Top Line: Is it safe to do sentinel lymph node biopsy after neoadjuvant chemotherapy for breast cancer patients with locally advanced T4 or N2-3 breast cancer?
The Study: Multiple prospective trials have established that SLNB is feasible after nCT for node positive breast cancer, and the false negative rate is <10% dual tracer mapping is used and 3 or more nodes are retrieved. However, these trials largely included cN1 disease with little if any representation from those with more advanced primary or nodal disease. This trial enrolled 145 patients with locally advanced breast cancer (cT4 or cN2-3 at presentation) who had a clinical complete response after neoadjuvant systemic therapy, and this included 44% with inflammatory breast cancer and 21% with cN3 disease. Patients underwent SLNB with dual tracer mapping followed by axillary lymph node dissection. A sentinel lymph node was identified in 74%, which is lower than the ~90% rate seen with prior trials with less advanced disease. Adequate mapping, which was defined as 3 or more sentinel nodes or 1-2 sentinel nodes with at least 1 clipped node was achieved in just 60%. This suggests more altered lymphatics from heavier disease burden, and a large subset of patients still require ALND for nodal staging. The nodal pathologic complete response rate was 46%, and among those with adequate mapping, the false negative rate was just 2.1%.
TBL: In this trial, the false negative rate from an adequately mapped SLNB after neoadjuvant therapy was very low for patients with locally advanced breast cancer. However, a quarter of patients did not have adequate sampling, and the overall population of patients with adequate nodal mapping was relatively small. | Barrio, J Clin Oncol 2026
The Study: Multiple prospective trials have established that SLNB is feasible after nCT for node positive breast cancer, and the false negative rate is <10% dual tracer mapping is used and 3 or more nodes are retrieved. However, these trials largely included cN1 disease with little if any representation from those with more advanced primary or nodal disease. This trial enrolled 145 patients with locally advanced breast cancer (cT4 or cN2-3 at presentation) who had a clinical complete response after neoadjuvant systemic therapy, and this included 44% with inflammatory breast cancer and 21% with cN3 disease. Patients underwent SLNB with dual tracer mapping followed by axillary lymph node dissection. A sentinel lymph node was identified in 74%, which is lower than the ~90% rate seen with prior trials with less advanced disease. Adequate mapping, which was defined as 3 or more sentinel nodes or 1-2 sentinel nodes with at least 1 clipped node was achieved in just 60%. This suggests more altered lymphatics from heavier disease burden, and a large subset of patients still require ALND for nodal staging. The nodal pathologic complete response rate was 46%, and among those with adequate mapping, the false negative rate was just 2.1%.
TBL: In this trial, the false negative rate from an adequately mapped SLNB after neoadjuvant therapy was very low for patients with locally advanced breast cancer. However, a quarter of patients did not have adequate sampling, and the overall population of patients with adequate nodal mapping was relatively small. | Barrio, J Clin Oncol 2026