Minimally Invasive Sentinel Lymph Node Biopsy Using CEUS and Methylene Blue Injection

Overview

This study evaluates the combined use of preoperative contrast-enhanced ultrasound (CEUS) with intra-lymph node methylene blue (MB) injection and intraoperative indocyanine green (ICG) for sentinel lymph node (SLN) detection in early breast cancer. The dual-tracer approach demonstrated improved SLN identification rates and reduced false negative rates compared to traditional blue dye methods.

Background

Breast cancer is the most common malignancy affecting women worldwide, with axillary lymph node (ALN) status being a critical prognostic factor. Sentinel lymph node biopsy (SLNB) has replaced axillary lymph node dissection (ALND) in clinically node-negative patients to minimize surgical complications. Traditional SLN detection methods include blue dye and radioisotope tracers, but these have limitations such as allergic reactions, high costs, and radiation exposure. Contrast-enhanced ultrasound (CEUS) offers a non-radioactive, real-time preoperative imaging alternative, while methylene blue (MB) remains a widely used dye despite some drawbacks. Combining CEUS with MB and ICG fluorescence aims to enhance SLN detection accuracy.

Data Highlights

Key Findings

• Preoperative CEUS combined with intra-lymph node MB injection significantly improves SLN identification rates compared to blue dye alone.
• The dual-tracer method reduces the false negative rate, enhancing diagnostic accuracy for axillary staging.
• CEUS provides real-time visualization of lymphatic channels and SLNs before surgery, aiding surgical planning.
• ICG fluorescence during surgery complements CEUS and MB, facilitating precise intraoperative SLN localization.
• The combined approach minimizes complications associated with axillary lymph node dissection.

Clinical Implications

Integrating preoperative CEUS with intra-lymph node MB injection and intraoperative ICG fluorescence offers a minimally invasive, accurate method for SLN detection in early breast cancer. This dual-tracer strategy can reduce false negatives and surgical complications, potentially improving patient outcomes and aligning with precision medicine principles. Clinicians should consider adopting this approach to enhance SLNB efficacy, especially in settings where radioisotope use is limited.

Conclusion

The combination of CEUS, methylene blue injection, and ICG fluorescence represents a promising minimally invasive technique for sentinel lymph node detection, improving identification rates and reducing false negatives in breast cancer patients. This approach may optimize surgical management and reduce morbidity associated with axillary procedures.

References

1. National Comprehensive Cancer Network Guidelines -- Breast Cancer, 2024
2. Bracco Imaging SpA -- SonoVue Contrast Agent, 2023
3. Jumpcan Pharmaceuticals -- Methylene Blue Usage, 2023