Undifferentiated embryonal sarcoma of the liver in an adult patient

Undifferentiated embryonal sarcoma of the liver (UESL) is rare primary hepatic sarcoma and is known to occur in pediatric patients. This case is the UESL occurred in a 51-year old male patient. Multilocular cystic lesion was composed of primitive spindle cells without specific differentiation. This rare case would help to review differential diagnosis of primary sarcoma in liver and cystic neoplasm of the liver.

Primary Sarcomas of the Liver

Primary hepatic sarcomas are uncommon, representing less than 1% of the primary malignant lesions of the liver. Three patients underwent resection for primary hepatic sarcoma at the Department of Surgery, Inje University Paik Hospital, Seoul: a 6 year-old girl with malignant mesenchmoma, a 74 year-old man with malignant fibrous histiocytoma and a 53 year-old man with rhabdomyosarcoma. Abdominal mass, fever with chills, and abdominal pain were the presenting symptoms, respectively. The patient with rhabdomyosarcoma was positive for HBsAg and had chronic active hepatitis. AFP level was elevated in this patient. CA 19-9 level was elevated in the patient with malignant fibrous histiocytoma. CEA levels were normal in all cases. All these tumors were hypodense on computed tomography. Malignant mesenchymoma was hypovascular and rhabdomyosarcoma was hypervascular on angiography. Immunohistochemical stains of the tumors were positive for vimentin but negative for epithelial markers, differentiating these lesions from other hepatic tumors. Electron microscopic examination was helpful in the diagnosis of the specific type of primary hepatic sarcoma. None had postoperative adjuvant chemotherapy or radiotherapy. The patient with malignant mesenchymoma, who underwent right hepatic trisegmentectomy, was disease free at 32 months. The patient with malignant fibrous histiocytoma, who underwent non-curative excision, died of the tumor at 2 months. The patient with rhabdomyosarcoma, who underwent posterior segmentectomy, was alive at 4 months. Resection of primary hepatic sarcoma should be executed if feasible, with potential survival measured in years, in view of the lack of other effective treatment modalities.