Rapid and complete donor chimerism in adult recipients of unrelated donor umbilical cord blood transplantation after reduced-intensity conditioning.
Reduced-intensity conditioning may reduce transplantation-related mortality in high-risk adults undergoing hematopoietic transplantation. We investigated unrelated donor umbilical cord blood (UCB) transplantation after such conditioning in 43 patients (median age, 49.5 years; range, 22-65 years) with a primary end point of donor engraftment. The first 21 patients received busulfan 8 mg/kg, fludarabine 200 mg/m2, and 200 cGy of total body irradiation (Bu/Flu/TBI). Subsequent patients (n = 22) received cyclophosphamide 50 mg/kg, fludarabine 200 mg/m2, and 200 cGy TBI (Cy/Flu/TBI). UCB grafts (93%) were 1-2 HLA antigen-mismatched with the recipient and contained a median cryopreserved cell dose of 3.7 x 107 (range, 1.6 x 107-6.0 x 107) nucleated cells per kilogram of recipient body weight (NC/kg). Graft versus host disease (GVHD) prophylaxis was cyclosporin A to day 180 plus mycophenolate mofetil to day 30. The cumulative incidence of sustained donor engraftment was 76% (95% confidence interval [CI], 56%-96%) for Bu/Flu/TBI recipients and 94% (95% CI, 84%-100%) for Cy/Flu/TBI recipients. The median day of neutrophil recovery (at least 0.5 x 109/L) for engrafting Bu/Flu/TBI recipients was 26 days (range, 12-30 days) and for Cy/Flu/TBI recipients was 9.5 days (range, 5-28 days). Incidence of grades III-IV acute GVHD was 9% (95% CI, 1%-17%), and survival at 1 year was 39% (95% CI, 23%-56%). These data demonstrate that 0-2 antigen mismatched UCB is sufficient to engraft most adults after reduced-intensity conditioning and is associated with a low incidence of severe acute GVHD.
Divisions of Medical and Pediatric Hematology, Oncology and Transplantation, University of Minnesota Blood and Marrow Transplant Program, Minneapolis, MN, USA. barke014@tc.umn.edu
Juliet N
JN
Barker
Daniel J
DJ
Weisdorf
Todd E
TE
DeFor
Bruce R
BR
Blazar
Jeffrey S
JS
Miller
John E
JE
Wagner
D000328:Adult; D000368:Aged; D002066:Busulfan / Q000008:administration & dosage; D036101:Cord Blood Stem Cell Transplantation; D005312:Fetal Blood; D006085:Graft Survival; D006086:Graft vs Host Disease / Q000188:drug therapy / Q000235:genetics* / Q000401:mortality*; D006801:Humans; D007166:Immunosuppressive Agents / Q000008:administration & dosage; D015994:Incidence; D008875:Middle Aged; D012008:Recurrence; D012307:Risk Factors; D015996:Survival Rate; D018183:Transplantation Chimera; D019172:Transplantation Conditioning; D014740:Vidarabine / Q000008:administration & dosage / Q000031:analogs & derivatives*
D007166:Immunosuppressive Agents; D014740:Vidarabine; D002066:Busulfan; C024352:fludarabine