What is the role of neo-adjuvant chemotherapy in triple positive cT1c N0 breast cancer especially after recent data from KATHERINE trial?

This is an interesting issue, and one discussed by Dan Hayes in his NEJM editorial accompanying the KATHERINE publication.

T1cN0 triple positive disease in the original trial of adjuvant paclitaxel/traztuzumab x 12 weeks (Tolaney, NEJM 2016) had a 4 year EFS in excess of 97%. Therefore I am not sure that the absolute benefit of TDM-1 (while likely to be some small number) in the setting of residual disease that is T1cN0 is substantial enough to push me to give NAT in this setting. I generally hav...