Multicenter Prospective Study of Color Doppler Ultrasound for Breast Masses: Utility of Our Color Doppler Method

Abstract

The use of color Doppler ultrasound (CD) for distinguishing between benign and malignant breast lesions remains controversial. This study (JABTS BC-04 study) was aimed at confirming the usefulness of our CD diagnostic criteria. We evaluated ultrasound images of 1408 solid breast masses from 16 institutions in Japan (malignant: 839, benign: 569). Multivariate analysis indicated that vascularity (amount of blood flow), vascular flow pattern ("surrounding marginal flow" or "penetrating flow") and the incident angle of penetrating flow were significant findings for distinguishing between benign and malignant lesions. However, the sensitivity and specificity of B-mode alone did not improve significantly with CD addition (97.6% ! 97.9%, 38.3% ! 41.5%, respectively). We explored the causes of these negative results and found that age should have been considered when evaluating vascularity. Simulation experiments suggested that specificity is significantly improved when age is taken into consideration (38.3% ! 46.0%, p < 0.001) and we thereby improved our diagnostic criteria.

Clinical value and application of contrast-enhanced ultrasound in the differential diagnosis of malignant and benign breast lesions

“…Due to the atypical manifestations of breast cancer and the fact that breast cancer with a diameter of <2 cm is relatively difficult to identify by palpation, the disease is associated with relatively high mortality (3). Therefore, the early detection and treatment of breast cancer are of great importance to reduce the incidence and associated mortality (4). The imaging performance of breast cancer, particularly for small tumors, is complex and diverse, leading to ambiguous diagnostic imaging results (5).…”

Color Doppler Ultrasound Improves Machine Learning Diagnosis of Breast Cancer

“…Though the study aimed to determine the feasibility of diagnosing lesions utilizing these computer-extracted features, they are not intended to replace a radiologist’s readings, so BI-RADS US classification was retained as a feature. Additionally, a recent study by Watanabe et al found that differences in US between benign and malignant breast masses, especially in the vascularity revealed by CD, can depend on the patient’s age, supporting the selection of age as a feature [ 15 ].…”

“…Though utilizing CD for differentiating benign and malignant masses is not currently clinical standard practice, there is much evidence of its potential benefit. Previous studies have shown that CD improves the sensitivity and specificity of cancer diagnosis when utilized with GS US and clinical data [ 5 , 15 , 16 , 17 , 18 , 19 ]. This is thought to be because CD provides unique information on the direction and velocity of blood flow while also minimizing color artifacts.…”

“…Training on the two CD features, VFA and VI, improved the performance of the models, especially under the drop-rate pruning of indeterminate cases. In recent years, the improved resolution of CD has allowed heightened detection of blood flow in both benign and malignant masses [ 12 , 15 , 37 ]. This advance in CD technology could improve both the sensitivity and specificity of breast lesion diagnosis by machine learning.…”

“…Neoangiogenesis in breast lesions is also associated with increased speed of tumor growth and metastasis [ 14 ]. Although the assessment of vascularity can therefore improve breast cancer diagnosis using ultrasound [ 5 , 15 , 16 , 17 , 18 , 19 ], Doppler imaging is still underused in clinical applications. Since BI-RAD US grading does take Doppler images into account, there is scope for formalizing and quantifying Doppler assessment for improving breast mass diagnosis with radiomics.…”