Intrathoracic extraskeletal Ewing's sarcoma: a case report and review of literature

Extraskeletal Ewing's sarcoma (EES) is a rare tumor of soft tissue. As an uncommon clinical entity with histologic features similar to those of other small round-cell tumors, EES occasionally produces difficulty in diagnosis. Hence, diagnosis should be confirmed by histochemical, immunohistochemical and clinical findings. Here, we describe a man aged 29 years who had intrathoracic mass was diagnosed as EES after incisional biopsy of the tumor. The presence of glycogen in the tumor cells was demonstrated by periodic acid-Schiff (PAS) stain but immunoreactivity for cytokeratin, epithelial membrane antigen, leukocyte common antigen, desmin, actin and neuron-specific enolase were absent; vimentin was present. The patient was successfully treated with VIP regimen (etoposide, ifosfamide and cisplatin) followed by local irradiation. He remained alive without recurrence after one year. A review of the literature and recent advances in the treatment of EES are reported.