Predictors of Pathologic Complete Response and Its Prognostic Value in Early Breast Cancer: A Real-World Cohort Study

HER2 positivity, high Ki-67, low ER expression, and radiologic complete response are independent predictors of pCR. Achieving pCR strongly correlates with improved DFS but not OS, likely due to limited sample size and event number. These findings reinforce pCR as a surrogate endpoint in TNBC and HER2-positive disease and highlight the need for post-neoadjuvant escalation in non-pCR patients.