OUTLINE: This is a randomized study. Patients are stratified by estrogen receptor status and menopausal status. Within 6 weeks of surgery, patients in the first group receive epirubicin (preferred) or doxorubicin plus cyclophosphamide every 3 weeks for 4 courses followed by conventional cyclophosphamide, methotrexate, and fluorouracil (CMF) every 4 weeks for 3 courses. Patients in the second group undergo stem cell mobilization and harvest with granulocyte colony-stimulating factor (G-CSF) followed within 10 weeks of surgery by high-dose chemotherapy with epirubicin and cyclophosphamide followed by peripheral blood stem cell rescue and G-CSF. All patients receive adjuvant tamoxifen, and patients who underwent lumpectomy prior to entry are required to receive adjuvant radiotherapy (radiotherapy is optional for patients who underwent mastectomy prior to entry). Patients are followed every 3 months for 2 years, then q 6 months for 3 years, then yearly.