Preoperative contrast-enhanced ultrasound combined with intra-lymph node methylene blue injection for sentinel lymph node identification: a minimally invasive sentinel lymph node biopsy tracing approach
摘要
To investigate the significance of preoperative contrast-enhanced ultrasound (CEUS) coupled with injections of methylene blue (MB) into the lymph nodes, alongside intracutaneous injections of indocyanine green (ICG) for sentinel lymph node (SLN) identification in early breast cancer.
Materials and methodsAll patients from a single institution were prospectively randomized into two groups: CEUS Group (preoperative SLN-CEUS coupled with injections of MB into the lymph nodes, with ICG intracutaneous injections for SLN identification during surgery) and Blue Staining Group (intracutaneous injections of both ICG and MB for SLN mapping during surgery). Pathological results served as the gold standard. Multivariate logistic regression analysis was used to identify independent risk factors for SLN metastasis. Areas under the receiver-operating characteristic curve (AUC) were used to evaluate the ability of CEUS to diagnose SLN metastasis.
Results134 patients were enrolled (CEUS Group: 76 patients, Blue Staining Group: 58 patients). CEUS Group achieved a 100.0% success rate in detecting SLNs, with identifying a median of 1 SLN, while Blue Staining Group identifying a median of 4 SLNs per case (p < 0.001). CEUS enhancement pattern was the only factor independently linked to SLN metastasis (p < 0.001), showing a sensitivity of 90.5% and a specificity of 94.5%. The AUC for identifying SLN metastasis was 0.925.
ConclusionsCEUS enhancement pattern is helpful to determine the SLN metastasis. Preoperative CEUS, combined with MB injections into lymph nodes and intracutaneous ICG injections during surgery, provides a reliable method for localizing SLNs. This approach minimizes the risk of non-SLNs excisions.
Key Points