Expanded Access Through Cancer Trials Support Unit to Children's Oncology Group Sarcoma Trial AEWS1031 for Adolescents and Young Adults.

Ewing sarcoma family of tumors (ESFT) is the second most common malignant tumor of bone and occurs predominantly in the adolescent and young adult age group.1 They include Ewing sarcoma, atypical Ewing sarcoma, and peripheral primitive neuroectodermal tumor of bone. Even though this malignancy arises mainly from the bone, primary extraosseous tumors also occur. These tumors are believed to be of neural crest origin and occur with almost equal incidence in the extremities and central axial sites. There is a dramatic racial variation in incidence, with almost no discernable incidence in individuals of African and Asian or Pacific island descent. Other than race, there are no known risk factors for ESFT. A EWS-ETS fusion protein is characteristic of ESFT, with over 85% of tumors expressing the EWS-FLI-1 fusion transcript.2