Correlation of the strain elastography-derived elasticity scores with prognostic histologic features, immunohistochemical markers, and molecular subtypes of invasive ductal carcinoma

Purpose To investigate the correlation of the strain elasticity of breast cancer with histologicfeatures, immunohistochemical markers and molecular subtypes that are known to be factorsrelated to prognosis.Materials and Methods B-mode ultrasound and strain elastography were performed in 123 patients(mean age, 53.4; range, 28-82) with invasive ductal carcinoma (IDC) (mean size, 1.54 cm;range, 0.4-7.0 cm). Histologic grade, lymph node (LN) status, lymphovascular invasion, immu-nohistochemical biomarkers [estrogen receptor, progesterone receptor, human epidermal growthfactor receptor 2 (HER2), CK5/6, epidermal growth factor receptor, and Ki-67] and molecular subtypeswere determined from surgical pathology reports. The relationships between these factors and elasticityscores were evaluated.Results LN involvement was associated with a higher elasticity score which was statistically significant(p = 0.042). The tumor size, lymphovascular invasion, histologic grades, immunohistochemicalmarkers and molecular subtypes had no significant correlation with the elasticity score (p > 0.05 forall). However, the IDCs with larger size and a positive lymphovascular invasion tended to have higherelasticity scores. Furthermore, higher histologic grade cancers and the HER2 overexpression-typetended to have lower elasticity scores.Conclusion The elasticity score of IDC had a significant correlation with LN involvement but no statisticallysignificant correlation with the histologic features, immunohistochemical markers or molecularsubtypes.