Identification of HER2-Positive Breast Cancer Molecular Characterization and Subtypes

Inclusion criteria

• 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;
• Known estrogen receptor (ER) and progesterone receptor (PgR) status.
• Has adequate bone marrow, renal, hepatic and blood clotting functions.
• Left ventricular ejection fraction (LVEF) ≥50 percent (%).
• Women of childbearing potential and men with partners of childbearing potential must agree to use a highly effective form of contraception or avoid intercourse during and upon completion of the study and after the last dose for at least 7 months. Negative serum or urine pregnancy test within 7 days before study enrollment.
• Willing to provide tissue for research purposes.
• Volunteer to participate in this study and sign the informed consent.

Exclusion criteria

• 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)];
• Subjects had participated in clinical trials of other antineoplastic drugs within 4 weeks before the group;
• Has uncontrolled or significant cardiovascular disease.
• Allergy to any investigational drug or any ingredient or excipient in the drug;
• Female subjects who are pregnant, lactating or plan to become pregnant during the study.
• Has any other condition that per protocol or in the opinion of the investigator is inappropriate for the study.