To assess the value of combined percutaneous and transvenous contrast-enhanced ultrasound (CEUS) in the diagnosis of sentinel lymph nodes (SLN) in patients with breast cancer.

One hundred and seventy-four patients with breast cancer who underwent surgical treatment at Department of Breast Surgery of the Affiliated Hospital of Nanjing University of Chinese Medicine from November 2016 to June 2018 were selected. All patients underwent percutaneous CEUS for SLN localization, conventional ultrasound, and transvenous CEUS. Using the methylene blue staining method and pathological results as the standard, the effectiveness of conventional ultrasound and combined percutaneous and transvenous CEUS in diagnosing SLN was compared and analyzed.

The rates of methylene blue staining and percutaneous CEUS for locating SLN were 99.4% and 96.0%, respectively, and there was no significant difference between them (P=0.067). Pathological results showed that 56 out of 175 SLN had metastasis. The specificity, sensitivity, and accuracy of conventional ultrasound in diagnosing SLN were 71.4%, 64.3%, and 69.1%, respectively. The specificity, sensitivity, and accuracy of combined percutaneous and transvenous CEUS in diagnosing SLN were 84.0%, 76.8%, and 81.7%, respectively. The accuracy of combined percutaneous and transvenous CEUS in diagnosing SLN was significantly higher than that of conventional ultrasonography (Chi-square value=7.46, P＜0.05). According to the surgical and pathological characteristics, 175 SLN were divided into macrometastasis (n=38), micrometastasis (n=18), and non-metastasis groups (n=119). The accuracy of routine ultrasound in the diagnosis of SLN in the macrometastasis group, micrometastasis group, and non-metastatic group was 71.1%, 50.0%, and 71.4%, separately. The accuracy of combined percutaneous and transvenous CEUS in the diagnosis of SLN in these three groups was 86.8%, 55.6%, and 84.0%, separately.

Percutaneous CEUS is an important technique for localization of SLN before surgery. The combination of percutaneous and transvenous CEUS has good qualitative diagnostic value for SLN metastasis of breast cancer.