The prognosis for patients with metastatic breast cancer remains poor. Metastatic breast cancer confined to the bones may have a better prognosis, especially hormone receptor-positive disease. We performed a prospective, randomized clinical trial to compare immediate consolidation with high-dose chemotherapy and hematopoietic support versus observation with high-dose consolidation at the time of disease progression in women with metastatic breast cancer and only bone metastases. The patients received chemotherapy with doxorubicin, 5-fluorouracil and methotrexate before randomization. In all, 85 patients were enrolled and 69 were randomized. The median follow-up is 8.1 years from randomization. The median event-free survival (EFS) for the immediate transplant arm is 12 months and for the observation arm is 4.3 months (P<0.0001). The median overall survival for the immediate transplant arm is 2.97 years and for the observation arm 1.81 years, a difference that is not statistically significant. Immediate high-dose chemotherapy and radiation therapy as consolidation offers a clinically and statistically significant improvement in EFS compared with radiation therapy alone following induction chemotherapy for women with metastatic breast cancer confined to the bones.