A Phase III Study of High-Dose Chemotherapy Using Busulfan, Melphalan and Thiotepa Versus Cyclophosphamide,Thiotepa, Carboplatin Followed by Autologous Stem Cell Transplantation in Patients With High-Risk Primary Stage II or III (Non-Inflammatory) Breast Cancer

OBJECTIVES: I. Compare early mortality, survival, and disease free survival in patients with node positive stage II or IIIA breast cancer treated with busulfan, melphalan, and thiotepa versus cyclophosphamide, thiotepa, and carboplatin followed by autologous peripheral blood stem cell transplantation. II. Compare the toxicity of these 2 regimens in this patient population. OUTLINE: This is a randomized study. Patients are stratified according to stage of disease (stage II vs stage IIIA), lymph node status (at least 10 positive nodes vs less than 10 positive nodes), and hormone receptor status (estrogen receptor positive or progesterone receptor positive vs estrogen receptor negative or progesterone receptor negative). All patients initially receive mobilization chemotherapy with cyclophosphamide IV over 1-2 hours on day 1 and paclitaxel IV over 4 hours on day 2. Beginning on day 4, patients receive filgrastim (G-CSF) or sargramostim (GM-CSF) subcutaneously each day until the final day of leukapheresis. When blood counts recover, peripheral blood stem cells (PBSC) are harvested. Patients are randomized to 1 of 2 high dose chemotherapy regimens 28-45 days after the last dose of mobilization chemotherapy. Arm I: Patients receive oral busulfan every 6 hours on days -8 to -6, melphalan IV over 30-60 minutes on days -5 and -4, and thiotepa IV over 2 hours on days -3 and -2. PBSC are reinfused on day 0. Arm II: Patients receive cyclophosphamide, thiotepa, and carboplatin by continuous IV infusion over 24 hours on days -7, to -4. PBSC are reinfused on day 0. Beginning 4-6 weeks after the last dose of chemotherapy, patients in both arms receive local radiotherapy 5 days each week for 5 weeks. Patients also receive oral tamoxifen (or equivalent antiestrogen therapy) daily for 5 years if they are estrogen or progesterone receptor positive, postmenopausal, or age 50 and over and perimenopausal. Patients are followed every 3 months for 2 years and then every 6 months thereafter. PROJECTED ACCRUAL: A total of 280 patients (140 per treatment arm) will be accrued for this study over 3 years.