Neoadjuvant therapy and sentinel lymph node biopsy in HER2-positive breast cancer patients: results from the PEONY trial.

For clinical ALN negative patients, HER2-positive subtype is found to have high node negative rate by pathology and it is recommended to undergo SLNB after NAT. For patients with positive ALNs who convert to negative, the false-negative rate is high. Dual tracer mapping, more than 2 SLNs detected, more than 1 SLN identified plus the clips placed are the guarantees for lower false-negative rate.