Objective imaging reporting and data system（BI-RADS）category 4 A lesions.MethodsConventional ultrasound and SWE data from 131 patients with 133 breast lesions which were classified as BI-RADS category 4 A were analyzed retrospectively.According to the pathological results

lesions were divided into two groups（110 lesions in benign group and 23 lesions in malignant group）. The maximum shear wave velocity（SWVmax）

minimum shear wave velocity（SWVmin）

shear wave velocity difference（ΔSWV）and elastic color pattern of each lesion were obtained.Taking pathological results as the gold standard

the ROC curve was drawn

and the area under the ROC curve（AUC）of different parameter was achieved.The parameters of SWE were combined with clinical data and conventional ultrasound features to construct a Logistic regression model

the diagnostic efficacy of this model was obtained and compared with the parameters of SWE.ResultsThere were statistically significant difference in patient’s age

the Adler blood flow grading

SWVmax

SWVmin

ΔSWV and elasitc color pattern between benign and malignant lesions（all P<0.05）.The ROC curve analysis showed that AUCs of SWVmax

SWVmin

ΔSWV and color pattern in distinguishing benign and malignant lesions were 0.767

0.643

0.755 and 0.780

the sensitivity were 65.2%

60.9%

69.6% and 69.6%

the specificity were90.0%

60.9%

86.4% and 86.4%

respectively.The AUCs of SWVmax

ΔSWV and color pattern were not statistically significant difference

but all higher than that of SWVmin（all P<0.05）.The Logistic regression analysis showed that patient’s age（X1）

the Adler blood flow grading（X2）and elastic color pattern（X3）were included in the equation

Logistic（P）=-7.579+1.078 X1+4.986 X2+7.376 X3.The AUC

sensitivity and specificity of the model were 0.864

78.3% and 90.9%

respectively

which were higher than each parameters of SWE alone（all P<0.05）.ConclusionSWE has a certain value in differential diagnosis of breast BI-RADS category 4 A lesions

especially SWVmax

ΔSWV and elastic color pattern shows a better diagnostic efficacy. The combination of elastic color pattern with patient’s age and the Adler blood flow grading could improve the detection rate of malignant lesions.