Extraskeletal Ewing sarcoma of the diaphragm presenting with hemothorax.

Ewing sarcoma is a relatively uncommon malignant bone neoplasm that usually occurs in children and young adults and involves the major long bones, pelvis, and ribs. Primary diaphragmatic Ewing sarcoma is extremely rare. To the best of our knowledge, only three cases of primary Ewing sarcoma of the diaphragm have been reported. A 12-year-old girl presented spontaneous occurrences of the right hemothorax. After drainage, a roentgenogram film, computed tomography, ultrasonography, and magnetic resonance image showed a giant mass on the right diaphragm. Primary diaphragmatic tumor was resected totally by right posterolateral thoracotomy, and histologically, an extraskeletal Ewing sarcoma was identified. The patient received adjuvant radio-chemotherapy, and there was no evidence of disease 10 months after the operation. Although extremely rare, extraskeletal Ewing sarcoma should be kept in mind in the differential diagnosis of diaphragmatic soft tissue tumors.