[Neoadjuvant treatment in human epidermal growth factor receptor 2-positive breast cancer]

Breast cancer is the most prevalent malignancy among females worldwide. Human epidermal growth factor receptor 2 (HER2)-positive breast cancer represents a subtype with aggressive behavior, poor response to treatment and unfavorable prognosis. Anti-HER2-based neoadjuvant treatment has improved clinical outcomes of patients with HER2-positive disease. Pathological complete response (pCR) after neoadjuvant treatment indicates a favorable prognosis. With the development of HER2-targeted therapy and neoadjuvant treatment, numerous studies focus on the predictive factors of pCR or therapeutic resistance of anti-HER2 therapy. Identification of novel predictive factors in HER2-positive breast cancer, such as tumor-infiltrating lymphocytes, will be helpful for clinical decision.