A Case of Bilateral Breast Cancer with Severe Liver Dysfunction Caused by Simultaneous Liver Metastasis in which Chemotherapy could be Continued by Adjusting the Paclitaxel Dose

Docetaxel and paclitaxel (PTX) are key drugs in human epidermal growth factor receptor type 2 (HER2) positive metastatic/recurrent breast cancer. However, there is little information on the recommended doses for liver dysfunction. We performed trastuzumab/pertuzumab/PTX combination therapy (50 ％ dose of PTX) for patients with HER2-positive breast cancer who had Child-Pugh C liver dysfunction due to multiple liver metastases. After the chemotherapy, the patient ʼ s liver function improved rapidly, so the dose of PTX was increased to 75 ％ . However, since febrile neutropenia (FN) occurred, PTX was continued at a dose of 50 ％ thereafter. As a result, the patient was able to continue chemotherapy without FN. This case will help us consider the administration method of PTX in the case of severe liver dysfunction.