Updates in Surgical Management of the Axilla

Over the past 3 decades, axillary management in patients with breast cancer has evolved dramatically. The introduction and increasing use of sentinel lymph node biopsy (SLNB) have revolutionized the surgical approach for many patients with early breast cancer, permitting appropriate axillary staging without compromising prognosis and conferring significantly less morbidity than axillary lymph node dissection (ALND). For patients with clinically node-negative breast cancer and pathologically negative nodes or limited nodal metastases who have up-front surgery followed by radiotherapy, SLNB alone is now the standard of care, as it is for many patients who are clinically node positive and achieve a nodal pathologic complete response to neoadjuvant therapy. Omission of SLNB is also becoming possible for many patients with early-stage hormone receptor-positive/HER2-negative clinically node-negative breast cancer, with a large randomized trial demonstrating noninferiority of omission of axillary surgery to SLNB. Conversely, for those with residual nodal disease after neoadjuvant chemotherapy or those with a clinically positive axilla who have up-front surgery, ALND remains indicated, although clinical trials evaluating de-escalation of axillary surgery in these patient subsets are ongoing. As multidisciplinary treatment paradigms become increasingly nuanced, it is crucial that systemic therapy treatment decisions for patients with early-stage breast cancer be based on the available pathologic nodal status provided by SLNB, without the need for ALND to find additional positive nodes. Here we review recent advances and ongoing controversies in the modern surgical management of the axilla in breast cancer.