Primitive neuroectodermal tumor of the liver: a case report of a rare case in pediatrics.

Primitive neuroectodermal tumors (PNETs) belong to the Ewing sarcoma family of tumors. These lesions are highly aggressive and are usually found in paravertebral regions, lower limbs, and thorax. However, abdominal PNETs are extremely rare, and only 3 cases of pediatric PNET of the liver have been previously reported. Most patients exhibit symptoms associated with mass effect, due to rapid tumor growth and dissemination. Therefore, an appropriate differential diagnosis is of pivotal importance in order to initiate the corresponding treatment. Here we report the case of a 4-year-old female patient who was diagnosed with PNET of the liver, and we discuss the analysis of focal liver lesions and differential diagnosis in pediatric patients.