Undifferentiated embryonal sarcoma of liver: Paradoxical imaging appearance

Undifferentiated embryonal sarcoma of the liver is a rare entity. It is a malignant primitive mesenchymal tumor seen in the pediatric age group often between 6 to 10 years of age. It involves the right lobe of the liver commonly and is usually asymptomatic. Acute presentation in these cases is secondary to its rupture/ wall dehiscence. Alfa fetoprotein, a tumor marker elevated in most of the hepatic malignant tumors is however normal in undifferentiated embryonal sarcoma. Imaging wise it is a large encapsulated multiseptated lesion. It shows a "paradoxical appearance" with a predominantly solid appearance on ultrasonography and cystic appearance on CT/MRI. This is a peculiar feature that can help in the early diagnosis of this entity. Besides, normal serum alfa fetoprotein levels favor its diagnosis. Hereby we present a case of a 5-year-old female child, presented with complaints of acute onset abdominal pain and distension which on imaging investigation showed a liver mass with typical paradoxical appearance on ultrasonography, CT and MRI as described.