SLNB has been recommended by domestic and foreign guidelines for patients with initial cN1 and NAC descending to ycN0. However, the best technical path is still not very clear at present, and the long-term tumor safety data is still insufficient. Therefore, it is necessary to further explore the optimal technical pathway and long-term tumor safety for SLNB in patients with initial cN1 and NAC downgrading to ycN0 in the real world.This study will evaluate the optimized technical pathway and long-term tumor safety of SLNB in patients with initial cN1 and NAC downgrading to ycN0 in real-world studies. The main endpoint of the study was axillary recurrence free survival. The secondary study endpoints were regional lymph node recurrence free survival, disease-free survival, overall survival, incidence of postoperative upper limb lymphedema, and patient quality of life.
