Background: Here we report a case of complete response in patient with Metastatic Breast Cancer treated by metronomic Chemotherapy. Case presentation: A 51 years old woman underwent righy mastectomy in may 2008. She performed firstline chemotherapy with doxorubicin every 21 days. The CT revaluation after ten cycle showed a partial response to treatment. It was decided to stop the treatment with doxorubicin and to start a metronomic therapy with cyclophosphamide 50 mg daily orally and Methotrexate 2.5 mg twice daily. After two months of this maintenance treatment, the CT scan showed a complete response. The metronomic treatment is still ongoing, and after 45 months the patient maintains a complete response..