Ewing's Sarcoma

The purpose of this study is to look at the amount of function that returns in participants that have reconstruction with bone graft or artificial device and in participants who have tumor surgery plus regenerative osseous surgery. The study will look at the level of function for a period of 3 years after the surgery. Another purpose of this study is to look at how well the bone heals in participants undergoing regenerative surgery

The goal of this clinical trial is to to assess the efficacy of romiplostim as a supportive care measure in patients with a new diagnosis of Ewing sarcoma receiving interval-compressed chemotherapy. The main questions it aims to answer are: 1. To demonstrate the efficacy of romiplostim in patients with newly diagnosed Ewing sarcoma, measured specifically as the rate of CIT, defined as a failure to achieve platelet recovery (≥ 75,000/µL post nadir, without transfusion, or a platelet count sufficient to resume chemotherapy per provider and institutional standard) within 7 days of planned chemotherapy cycle start, measured during the continuation phase (cycle 7 to end of cycle 13 or 16, per AEWS0031/AEWS1221, or AEWS1031 respectively) of interval-compressed chemotherapy (every 2 week vincristine/cyclophosphamide +/- doxorubicin and ifosfamide/etoposide chemotherapy) as compared to published institutional historical control rate. 2. To determine the safety of incorporation of romiplostim supportive care when given concurrently with Ewing sarcoma therapy. 3. To determine the feasibility of incorporation of romiplostim supportive care into upfront Ewing sarcoma regimens.

This study is a randomized, controlled, multicenter, prospective clinical trial with a planned enrollment of 74 patients, who will be randomly assigned in a 2:1 ratio. After enrollment, patients will receive either irinotecan liposomal injection combined with temozolomide and vincristine or irinotecan injection combined with temozolomide and vincristine. The aim is to evaluate the efficacy, safety, and impact on quality of life of the irinotecan liposomal combination regimen compared to the irinotecan injection combined with temozolomide and vincristine in the treatment of advanced Ewing's sarcoma.