Contemporary management of the axilla in breast cancer.

The care of patients with breast cancer in the modern era involves a multimodal approach to treating locoregional and distant disease. Recent studies have demonstrated that the extent of surgical intervention in both the breast and axilla can be minimized through a personalized approach based on breast cancer stage, subtype, and planned adjuvant therapies. The older approach focused on complete removal of the axillary contents for appropriate staging and to determine the need for adjuvant systemic therapy and radiation. This approach has been replaced by sentinel lymph node biopsy, which allows for axillary staging with the removal of only the nodes most likely to contain metastatic disease. Sentinel lymph node biopsy obviates the need for complete axillary lymph node dissection in patients with node-negative disease. Clinical trials have also shown that axillary dissection can be avoided in those patients with low axillary disease burden in the sentinel nodes who are undergoing breast-conserving therapy. Radiation can also be used as an alternative to axillary dissection in patients with positive sentinel nodes, without increasing the risk for regional recurrence. Further studies are needed in patients undergoing mastectomy to determine the optimal strategy for axillary management in the setting of limited disease in the sentinel nodes. The use of neoadjuvant chemotherapy allows the ability to evaluate an individual tumor's response to therapy, thereby increasing the possibility of breast-conserving surgery and reduction in the extent of axillary surgery. This review will explore the evolution of management of the axilla in patients with clinically node-negative and node-positive disease, and will provide insights into future directions in breast cancer care.