Omission of SLNB in CN0 Early Breast Cancer

All patients enrolled have to receive two or more imaging tests including axillary ultrasound assessed as axillary lymph node negative, and other tests including MRI, PET-CT, \[18F\]-FDG PET-MRI, axillary surgery will be omitted for eligible patients, and BCS or mastectomy (allowing breast reconstruction) will be chosen voluntarily by the patient under the premise of ensuring therapeutic efficacy, patients receiving BCS must undergo whole breast irradiation (WBI) after surgery, and the radiotherapy target area does not include the axillary region.