A pilot study of low-dose anti-angiogenic chemotherapy in combination with standard multiagent chemotherapy for patients with newly diagnosed metastatic Ewing sarcoma family of tumors: A Children's Oncology Group (COG) Phase II study NCT00061893.

Background: The aims of this study were to determine the feasibility of the combination of low dose, anti-angiogenic chemotherapy with standard therapy for patients with metastatic Ewing sarcoma (ES), and to obtain preliminary outcome data.

Procedures: Patients with metastatic ES were eligible. Therapy consisted of alternating cycles of ifosfamide-etoposide, and vincristine, doxorubicin, cyclophosphamide. Vinblastine and celecoxib were concomitantly administered. Surgical, radiotherapeutic, or combination local control therapy was given per institutional preference.

Results: Thirty-five eligible patients were enrolled. Ninety percent received at least 75% of planned vinblastine/celecoxib doses. There was no excess of neurologic, infectious, hemorrhagic, or cardiovascular toxicities. However, 7 of 21 patients who received pulmonary irradiation prior to experiencing pulmonary toxicity did develop grade 2 or greater pulmonary toxicity, including two deaths of apparent radiation pneumonitis. Fourteen of 16 patients with pelvic disease received local irradiation. Hemorrhagic cystitis developed in six patients, five of whom had received pelvic irradiation. The overall 24-month event free survival was 35% (19-51%); 71% (26-92%) for the seven with isolated pulmonary metastases, 26% (10-45%) for all others.

Conclusion: The combination of vinblastine/celecoxib metronomic therapy with standard ES treatment was feasible according to the protocol definitions. However, excess toxicity in irradiated areas was noted and limits the usefulness of this protocol. The 24-month EFS for those with isolated pulmonary metastases is better than historical controls, although the number of patient number is small, follow up short and we are lacking contemporaneous controls.