title: Haploidentical stem cell transplantation for children with high-risk leukemia.
abstract: BACKGROUND
  The Chilean population is ethnically diverse, and more than 50% of children referred for hematopoietic stem cell transplantation (HSCT) lack a suitable donor.
  
  
  METHODS
  To expand the donor pool, we assessed the feasibility, tolerance, and efficacy of using a haploidentical (HI) donor and a reduced-intensity conditioning regimen for high-risk pediatric leukemia. This study was facilitated by technology transfer from St. Jude Children's Research Hospital over the 2 preceding years.
  
  
  RESULTS
  Between March 2006 and April 2009, 10 patients (median age, 9.8 years) received T cell-depleted grafts at Calvo Mackenna Hospital in Santiago. Median cell doses were CD34+: 7.45 × 10(6)/kg (range, 4.00-20.20 × 10(6)/kg); CD3+: 0.88 × 10(5)/kg (0.11-1.35 × 10(5)/kg); and CD56+: 71.30 × 10(6)/kg (31.50-131.80 × 10(6)/kg). Nine patients experienced complete engraftment; six of the nine remain alive and clinically well 13-50 months post-HSCT. Three patients died after bone marrow relapse, while only one died of transplant-related causes. Virus reactivation was the main post-transplant complication: 5/10 had positive CMV PCR but none had CMV disease. One patient developed acute GvHD > grade II and only one had chronic GvHD.
  
  
  CONCLUSIONS
  HI-HSCT is feasible in our setting, offers a rational treatment option, and expands the donor pool significantly for children with high-risk leukemia in a developing country. This information is especially relevant to other ethnically diverse populations that are poorly represented in international donor registries.
authors.affiliation: Bone Marrow Transplant Unit, Hospital Dr. Luis Calvo Mackenna, Santiago, Chile. jpalmab@vtr.net
authors.forename: Julia
authors.initials: J
authors.lastname: Palma
authors.forename: Lucia
authors.initials: L
authors.lastname: Salas
authors.forename: Flavio
authors.initials: F
authors.lastname: Carrión
authors.forename: Cristián
authors.initials: C
authors.lastname: Sotomayor
authors.forename: Paula
authors.initials: P
authors.lastname: Catalán
authors.forename: Claudia
authors.initials: C
authors.lastname: Paris
authors.forename: Victoria
authors.initials: V
authors.lastname: Turner
authors.forename: Hugo
authors.initials: H
authors.lastname: Jorquera
authors.forename: Rupert
authors.initials: R
authors.lastname: Handgretinger
authors.forename: Gastón K
authors.initials: GK
authors.lastname: Rivera
mesh_terms: D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D002677:Chile; D003586:Cytomegalovirus Infections / Q000209:etiology / Q000401:mortality / Q000628:therapy; D005260:Female; D006085:Graft Survival; D006086:Graft vs Host Disease / Q000209:etiology / Q000401:mortality / Q000628:therapy; D006801:Humans; D007938:Leukemia / Q000401:mortality / Q000628:therapy*; D019520:Living Donors; D008297:Male; D012042:Registries; D012307:Risk Factors; D033581:Stem Cell Transplantation; D014184:Transplantation, Homologous