Factors that influence ultrasound evaluation of breast tumor size

To determine the factors influencing ultrasound breast tumor size assessment accuracy.

Five factors (tumor type, molecular subtype, histological size, histological grade, and breast density) were used to assess the measurement accuracy of breast ultrasound in tumor size. Size underestimation was defined as ultrasound index lesion diameter < histological size by at least 5 mm.

Breast ultrasound underestimated tumor size significantly, especially in cases with intraductal components (p=0.002). There was a tendency for higher size underestimation in breast cancer tumors with high-histological grade (p=0.03), human epidermal growth factor receptor type 2 (HER2)-overexpressing breast cancer tumors (p=0.02) and hormone receptor (HR)-/HER2+ breast cancer tumors (p=0.008). Furthermore, core biopsy revealedhigher probability of size underestimation with intraductal components (p=0.002). Size underestimation was more frequent with larger histological size (p<0.001). Masses in non-dense breasts were significantly underestimated (p=0.036) compared to dense breasts.

The size underestimation was influenced by pathological type, molecular subtype, and histological size. The pathological results of core biopsy were conducive for predicting tumor size pre-surgery in precise breast cancer diagnosis.