Sentinel lymph node biopsy does not apply to all axillary lymph node-positive breast cancer patients after neoadjuvant chemotherapy.

Background: The aim of this study was to investigate the feasibility of sentinel lymph node biopsy (SLNB) after neoadjuant chemotherapy (NAC) in breast cancer patients with confirmed axillary nodal metastases.

Methods: We enrolled 51 patients with breast cancer who received NAC. All patients were proven to have axillary nodal metastases by histopathology biopsy prior to NAC. They all underwent SLNB before breast surgery, and complete axillary lymph node dissection immediately followed.

Results: The identification rate for SLNB was 87.5% (84/96); the false negative rate was 24.5% (12/49). The clinicopathological factors were not significantly correlated with the identification and false negative rate of the SLNB. Lymphatic mapping, blue dye or radionuclide methods tended to decrease the identification rate of SLNB (P = 0.073). Clinical nodal status before NAC has a trend to increase the false-negative rates of the SLNB (P = 0.059). For patients with N1 clinical axillary lymph nodal status, the identification rate was 93.9%, and the false negative rate was 5.9%, compared with N2-3 patients with 73.9% and 38.9%, respectively.

Conclusions: SLNB is feasible for the patients whose axillary lymph nodal status before NAC is N1. However, for N2-3 patients, SLNB cannot be used as an infallible indicator of non-SLN status.