Background: Ewing sarcoma family of tumors is the second most common primary bone tumor of childhood. Extraosseous Ewing sarcoma family of tumors is rare. We present a pediatric case of primary endobronchial Ewing sarcoma family of tumors.
Case Report: A 12-year-old boy presented with dyspnea and chest radiography showed right pulmonary atelectasis. Chest computed tomography demonstrated tumor in the right main bronchus. Histopathological examination of the resected tumor demonstrated Ewing sarcoma family of tumors. No other lesions were detected throughout the body and the right main bronchus was thought to be the primary site. As of 1 year and 6 months after further resection of residual tumor followed by chemotherapy and radiotherapy, the patient remains disease-free.
Conclusions: Extraosseous Ewing sarcoma family of tumors arises in soft tissues of the trunk or extremities, but primary endobronchial Ewing sarcoma family of tumors has rarely been reported. Although quite rare, Ewing sarcoma family of tumors should be considered among the differential diagnoses for pediatric bronchial tumor.

Keywords: pediatric endobronchial tumor, atelectasis, Ewing sarcoma family of tumors