Axillary clearance in operable breast cancer: still a necessity?

Complete axillary dissection, as part of radical mastectomy, was the standard of care for the first three-quarters of this century. Long-term follow-up of these patients showed substantial cure rates for positive-node patients before systemic therapy was available, indicating a therapeutic value to nodal dissection. There was also good control of the axilla; axillary recurrence after removal of positive nodes was quite low. Even today, in patients with positive nodes, complete axillary clearance as part of a modified radical mastectomy or a breast conservation approach with lumpectomy leads to control of the axilla and complete axillary staging, allowing medical oncologists to tailor their systemic treatment to the total number of nodes involved. Today, due to a combination of factors including patient awareness and the ability of mammography to detect smaller lesions, many women present with small cancers that carry a much lower risk of axillary involvement. Whereas a complete dissection is indicated for patients with clinically involved nodes, a level I-II dissection is the standard in most centers for patients with clinically negative nodes. In those patients with very small (T1a, T1b) cancers, the role of sentinel lymphadenectomy is being explored; it may spare these patients the morbidity of complete axillary dissection.