The value of conventional ultrasound combined with virtual touch tissue imaging in differentiating benign and malignant breast lesions

Abstract

Objective To discuss the value of conventional ultrasound combined with virtual touch tissue imaging (VTI) in differentiating benign and malignant breast lesions by breast imaging reporting and data system (BI-RADS) diagnostic criteria. Methods From January 2013 to October 2014, 395 breast lesions from 389 patients from the Tenth People's Hospital, Tongji University were included in present study. All the lesions were confirmed by surgery pathology. Conventional ultrasound and VTI examinations were done before surgery. Both benign and malignant lesions were classified into varied categories based on the boundary of lesions under VTI mode. Benign and malignant breast lesions were classified into BI-RADS categories by conventional ultrasound or conventional ultrasound combined with VTI. The χ2 test was used to compare the differences of lesions′ boundaries between VTI categories and VTI mode. The pathology findings were used as golden criteria, to calculate the sensitivity, specificity and accuracy of conventional ultrasound as well as conventional ultrasound combined with VTI. And their diagnostic performances were compared by McNemar′s test. Results Of 395 breast lesions, 282 (71.4%) were benign, 113 (28.6%) were malignant. 75.5% (213/282) benign lesions were classified as Ⅱ-Ⅲ under VTI mode, while 83.2% (94/113) malignant lesions were classified as Ⅳ-Ⅴ under VTI mode. The differences in classification between them was statistically significant (χ2=114.759, P<0.01). 77.7% (219/282) benign lesions had unclear boundaries under VTI mode, while 78.8% (89/113) malignant lesions had clear boundaries under VTI mode. The differences in boundaries between them was statistically significant (χ2=108.480, P<0.01). The sensitivity, specificity and accuracy of conventional ultrasound in differentiating benign and malignant breast lesions were 97.3%, 54.2% and 66.6% respectively; while the sensitivity, specificity and accuracy of conventional ultrasound combined with virtual touch tissue imaging in differentiating benign and malignant breast lesions were 98.2%, 84.4% and 88.4% respectively. The specificity and accuracy were higher when only using conventional ultrasound with statistical significance (χ2=79.425, 67.549, both P<0.01); however the sensitivity had no significantly different (χ2=11.974, P<0.01). Conclusion Conventional ultrasound combined with virtual touch tissue imaging can improve the specificity and the accuracy in differentiating benign and malignant breast lesions. Key words: Elasticity imaging techniques; Ultrasonography; Breast diseases; Diagnosis, differential