RESUMEN
Breast cancer is one of the most common cancers in women. Even if appropriate treatments are applied, metastasis can occur in any organ of the body. Uterine metastasis from an extrapelvic tumor such as breast cancer is very rare. A 62-year-old woman with breast cancer was treated with modified radical mastectomy after neoadjuvant chemotherapy and adjuvant chemoradiotherapy. A single lung metastasis developed at 2 years after surgery, and the patient underwent wedge resection followed by capecitabine chemotherapy. Afterwards, the patient was treated with gemcitabine/vinorelbine chemotherapy for skin metastasis. Recently, she complained of vaginal spotting for 3 weeks. MRI of the uterus revealed a 1.1 cm endometrial tumor with myometrial invasion. Biopsy confirmed papillary carcinoma that originated from previous breast cancer. Although she was treated by palliative radiotherapy to the uterus, docetaxel/cyclophosphamide and trastuzumab, disease progression was observed.