The procedure will consist of marking the pathological lymph node with 1 clip before the start of neoadjuvant chemotherapy (NAC) and performing surgery after completing the NAC. The TAD will include the exeresis of the node marked with a clip, and of the sentinels marked with technetium and/or patent blue, seeking to obtain at least 3 lymph nodes. Subsequently, the axillary lymphadenectomy will be completed to identify the false negative rate. An initial analysis will be carried out with the first 30 cases, and if there are more than 2 false negative cases, it will be completed until 81 cases of TAD without associated disease are obtained.
This is an observational study to validate target axillary dissection (TAD) in locally advanced tumors (cN2 and/or cT4).