Irinotecan plus temozolomide in relapsed Ewing sarcoma: an integrated analysis of retrospective studies

Abstract Background The prognosis of patients with relapsed Ewing sarcoma is poor. In this study, we aimed to pooled-analyze the efficacy and safety of the combination of irinotecan and temozolomide in treating patients with relapsed Ewing sarcoma. Methods PubMed, Cochrane CENTRAL, Web of Science, and EMBASE were systematically searched on September 27, 2021. The primary outcomes were rates of objective response and disease control, and the secondary outcomes were toxicities. Results Six retrospective studies with 184 patients were enrolled in the analysis. The median age ranged from 14 to 21. The integrated rates were 44% (95% confidence interval [CI] 31–58) for objective response and 66% (55–77) for disease control. Grade 3–4 neutropenia, thrombocytopenia, and diarrhea occurred in 8% (3–16), 7% (3–11), and 8% (5–10) of chemotherapeutic cycles, respectively. 18% (7–32) and 6% (2–11) of patients suffered grade 3–4 neutropenia and thrombocytopenia after irinotecan plus temozolomide treatment. Conclusion Irinotecan plus temozolomide combination chemotherapy showed antitumor activity and an acceptable safety profile in patients with relapsed Ewing sarcoma. More future prospective studies are needed to confirm the retrospective results.