Primary Ewing's sarcoma family tumors of the lung a case report and review of the literature.

Ewing's sarcoma family tumors (ESFT) have been reported to originate in a variety of sites, most commonly in the extremities. We herein report a case of a primary ESFT of the lung presenting in an 8-year-old boy. A histological examination of hematoxylin-eosin stained sections showed a homogeneous population of closely packed small neoplastic cells. The tumor cells were strongly positive for CD99/MIC2 and negative for the leukocyte common antigen, myoglobin, desmin, epithelial membrane antigen, AE1/AE3 and synaptophysin. The patient was treated with neoadjuvant chemotherapy and surgery. Nine months later, he is in good condition and chest CT scans have revealed no evidence of either local recurrence or distant metastasis. Cases of ESFT of the lung have been reported in recent years but there are still few reports of primary ESFT of the lung. To date, only eight cases of ESFT of the lung have been reported in the literature. This is the first report of an ESFT of the lung occurring in a patient under 10 years of age. The clinical course and therapeutic management of ESFT are also discussed.