Undifferentiated Embryonal Sarcoma of the Liver in Adult Mimicking Hepatic Abscess.

Undifferentiated embryonal sarcoma is an uncommon malignant tumor of liver of mesenchymal cell origin, usually observed in children. We report a case in a 34 years old male who presented with right upper quadrant pain. Ultrasonography showed a complex solid cystic lesion. However, on computed tomography it appeared as predominantly cystic with small solid components within. It was initially diagnosed as hepatic abscess. After failure to improve on conservative treatment, the patient underwent surgical resection and histopathology revealed undifferentiated embryonal sarcoma. Here we describe the typical clinical and radiologic features of this rare tumor.