A Case of Metastatic Malignant Phyllodes Breast Tumor Showing Long-term Disease Control by Eribulin and Pazopanib

Abstract

The patient, a 59-year-old woman, had been diagnosed with a giant malignant phyllodes tumor and treated by mastectomy at 56 years of age. For treatment of lung metastases detected 6 months after the surgery, she was started on eribulin. Doxorubicin was not selected because of poor control of diabetes. The patient received long stable disease for 9 months and had no major adverse event except Grade 1 hair loss. After one year, she developed disease progression, with metastases in the lung and in the formerly unaffected liver. Subsequently, pazopanib was selected for the metastatic malignant phyllodes tumor. The patient was responsive to pazopanib for more than 18 months and had no major adverse events, except hypertension, Grade 1∼2 diarrhea, and dysgeusia. Recently, attention has been paid to eribulin and pazopanib, instead of doxorubicin, for the treatment of malignant soft tissue tumors. However, there were few reports of eribulin and pazopanib for malignant phyllodes tumors. In this case, eribulin and pazopanib proved to be useful treatment options for malignant phyllodes tumor, with high tolerance and long-term clinical benefit.