Participants undergo sentinel lymph node biopsy with intraoperative frozen section examination. Sentinel lymph nodes are identified using blue dye and a gamma probe, and intraoperative decision-making regarding additional axillary intervention is based on frozen section results.

Participants undergo sentinel lymph node biopsy without intraoperative frozen section. Sentinel lymph nodes are identified using blue dye and a gamma probe, then processed after formaldehyde fixation with routine histopathological evaluation. Further axillary treatment is decided according to final pathology and tumor board assessment.

Sentinel lymph nodes are rapidly transported to pathology without formaldehyde fixation and are evaluated intraoperatively by frozen section.

Count of participants randomized by sealed-envelope method to either intraoperative frozen section evaluation of sentinel lymph nodes or routine histopathological evaluation after formalin fixation. This outcome will be reported as the total number of randomized participants until the protocol-defined target sample size for between-group comparison is reached (planned total sample size: 142 participants).

Percentage of participants assigned to the routine histopathology group without intraoperative frozen section who require axillary lymph node dissection based on final histopathological evaluation and multidisciplinary treatment decision.