Delayed SLND for Patients With Breast Cancer Undergoing Primary Systemic Treatment

The goal of this study was to assess the feasibility of SLND by superparamagnetic iron oxide nanoparticles (SPIO) in patients with early breast cancer planned for primary systemic therapy (PST) and whether this is affected by the timeframe of SPIO administration. For this, patients with cN0/1 disease planned for PST received radioisotope as per routine on the day of surgery or the day before, and SPIO was injected in an extended timeframe, at any point from the day of surgery to before the induction of PST. The main points to investigate are: 1. If the SPIO detection rate and concordance to the radiosotope are affected by time of SPIO injection 2. If the nodal yield and the accuracy of the procedure are affected