The use of axillary ultrasound (AUS) to assess the nodal status after neoadjuvant chemotherapy (NACT) in primary breast cancer patients.

Introduction: Axillary Ultrasound (AUS) is standard for pre-therapeutic axillary staging in early breast cancer patients. 35-75 % of the breast cancer (BC) patients with positive axillary lymph nodes receiving neoadjuvant chemotherapy (NACT) convert to pathological node negative. For those patients, axillary surgery after NACT could be de-escalated, if an accurate prediction of the pathologic nodal status following NACT was possible.