Clinical Experience With RIST-Based Multimodality Therapy in Relapsed Ewing Sarcoma: A Descriptive Single-center Case Series.

BACKGROUND

Outcomes for relapsed Ewing sarcoma remain poor. The RIST regimen (rapamycin, irinotecan, dasatinib, temozolomide) provides a targeted biological alternative to standard salvage chemotherapy.

METHODS

We report 3 patients treated with RIST for relapsed Ewing sarcoma.

Results

One patient with measurable disease achieved an early partial response before progressing at 9 months. Two patients received RIST as post-local-therapy consolidation with no evidence of disease, maintaining disease control for 41 and 44 months. Toxicities were manageable and primarily hematologic, without treatment discontinuations.

CONCLUSION

Prolonged outpatient RIST administration is feasible, and its role as multimodality consolidation warrants further prospective evaluation.