Effectiveness of pazopanib for postoperative recurrence of granulocyte colony-stimulating factor-producing primary hepatic angiosarcoma

A 38-year-old Japanese woman was referred to our hospital with complaints of fever, general fatigue, and upper abdominal discomfort. Computed tomography revealed a massive tumor in the right lobe of the liver, and laboratory data demonstrated increased white blood cell (WBC) count and serum granulocyte colony-stimulating factor (G-CSF) level. An extended right hepatectomy was performed, and pathological examination revealed spindle-shape tumor cells that formed vessel-like structures that were compatible with hepatic angiosarcoma. As a rapid recurrence occurred after surgery, S-1 was administered as a first-line chemotherapy, and weekly paclitaxel was administered as the second-line chemotherapy. However, patient eventually became resistant to these therapies. Therefore, pazopanib, a multitargeted tyrosine kinase inhibitor, was administered, after which both the WBC count and G-CSF level rapidly decreased. 18F-fluorodeoxyglucose positron emission tomography (FDG-PET) revealed decreased FDG uptake. This is the first report on the administration of pazopanib as a third-line chemotherapeutic agent for treating G-CSF-producing primary hepatic angiosarcoma. The efficacy of this therapy was demonstrated with FDG-PET.