Dalpiciclib: China's Targeted New Drug, Guarding Hope for Breast Cancer Patients Among malignant tumors affecting women, breast cancer consistently ranks first in incidence. Approximately 70% of cases are hormone receptor (HR)–positive and human epidermal growth factor receptor 2 (HER2)–negative. Endocrine therapy is the cornerstone of treatment for this subtype; however, patients with advanced disease frequently develop resistance, leading to a major...