The primary endpoint of study-5-year disease-free survival (DFS) will be assessed by Kaplan Meier analysis. Secondary endpoints included overall survival and analysis of the prognostic and predictive value of clinical and molecular markers. Associations and interactions will be assessed with a multivariable Cox proportional hazards model for DFS for the following covariates: age, menopausal status, tumor size, lymph node status, type of chemotherapy, tumor size, positive lymph nodes, HER2 status, and hormone receptor status. All statistical tests will be two-sided.
