We gave a presentation speaking about a practical approach on the management of the axilla after neoadjuvant chemotherapy and we spoke a little bit about management of the axilla in clinically node negative patients but really spent most of the time talking about unresolved clinical questions in the management of the axilla in clinically node positive patients.
We first discussed the prospective trials that have demonstrated that the false negative rate of sentinel lymph node biopsy in clinically node positive patients after neoadjuvant chemotherapy exceeded the 10% rate considered to be clinically acceptable but we knew that there were some things that could modify the false negative rate. So we spoke about the number of sentinel nodes retrieved and with three or more nodes removed the false negative rate fell to below 10%. Specifically, in a very recently published meta-analysis looking at the false negative rate associated with the number of sentinel nodes removed the false negative rate was 4% when three or more sentinel nodes removed. So we really highlighted that the importance of removing three or more sentinel nodes in clinically node positive patients after neoadjuvant chemotherapy.
We also spoke about the role of imaging after neoadjuvant chemotherapy to select patients for sentinel node biopsy and found that axillary imaging really is a poor predictor of residual disease in the axilla and that it should not be used to select patients for sentinel node biopsy. We also spoke about patients that were hormone receptor positive, HER2 negative and talked about which patients of those had the best response to neoadjuvant chemotherapy and specifically spoke about standard pathologic features that could help you select those patients that had the best response. The patients that were progesterone negative and had high grade or poorly differentiated tumours really had the best response to neoadjuvant chemotherapy and the remainder really perhaps should be considered for neoadjuvant endocrine therapy, they might have a better response to that.
We also finally spoke about controversial indications for axillary lymph node dissection and spoke about how sentinel lymph node biopsy should not be done in patients with locally advanced breast cancer; there is very limited data supporting its use. And also spoke about how in patients who had very low volume disease in the axilla after neoadjuvant chemotherapy that they have a high likelihood of having a residual burden of disease in the non-sentinel nodes, over 60%, and that axillary lymph node dissection is warranted in those patients.
We recognise that sentinel lymph node biopsy in clinically node positive patients we want to do it in a safer setting. We want to not leave behind potentially chemotherapy resistant disease and so the situations that we feel it’s appropriate are for patients with early stage operable breast cancer, clinical T1-3 N1 disease who become clinically node negative after neoadjuvant chemotherapy are the patients who we should be considering sentinel node biopsy in. Then if there’s residual disease in the nodes after neoadjuvant chemotherapy those patients should have an axillary dissection or if patients have locally advanced breast cancer they should not have sentinel node biopsy, they should proceed straight to an axillary dissection.