Background: Accurate sentinel lymph node (SLN) characterization is essential for breast cancer management, prompting advancements in imaging technologies such as contrast-enhanced ultrasound (CEUS) and sound touch quantification (STQ) to enhance diagnostic precision.
Objective: To explore the value of perfusion characteristics evaluated by CEUS combined with STQ parameters in diagnosing the properties of sentinel lymph node (SLN) in breast cancer.
Methods: A total of 91 breast cancer patients (91 SLNs) admitted to the hospital from February 2022 to December 2023 were selected for this study. Among them, 26 patients with metastatic SLN confirmed by surgery and pathology were included in the metastatic SLN group, and 65 patients with non-metastatic SLN were included in the non-metastatic SLN group. Preoperative examination results of CEUS and STQ were retrospectively analyzed. The diagnostic efficacy of perfusion characteristics evaluated by CEUS and STQ parameters for the properties of SLN in breast cancer was analyzed using the receiver operating characteristics (ROC) curve. Statistical methods such as chi-square tests and logistic regression analysis were employed to analyze the data.
Results: Enhancement patterns differed significantly between the metastatic SLN and non-metastatic SLN groups (p< 0.05). ROC curve analysis indicated that CEUS perfusion characteristics had an AUC value of 0.823 for diagnosing SLN properties, with a sensitivity of 84.62% and specificity of 70.77% using type I as the critical value. Additionally, STQ measurement showed significantly higher values in the metastatic SLN group (44.18 ± 6.53 kPa) compared to the non-metastatic SLN group (34.69 ± 6.81 kPa) (t= 6.075, p< 0.001). The AUC value for STQ parameters in diagnosing metastatic SLN was 0.849, with a sensitivity of 73.08% and specificity of 92.31% using 42.40 kPa as the critical value. Though the AUC value of STQ measurement was higher than CEUS perfusion characteristics alone, the difference was not statistically significant (Z= 0.393, p= 0.695). Moreover, combining CEUS perfusion characteristics with STQ parameters yielded an AUC value of 0.815 for diagnosing SLN properties, showing no significant difference compared to diagnosis with CEUS or STQ parameters alone (Z= 0.149, 0.516, p= 0.882, 0.606).
Conclusion: Combined use of perfusion characteristics evaluated by CEUS and STQ parameters can significantly improve the diagnostic specificity of SLN in breast cancer. It is worthy of clinical promotion.
Keywords: Breast cancer; contrast-enhanced ultrasound; diagnosis; sentinel lymph node; sound touch quantification.