Pegfilgrastim and Darbepoetin Alfa in Support of Adjuvant Chemotherapy for Breast Cancer

Inclusion Criteria: * Histologically or cytologically confirmed breast cancer clinical stage I, II or III disease. Patients must be deemed of sufficient risk for tumor or recurrence * Patients may receive the defined adjuvant chemotherapy treatment either following definitive breast surgery or prior to definitive breast surgery * 18 years of age or older * ECOG performance status 0 or 1 * ANC \> 1,500/uL * Hemoglobin \> 9 g/dL * Platelets \> 100,000/ul * Total bilirubin less than or equal to ULN * AST/ALT \< 1.5 x ULN * Creatinine within normal institutional limits * PT/PTT \< institutional upper limit of normal * LVEF \> 50% Exclusion Criteria: * Previous cytotoxic chemotherapy or therapeutic radiation therapy * Pregnant or lactating women * Receiving any other investigational agents * Stage IV breast cancer * History of allergic reactions attributed to compounds of similar chemical or biologic composition to pegfilgrastim or darbepoetin * Previous exposure to G-CSF or pegfilgrastim or to recombinant erythropoetin-related growth factors. * On antibiotics within 72 hours of registration * Patients with immune deficiency who are at increased risk of lethal infections when treated with marrow-suppressive therapy, or HIV-positive patients receiving anti-retroviral therapy * Sickle cell disease * Known positive antibody response to any erythropoietic agent * Known hematologic diseases * Known history of hyperviscosity syndrome * Patients on lithium * RBC transfusion within past 4 weeks