AIMS: To retrospectively study the DNA content in a series of childhood Ewing Family Tumors (EFT), and to investigate its prognostic value. METHODS: The study was performed on a series of 27 EFTs (osseous Ewing's sarcoma, 18 cases; extraosseous Ewing's sarcoma, 2; peripheral neuroepithelioma, 4; Askin Rosai tumors, 3