High dose therapy and autologous hematopoietic stem cell transplantation in poor risk solid tumors of childhood.

In the last two decades autologous hematopoietic stem cell transplantation (HSCT) has been increasingly used in the treatment of several poor risk solid tumors of childhood. Examples are recurrent or resistant cancers, metastatic presentation at diagnosis, incomplete surgical resection, unfavorable histologic and biological features. Results from the Children's Cancer Group randomized trial confirm the data from retrospective studies which reported the superiority of HSCT over standard chemotherapy for neuroblastoma. Several retrospective analyses support the use of HSCT in Ewing's sarcoma and in some brain tumors. No evidence of utility has been reported for rhabdomyosarcoma. The most widely utilized source of stem cells is peripheral blood, while there are conflicting data regarding the use of total body irradiation and purging of stem cells.