[Liver arterial infusion chemotherapy with adjuvant trastuzumab for the simultaneous treatment of liver and breast cancer-a case report].

A 62-year-old woman being treated for chronic hepatitis C and high blood pressure was shown by computed tomography to have tumors in the lateral and medial segments of her liver, and in her right breast. The tumor in the lateral segment of the liver was excised, the tumor in the medial segment of the liver was treated with microwave coagulation therapy, and the breast tumor was treated with simple mastectomy and sentinel lymph-node biopsy. Based on pathological features, the liver tumors were classified as moderately differentiated liver cell carcinoma, and the breast tumor as estrogen receptor-negative, progesterone receptor-negative, and human epidermal growth factor receptor-2-positive ductal carcinoma. Hepatic arterial infusion chemotherapy using fluorouracil and cisplatin with trastuzumab as an adjuvant was administered to treat both cancers simultaneously. Twelve months after the operation, neither of the cancers had relapsed. This case suggests that when the breast cancer is human epidermal growth factor receptor-2-positive, trastuzumab should be administered as adjuvant therapy.