Extraskeletal Ewing's sarcoma: a preliminary review of 26 cases encountered in the Intergroup Rhabdomyosarcoma Study.

Twenty-six of three hundred and fourteen (26/314) patients whose tumors were reviewed by the Pathology Evaluation Committee of the Intergroup Rhabdomyosarcoma Study have histologic subtypes I and II which have morphologic characteristics similar to Ewing's sarcoma of bone. They are somewhat more common in an extremity lesion but have no relation to patient age. Disease-free survival is good; seventeen of twenty-six (17/26) or sixty-five (65%) percent thus far.