OBJECTIVES: I. Determine the maximum tolerated doses of mitoxantrone and cyclophosphamide when administered in combination with thiotepa, autologous blood cells, and amifostine in patients with primary, locally advanced, or metastatic breast cancer, and determine whether amifostine, a cytoprotection agent, allows administration of high dose chemotherapy. II. Determine the dose limiting toxicities of this regimen when administered to patients with primary, locally advanced, or metastatic breast cancer. III. Evaluate the toxicities of amifostine, a cytoprotection agent, when administered in multiple doses to breast cancer patients receiving high dose chemotherapy and autologous blood cell transplantation. IV. Document the antitumor efficacy of this regimen versus freedom from recurrence and overall survival after autologous blood cell transplantation. V. Assess the contribution of disease, treatment, and personal characteristics affecting the quality of life in these patients and the patient's primary caregiver.