The hope and the reality of reduced intensity transplants in children with malignant diseases.
Reduced intensity preparative regimens are increasingly used for conditioning prior to allogeneic stem cell transplantation. As opposed to classical methods of pre-transplant conditioning, patients receive predominantly immunosuppressive therapies that facilitate early engraftment, while cells within the graft itself promote continuation of the engraftment process. Despite early hopes that this form of transplant would be devoid of grade III and IV acute toxicities, there is a substantial amount of short-term morbidity associated with the technique. Although long-term follow-up is not yet available, it is hoped that these regimens will spare young patients many of the late effects (cataracts, growth retardation, endocrine and reproductive problems) that are often associated with classical pre-transplant conditioning regimens. Reliable engraftment and leukemic control have been demonstrated in a large number of both adult and pediatric transplant recipients of these regimens, many of whom were deemed at high risk for standard conditioning because of serious co-morbidities, previous autologous transplantation or multiply relapsed disease. A brief review of the state of the art of this technology as it applies to pediatric transplantation is presented. Preliminary results of a survey of pediatric transplant centers indicate that a variety of protocols are used for a variety of indications. The use of standardized criteria for implementation of reduced intensity preparative regimens, the use of a limited number of regimens, and more extensive data collection will permit the elaboration of prospective comparative studies of this new and exciting modality.
Stein
J
J
Department of Pediatric Hematology Oncology, Schneider Children's Medical Center of Israel, Petah Tiqva, and Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel.
Dini
G
G
Yaniv
I
I
D000328:Adult; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D008297:Male; D009369:Neoplasms / Q000401:mortality / Q000628:therapy*; D033581:Stem Cell Transplantation / Q000379:methods / Q000401:mortality / Q000592:standards*; D019172:Transplantation Conditioning / Q000379:methods / Q000401:mortality / Q000592:standards*; D014184:Transplantation, Homologous