Ultrasound-Guided Restaging and Localization of Axillary Lymph Nodes After Neoadjuvant Chemotherapy for Guidance of Axillary Surgery in Breast Cancer Patients: Experience with Activated Charcoal

Objective: The aim of this study was to review our experience with ultrasound (US)-guided localization of axillary lymph nodes using activated charcoal for the guidance of axillary surgery after neoadjuvant chemotherapy (NAC) in clinically node-positive breast cancer patients. Methods: Between April 2016 and April 2017, US-guided localization of the most suspicious axillary lymph nodes at restaging US using activated charcoal (Charcotrace™) was performed in 45 consecutive, clinically node-positive breast cancer patients who had less than two suspicious nodes after NAC and axillary surgery with sentinel node biopsy. Sentinel nodes were defined as radioactive nodes or nodes containing blue dye. The concordance between final pathological results for both the tattooed and sentinel nodes was analyzed. Results: Sentinel node biopsy failed in five patients (11%) in whom axillary surgery was performed under the guidance of the tattooed node. The tattooed nodes were identified in the surgical field in 44 patients (98%). Of the 44 tattooed nodes, 25 (57%) were concordant with the sentinel nodes and 19 (43%) were non-sentinel nodes, including the five nodes with failed sentinel node biopsy. In the final pathological results, 18 patients (40%) had metastatic nodes. The sensitivities for detecting axillary metastasis of the sentinel node biopsy, tattooed node biopsy, and the sentinel and/or tattooed node biopsy were 61% (11/18), 67% (12/18), and 78% (14/18), respectively. Conclusion: US-guided localization of axillary lymph nodes using activated charcoal at restaging after NAC in clinically node-positive breast cancer patients is a useful technique to guide axillary surgery, with a high identification rate.