Undifferentiated (embryonal) sarcoma of the liver was first defined as a separate clinicopathological entity in 1978. it is uncommon hepatic tumor of mesenchymal origin, usually observed in children and teenage, but also infrequently encounter in adult. It represent about 9-15% of all hepatic tumor in children. We report a case of undifferentiated embryonal sarcoma of the liver in a 6 year old girl who presented with non specific right hypochondrial pain and mass with fever. Laboratory studies of the liver function were normal and the other tests were non specific. Ultrasonography and CT scan showed a large heterogeneous mass ranging from cystic tissue with multiple septa to more predominant solid component in the right lobe of the liver. Exploratory laparotomy was performed and revealed a large mass in the right lobe and part of the left lobe of the liver. Tumor resection was performed and about 70% of the total liver was resected. Macroscopically, tumor was large solitary globular firm predominant solid mass weighing 1100gm and measuring 18 x 12 x 8 cm, with variegated cut surface of solid, cystic, necrotic and hemorrhagic areas. Microscopically, the tumor has a variable but distinctive sarcomatous appearance, composed of spindle, oval and stellate-shaped sarcomatous cells, with marked nuclear pleomorphism, closely packed in whorls or scattered loosely in a myxoid ground substance. Numerous bizarre multinucleated giant cells, containing large intracytoplasmic hyaline globules with ample mitosis many of which are atypical. Tumor cells entrapped hyperplastic bile ducts. Accordingly the diagnosis of
*Pathology Department, College of Medicine, University of Mosul.
**Pathology Lab, Al-Khansa'a Maternity Teaching Hospital, Mosul.
*** Department of Surgery, Nineveh College of Medicine, University of Mosul.
****Department of Pathology, College of Medicine, Baghdad University, Iraq.
undifferentiated embryonal sarcoma of the liver was performed. Conclusion: Prompt detection of this aggressive tumor with complete surgical resection is the key to a successful outcome. Prognosis recently improved following postoperative chemotherapy.