Comparing single or dual tracing modality on sentinel lymph node biopsy from patients who plan to omitting axillary lymph node dissection referring to the criteria of Z0011 trial: a retrospective study

Axillary lymph node dissection (ALND) can be omitted in the part of the breast-conserving patients with positive sentinel lymph nodes (SLNs) since Z0011 trial has presented. Nevertheless, to date, no studies revealed the influence of different tracing modalities (single tracer versus dual tracers) for sentinel lymph node biopsy (SLNB) on axillary management referring to Z0011 trial criteria. This study aimed to assess whether different tracing modalities of SLNB have impact on axillary management referring to Z0011 trial criteria. The clinical data of breast-conserving patients who underwent SLNB guided by combination of methylene blue (MB) and indocyanine green(ICG) were retrospectively analyzed in our center. The numbers of metastatic (positive) SLNs guided by the single tracer and the dual tracer were compared by self-control study. 127 patients with 1–2 metastatic SLNs dyed by MB [(recorded as MB(+))]were retrieved from our database between 2016 and 2020. In these cases, 53 patients contained 86 SLNs, which were ICG staining but MB negative staining (recorded as ICG(+)/MB(−)). In addition, 16 patients contained 20 metastatic SLNs with ICG(+)/MB(−). There were six patients finally excluded patients (6/127, 4.7%) who initially met the criteria of Z0011 trial, because the further detection of ICG(+)/MB(−) SLNs led the total numbers of positive SLNs over two. The difference was statistically significant. Single tracing modality may underestimate the positive SLN numbers compared to dual tracing modality. Different tracing modalities of SLNB will significantly affect Axillary management referring to Z0011 trial criteria.