Congenital Ewing sarcoma in retroperitoneum with multiple metastases.

A 7-day-old Japanese female showed the absence of spontaneous movement in her both legs. MRI revealed tumors in the retroperitoneum invading into the spinal canal, the left cerebral hemisphere and the right eyeball. Histological examination of retroperitoneal tumor revealed the sheets of undifferentiated small round cells with hyperchromatic nuclei and scanty cytoplasm. EWS-FLI1 fusion gene was detected by RT-PCR, indicating Ewing sarcoma. She received chemo-radiotherapy and survived for 2 years and 10 months despite the multiple metastases at initial presentation.