Preoperative factors that predict pathologic nodal involvement in early-stage HER2+ breast cancer: selecting cT1cN0 patients for treatment with neoadjuvant chemotherapy versus upfront surgery

The goal of this study was to identify the preoperative predictors of pathologic nodal metastases (pN+) in cT1cN0 HER2+ breast cancer undergoing upfront surgery. We retrospectively reviewed data from women with cT1-T2N0 HER2+ breast cancer treated with neoadjuvant therapy (NAC) or upfront surgery at our institution between 2012 and 2023. Factors associated with management strategy were evaluated, and in those undergoing upfront surgery, univariate analyses were performed to identify the clinicopathologic factors associated with nodal metastases. Overall, 255 women with cT1-T2N0 HER2+ breast cancer met inclusion criteria, including 170 (68.6