Management of the axilla after neo-adjuvant chemotherapy for breast cancer: Sentinel node biopsy and radiotherapy considerations.

Preoperative or neo-adjuvant chemotherapy in the management of breast cancer is a treatment approach that has gained in popularity in recent years. However, it is unclear if the treatment paradigms often employed for patients treated with surgery first hold true for those treated with preoperative chemotherapy. The role of sentinel node biopsy and the data supporting its use is different for those with clinically negative and clinically positive nodes prior to chemotherapy. For clinically node-negative patients, sentinel node biopsy after neo-adjuvant chemotherapy may be appropriate. For those node-positive patients whose axillary disease resolves clinically, the false-negative rate of the sentinel node biopsy is high. However, there are measures that can reduce that rate. After surgery, the radiation oncologist is often faced with complicated decisions surrounding the optimal radiotherapy in this setting. Tailoring radiation plans based on chemotherapy response holds promise and is the subject of ongoing clinical trials. In the accompanying article, we review the current literature on both surgery and radiation in axillary management and describe the interplay between these two treatment modalities. This highlights the need for multidisciplinary management in making treatment decisions for patients treated in this manner.