Imaging features of undifferentiated embryonal sarcoma of the liver: a series of 15 children.

Abstract

Undifferentiated embryonal sarcoma of the liver is a rare malignant mesenchymal tumour occurring mostly in children ages 6-10years. The discrepancy between its solid appearance on US and cystic-like appearance on CT has been described. To study the imaging particularities and similarities among our cases of undifferentiated embryonal sarcoma and to report the errors in initial diagnoses. We conducted a retrospective study of 15 children with undifferentiated embryonal sarcoma diagnosed or referred to our hospital during 1997-2015 and analysed the clinical, biological and imaging data. We identified eight boys and seven girls ages 9months to 14years. Ten children presented with abdominal pain. Alpha-fetoprotein was slightly increased in one. Initial US and CT had been performed for all, while additional MRI had been done in two children. Initial CT demonstrated a hypoattenuated mass in all. Rupture was seen in five and intratumoural bleeding in seven children. Tumour volumes reduced during neoadjuvant chemotherapy in 10 children. Undifferentiated embryonal sarcoma might be suggested in a non-secreting unifocal tumour with well-defined borders, fluid-filled spaces on US, hypoattenuation and serpiginous vessels on CT, and if there are signs of internal bleeding or rupture on CT or MRI.