[A case of elderly metastatic breast cancer with a complete response to treatment with capecitabine and cyclophosphamide].

We report a case of elderly metastatic breast cancer with a complete response to the treatment with XC (X: capecitabine and C: cyclophosphamide). A 78-year-old woman, who presented with left breast cancer, underwent pectoralis-preserving mastectomy when she was 76 years old. Pathological findings were as follows: invasive ductal carcinoma (scirrhous type), pT1c (2.0 cm), n (1/10), ly3, v1, ER (-), PgR (-), HER2: score 1. After one year and a half, a left supraclavicular lymph node metastasis, a left interpectoral lymph node metastasis, and mediastinal lymph nodes metastasis were noted. Capecitabine and cyclophosphamide were administered as first-line chemotherapy. After 8 cycles, all metastases responded, and this therapy is now being continued (19 cycles) on an outpatient basis. The complete response has continued for nine months. XC therapy can be the first-line chemotherapy for elderly metastatic breast cancer patients since it has been effective and no serious side effects have been encountered while maintaining quality of life.