Ifosfamide dose-intensification for patients with metastatic Ewing sarcoma.

Background: Outcomes for patients with metastatic Ewing sarcoma (ES) remain poor. We investigated whether the intensification of ifosfamide improved survival for patients with metastatic ES.

Procedure: We conducted a retrospective chart review of 30 patients with metastatic ES treated with the MSKCC "EFT regimen." The regimen included an intensification of ifosfamide dosing from 1,800 mg/m(2) /day × 5 days per cycle to 2,800 mg/m(2) /day × 5 days per cycle.

Results: Twenty six of the 30 patients completed planned chemotherapy. Two patients experienced disease progression during therapy. There were no toxic deaths. One patient developed secondary leukemia. The 4-year event free survival (EFS) was 27% and the overall survival (OS) was 39%.

Conclusions: Intensification of ifosfamide was tolerated and did not increase toxicity in patients with metastatic ES. The intensification did not improve outcomes for these patients with metastatic disease.