Reducing Neutropenia Incidence With Pegfilgrastim Administration on Day 3 After Chemotherapy

Inclusion Criteria: * Women aged 18 to 75 years old as of the date of study registration. * Patients with histologically confirmed invasive adenocarcinoma. * Patients with confirmed estrogen receptor, progesterone receptor, and Her2 receptor status. * Patients with Eastern Cooperative Oncology Group (ECOG) performance status 0-1. * Patients with a left ventricular ejection fraction (LVEF) ≥55%. * Patients who have agreed to participate in this trial and have provided written consent. Exclusion Criteria: * Patients with a history of breast cancer treatment * Patients with a history of chemotherapy, radiation therapy, immunotherapy, or biotherapy for malignancies other than breast cancer * Patients with infectious diseases * Patients with serious illnesses that may affect this clinical trial: cardiovascular disease, kidney disease, liver disease, endocrine disease, tumors, or diabetes * Other individuals deemed by the clinical trial investigators to be unable to participate in the trial.