Since the 1970s, axillary dissection has been regarded primarily as a staging procedure, with a secondary purpose of maintaining local control in the axilla. The widespread administration of adjuvant systemic therapy to women with breast cancer, as well as the increasingly frequent detection of very small breast cancers by mammography, has prompted an examination of the need for axillary dissection in all women with invasive breast cancer. This article reviews the rationale for eliminating axillary dissection, the incidence of nodal metastases in small and apparently favorable breast cancers, and discusses how often the findings of axillary dissection actually alter therapy in patients with clinically node-negative breast cancers. The extent of axillary dissection necessary to provide accurate staging and maintain local control is examined, and patients who will benefit from axillary dissection are identified.
