High-Dose Continuous Infusion Ifosfamide as Effective Palliation in a Patient With Relapsed Ewing Sarcoma With Bone Marrow Infiltration and Severe Thrombocytopenia: A Case Report

Background: Ewing sarcoma is a rare primary mesenchymal tumor of the bone that requires an intensive multimodal therapeutic approach. Multidrug chemotherapy regimens are also the backbone for relapsing/recurring Ewing sarcoma treatment, yet when the disease relapses as bone marrow infiltration, combination chemotherapy might be difficult to administer and prognosis is poor. Case: This report describes the case of a 22-year-old patient with Ewing sarcoma who developed severe pancytopenia due to bone marrow infiltration, and who was treated with high-dose continuous infusion ifosfamide, obtaining both clinical, radiological, and hematological response lasting for about 7 months. Conclusion: To our knowledge, this is the first described case of a patient with bone marrow infiltration from Ewing sarcoma presenting with severe thrombocytopenia successfully managed with low-dose continuous infusion ifosfamide, providing almost 7 months of progression-free survival. Considering the very dismal prognosis of Ewing sarcoma relapsing with bone marrow infiltration, this case might be of help when decision-making is required in this setting.