Text Box: UNDIFFERENTIATED EMBRYONAL SARCOMA (UES) OF THE LIVER: CT FINDINGS (ANALYSIS OF 6 CASES) PENG Yun , XU Saying , ZHU Xiudan Department of Radiology, Beijing Children’s Hospital, Capital University of Medical Sciences, Beijing, China Objective: To improve the recognition of CT various appearances of hepatoblastoma (HB) and evaluate the role of CT scan in diagnosis. Method: In all 24 cases abdominal scan was performed, in 12 of them contrast CT enhanced was available. The CT manifestions of 24 HB cases were analyzed correlated with clinical-pathological findings. Results: Fourteen tumors involved right lobe, 4 left lobe, 6 both liver lobes, only one invading the liver diffusely. Most of HB appeared as an intrahepatic well-circumscribed spheric or lobulated solid mass with or without pseudocapsule. Three of them manifested as multiple nodularity and distributed in one or both liver lobes. Exophytic growing of tumor was seen in 7 cases. The tumor mass was usually with inhomogeneous density and heterogeneous enhancement, some associated with reticular and curve-line density. Peripheral rim enhancement only presented in 3 cases. Calcified foci were found in 6 cases. Hepatic parenchyma outside the tumor was normal in all cases. Two subdiaphragmatic and greater omentum tumor infiltrations could not be found on CT scans. Rare findings included tumor thrombus is one case of IVC, lymphnodal metastasis in one case. Conclusion: The various CT configurations and patterns described in this study are helpful in recognizing and evaluating the prognosis of HB. CT scan could accurately localize and characterize the mass, while not always correct in tumor staging. Undifferentiated embryonal sarcoma of the liver: CT findings (analysis of 6 cases) PENG Yun , XU Saiying, ZHU Xiudan Radiology/Imaging Radiological Department, Beijing Children’s Hospital, Nan Lishi Road 56#, Beijing Beijing CHINA 100045 68028401-2663 Pm: 8:00-20:00 PENG Yun 1211