Breast cancer subtypes affect the nodal response after neoadjuvant chemotherapy in locally advanced breast cancer: are we ready to endorse axillary conservation?

We evaluated the impact of breast cancer subtypes on pathologic complete response (pCR) in 181 patients with positive nodes undergoing neoadjuvant chemotherapy (NAC). After NAC, patients underwent surgery, with sentinel lymph node biopsy (SLNB) or axillary dissection (ALND). In 28.2% of cases a pCR was achieved, with the highest rate in Her2+ and triple negative tumors. Overall, nodal pCR was more frequent than breast pCR (P = 0.003) with higher percentages in Her2+ and LLB-Her2+ (P < 0.05). In the Her2+ group, nodal pCR was observed only with breast pCR. Thus, in Her2+ tumors, breast pCR predicts node pCR, supporting the use of SLNB in this subgroup to stage the axilla avoiding ALND.