Abstract: Sentinel lymph node biopsy (SLNB) has become the standard technique for axillary staging in breast cancer, promoting a more individualized approach to axillary surgery. This review discusses several current emerging issues in SLNB for patients with breast cancer: inpatients with 1-2 positive sentinel lymph nodes (SLNs), studies such as SENOMAC have reinforced the safety of omitting axillary lymph node dissection (ALND), although careful consideration remains necessary for patients with abnormal axillary imaging findings and in the context of post-operative regional nodal radiotherapy strategies. Omission of SLNB may be appropriate in early-stage patients with clinically and radiologically negative axilla under strictly defined conditions to further minimize surgical trauma. In parallel, techniques for SLNB after neoadjuvant therapy continue to advance, with tumor safety outcomes becoming increasingly reliable, and the dual de-escalation of both surgery and radiotherapy may be anticipated. In addition, regional lymph nodes serve not only as the initial site of tumor metastasis but also as critical hubs of the adaptive immune response, positioning SLNs a potential window into tumor immune surveillance.