This study will evaluate the safety and efficacy of neoadjuvant trastuzumab, pertuzumab and chemotherapy chosen by the investigators and identify the molecular characterization and subtypes in human epidermal growth factor receptor 2 (HER2)-positive breast cancer.
Age 18 - 75 years;
Eastern Cooperative Oncology Group (ECOG) score status 0-1.
Histologically confirmed invasive breast carcinoma with a primary tumor size of more than (>) 2 centimeters (cm) by standard local assessment technique; Breast cancer stage at presentation: early-stage (T2-3, N0-1, M0) or locally advanced (T2-3, N2 or N3, M0; T4, any N, M0);
HER2-positive breast cancer confirmed by immunohistochemistry or HER2 gene amplification by in situ hybridization;
Patients with stage IV metastatic breast cancer.
Bilateral invasive breast cancer;
Patients with breast cancer who have previously received anti-tumor therapy.
Occurred or present with other malignant tumors within 5 years. Patients with the following two conditions can be enrolled: other malignancies treated with a single operation, achieving continuous 5-year disease-free survival (DFS); Cured cervical carcinoma in situ, non-melanoma skin cancer and superficial bladder tumors [Ta (non-invasive tumor), Tis (cancer in situ) and T1 (tumor infiltrating basal membrane)];