Ewing's sarcoma characterized by the t(11; 22) (q24; q12) translocation at several but prioritized breakpoint sites, resulting in the EWS/FLI1 fusion gene is the second most frequently diagnosed primary malignant bone tumor in the US with an annual incidence, from birth to age 20, of 2.9 cases per million population. The survival rate for patients with high-risk recurrent disease (relapse < 2 years) is < 10% at 5 years. Moreover, of patients who progress after second line treatment, eighty percent do not achieve a second complete response and of these patients < 10% survive one year. Refractory patients to both frontline and second line therapy have even worse prognosis.