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.

A Review of Allogeneic Hematopoietic Stem Cell Transplantation in Metastatic Breast Cancer.

Breast cancer (BC) has a high mortality rate and metastatic BC is almost incurable despite hormonal therapy and chemotherapy. The second and third lines of chemotherapies usually yield transient responses and the median survival is generally as low as 18-24 months. Autologous and allogeneic hematopoietic stem cell transplantation (HSCT) have been extensively investigated in this setting. The presence of immune mediated anti-tumor effects referred to as graft-versus-tumor (GvT) effects after allogeneic HSCT among patients with solid tumors have been clearly defined. The advantages of allogeneic HSCT over autologous HSCT for metastatic BC are i) cancer-free graft and ii) immune-mediated GvT effects mediated by human leukocyte antigen compatible donor T-cells. In conclusion, a GvT effect does exist against metastatic BC and play a key role in tumor response. This review aims to describe the background, rationale, and clinical results of allogeneic HSCT as a potential alternative treatment in metastatic BC.