The tumours most frequently tested for molecular confirmation were Ewing sarcoma (ES) (761 patients), well/dedifferentiated liposarcoma (MDM2 status) (396 patients), synovial sarcoma (SS) (393 patients), myxoid/round cell liposarcoma (MLPS) (388 patients) and extraskeletal myxoid chondrosarcoma (EMC) (125 patients). The gene discussed is MDM2; the disease is synovial sarcoma.