Undifferentiated Embryonal Sarcoma of the Liver (UESL) in Adolescents: An Unexpected Diagnosis.

Definitive diagnosis of pediatric liver masses can be challenging, because clinical manifestations are nonspecific, and ultimate diagnosis may be delayed. We describe 2 patients with liver masses that initially were misdiagnosed and treated as infectious hepatic lesions. Only after histologic examination the correct diagnosis of undifferentiated embryonal sarcoma of the liver was defined. Both patients underwent a complete tumor resection followed by chemotherapy with a favorable outcome.