,548.1 vs. 13,757.2±2,926.6, 9,257.5±2,392.8 vs. 14,384.4±2,853.7, P<0.001, P<0.001). Multiple linear regression analysis showed that collagen fiber and elastic fiber were independent variables correlated to the maximum elasticity of breast lesions (r² =0.564, P=0.014).

The contents of collagen fiber and elastic fiber are positively correlated with the elasticity of breast lesions, which suggested that further study of the mechanism of ECM might provide a new method for the study of the elasticity of breast carcinoma.