High-dose therapy and autologous hematopoietic cel transplantation rescue in children with neuroblastoma and Ewing sarcoma

Background. High-dose therapy (HDT) with autologous stem cell rescue has been recently applied in very-poor-risk pediatric solid tumors. Promising data have become available with the use of high-dose busulfan in neuroblastoma (NBL) and Ewing sarcoma (ES), and with high-dose treosulfan in ES. HDT approach resulted in an encouraging outcome without toxic mortality for high-risk patients. Objective. The objective of this study is to present transplant outcomes, that is disease-free-survival and overall survival in children with high-risk NBL and ES undergoing auto-HSCT. Patients and methods. A total number of 47 NBL and 20 ES auto-HSCT performed between 2004 and 2016 in a single transplant center were included in this analysis. Results. Probability of 3-years pOS was 0.79±0.06 and 0.46±0.14 for NBL and ES patients, respectively. Relapse incidence at 3 years after HSCT was 0.37±0.08 and 0.26±0.11 for NBL and ES patients, respectively. The number of relapses at 3 years after HSCT was 15/47 in NBL and 6/20 in ES. Busulfan-based vs treosulfan-based conditioning in ES patients resulted in lower relapse and death rates. NBL and ES patients transplanted in complete remission (CR1) had lower relapse rates and lower death rates than patients at CR>1. Conclusion. Obtained results of auto-HSCT confirm the therapeutic benefit for children with NBL and ES. Recent reports on current practice of HSCT in Europe indicate HDT with auto-HSCT as a standard of care in pediatric patients with high risk or relapsed NBL and ES.