Axillary management in breast cancer: what's new for 2012?

Sentinel lymph node (SLN) biopsy has become standard care for management of the axilla in invasive breast cancer, replacing axillary lymph node dissection (ALND) in most subjects, with a progressively diminishing role of ALND. Advances in preoperative imaging have also changed the algorithm for axillary management, and ultrasound-guided needle biopsy has been shown to triage >50% of subjects with node metastases to ALND. However, the past two years have witnessed remarkable and practice-changing advances in our knowledge and approach to management of the axilla, with availability of high-level evidence that demands reappraisal of practice and challenges the role of routine ALND for SLN-positive patients. In particular, for the group of patients defined by eligibility criteria in the Z0011 trial, it appears that ALND has little or no effect on local recurrence and survival, or on the choice of local or systemic therapies. We review the available evidence on staging and management of the axilla in breast cancer, and outline our interpretation of its implications for clinical practice.