Autologous stem cell transplantation for high-risk Ewing's sarcoma and other pediatric solid tumors

The prognosis for many pediatric and young adult patients with solid tumors that have metastasized at the time of diagnosis or have relapsed after therapy remains very poor. The steep dose-response curve of many of these tumors to alkylating agents makes myeloablative chemotherapy followed by autologous stem cell transplantation (ASCT) an attractive potential therapy. The role of ASCT for these high-risk patients is yet to be conclusively determined. We have transplanted 36 patients on two consecutive protocols with a variety of histological diagnoses. Overall survival (OS) was 63% (95% CI: 47-79%) at 1 year and 33% (95% CI: 16-50%) at 3 years. Patients with a diagnosis of Ewing's sarcoma (ES) or desmoplastic small round cell tumor (DSRCT) had significantly better survival than those with other diagnoses with estimated 3-year OS of 54% (95% CI: 29-79%) for this group of patients (P = 0.03). There were two transplant-related deaths both attributable to hepatic veno-occlusive disease. Median follow-up among survivors is 3.5 years (range: 0.6-7.9 years). These data justify continued investigation of ASCT as a consolidation therapy in patients with metastatic or relapsed ES and DSRCT.