This retrospective, non-interventional study is designed to assess the following primary objectives:
1. To identify predictors of event-free survival (EFS) in patients with HR+ and HER2-low/negative breast cancer treated with neoadjuvant chemotherapy or endocrine therapy, and
2. To stratify patients according to event-free survival using different combinations of significant predictors and evaluate the patient characteristics and clinical outcomes such as EFS, overall survival and pathological complete response across patient groups of different risk level.
