Is there a role of high dose chemotherapy and autologous stem cell transplantation in the treatment of Ewing's sarcoma and osteosarcomas?

Although osteosarcomas are rare tumors, they are the most common primary bone tumors in children and adolescents younger than 20 years with a remarkable male predominance. Ewing's sarcoma (ES) is the second most common primary bone tumor in children and adolescents. The preferred actual treatment modality for osteosarcoma patients is neoadjuvant chemotherapy followed by complete surgical excision and adjuvant chemotherapy including agents such as doxorubicin, cisplatin, ifosfamide, and high-dose methotrexate which are widely used and accepted as being efficacious treatment strategies in osteosarcoma patients. Conventional treatments have increased overall survival (OS) rates in osteosarcoma and ES, but not as enough as desired. High dose chemotherapy (HDC) and autologous stem cell transplantation (ASCT) may be beneficial in some subgroup of ES, including children with partial response to conventional chemotherapy and with poor-risk as well as metastatic ES. HDC and ASCT remain as a clinical option in patients with ES, but it is considered as an experimental treatment approach for patients with osteosarcoma. In this review, we discussed the current approach and role of HDC and ASCT in the treatment of osteosarcoma and ES and focused on the current literature data evaluating the treatment outcomes of some sub-groups of high risk patients.