[Axillary treatment in breast cancer: surgery, radiotherapy, or none of these?]

The AMAROS trial showed that substituting axillary lymph node dissection by radiotherapy of the axillary and periclavicular nodes (ART) in patients with sentinel node (SN) metastases results in less lymphoedema, without a significant difference in the 5-year axillary recurrence rate (ARR). Three surgical studies showed no increase in ARR after omitting axillary treatment in cases of limited SN metastases, provided that adjuvant systemic therapy and tangential breast radiotherapy were applied. On the other hand, several recent radiotherapy trials, including a meta-analysis by the Early Breast Cancer Trialists' Collaborative Group, showed that regional radiotherapy improves disease-free survival where there are positive axillary nodes. In view of the low ARR and good overall survival with contemporary breast cancer treatments, limiting axillary treatment and its associated morbidity is a logical development. However, it is too early to omit axillary treatment in all SN-positive patients. ART is a safe next step in reducing axillary treatment.