High-dose chemotherapy and autologous peripheral blood stem-cell transfusion after conventional chemotherapy for patients with high-risk Ewing's tumors.

Although the overall results of treatment of Ewing's tumors have improved, patients with high-risk factors, including metastatic disease at diagnosis, bulky primary tumors, axial sites, and age >15 years, continue to have poor prognoses. The effects of high-dose chemotherapy and autologous peripheral blood stem-cell transplantation on high-risk Ewing's tumor patients have been reported. In most of these studies, conditioning and high-dose regimens varied among patients. Here we report the feasibility and effects of a high-dose chemotherapy regimen conducted in our institution. Seven patients with high-risk Ewing's tumors were treated by high-dose chemotherapy. The patients received four cycles of remission induction chemotherapy, and then peripheral blood stem cells were mobilized by high-dose etoposide and harvested. Myeloablative chemotherapy consisted of carboplatin, ifosfamide, and etoposide. The patients have 5-year overall and relapse-free survival probabilities of 0.86 and 0.81, respectively. The results were significantly better than those for patients treated with conventional chemotherapy alone. None of the patients had severe side effects. The high-dose regimen and transplantation were feasible and well tolerated. The poor prognoses of high-risk Ewing's tumor patients may be improved by high-dose chemotherapy with peripheral blood stem cell transplantation. However, the real impact of the therapy on the clinical outcome of patients with high-risk Ewing's tumors should be evaluated in a prospective, randomized study.