Cutaneous and subcutaneous Ewing sarcoma carries a more favourable prognosis than other soft-tissue locations. When initial multimodal therapy does not achieve the required histological and radiological endpoints, a structured second-line approach is indicated.
This protocol addresses patients with cutaneous or subcutaneous Ewing sarcoma who have relapsed or failed to achieve an adequate response after first-line multimodal treatment. Retrospective data support a better prognosis for this tumour location relative to other localised soft-tissue Ewing sarcoma; the number of initial chemotherapy cycles is typically determined case by case at a multidisciplinary level given this favourable baseline.
The prior treatment line employed a multimodal approach with interval-compressed chemotherapy incorporating vincristine, doxorubicin, cyclophosphamide, ifosfamide, and etoposide (VDC/IE regimen), combined with local therapy — surgical excision or radiotherapy.
Escalation to this protocol is triggered when the previous line did not achieve: complete histological tumour response (100% necrosis, fibrosis, and calcification on surgical specimen assessment), or an adequate reduction in soft-tissue mass size on MRI.