Undifferentiated embryonal sarcoma is a rare primary malignant neoplasm of the liver. Undifferentiated sarcoma of the liver in adult is an uncommon hepatic tumor of mesenchymal origin, generally considered an aggressive neoplasm with an unfavorable prognosis. We present a case of undifferentiated sarcoma in a 61-year-old woman. CT scan demonstrated a large heterogenous, exophytic growing hepatic mass in the right lobe with pulmonary metastatic nodules. US guided liver biopsy was done and pathological findings of the liver specimen revealed that isolated or grouped round pleomorphic cells and spindle to stellate cells were present. Immunohistochemical stain showed that tumor cells expressed positivity for vimentin and partially positivity or negativity for cytokeratin. She was diagnosed as having undifferentiated sarcoma of the liver. She received seven courses of VAIA chemotherapy by CWS protocols. Chemotherapy was efficacious and the size of the tumor decreased considerably after the treatment. No tumor recurrence for 12 months is noted. (Korean J Hepatol 2007;13:96-102)
