All patients received AC regimen (epirubicin or pirarubincin in combination with cyclophosphamide) intravenously. Epirubicin 90mg/m^2 (or pirarubicin 60mg/m^2) and cyclophosphamide 600mg/m^2 were administered on day 1 of the chemotherapy cycle. AC regimen was administered bi-weekly or 3-weekly.~Eligible patients were randomly assigned to 3mg arm (the study arm) and 6mg arm (the control arm) in a 1:1 ratio, stratified according to body weight (≤60kg or >60kg). Patients in the study arm and the control arm received a subcutaneous injection of 3mg PEG-rhG-CSF and 6mg, respectively, forty-eight hours after completing chemotherapy infusion.
Pegfilgrastim is a long-acting recombinant human granulocyte-colony stimulating factor as support for chemotherapy, which can be used conveniently.~According to the package inserts in America, Europe, and China, the recommended dose for pegfilgrastim is 6mg per cycle, while it is recommended at a dose of 3.6mg in Japan. It is still unclear whether pegfilgrastim 3mg can produce similar efficacy with pegfilgrastim 6mg.~In this trial, the investigators prospectively compared the efficacy and safety of pegfilgrastim 3mg with 6mg in patients with breast cancer receiving AC regimen, a commonly used regimen in adjuvant chemotherapy for breast cancer.