Effect of graft source on unrelated donor haemopoietic stem-cell transplantation in adults with acute leukaemia: a retrospective analysis.
BACKGROUND
Umbilical-cord blood (UCB) is increasingly considered as an alternative to peripheral blood progenitor cells (PBPCs) or bone marrow, especially when an HLA-matched adult unrelated donor is not available. We aimed to determine the optimal role of UCB grafts in transplantation for adults with acute leukaemia, and to establish whether current graft-selection practices are appropriate.


METHODS
We used Cox regression to retrospectively compare leukaemia-free survival and other outcomes for UCB, PBPC, and bone marrow transplantation in patients aged 16 years or over who underwent a transplant for acute leukaemia. Data were available on 1525 patients transplanted between 2002 and 2006. 165 received UCB, 888 received PBPCs, and 472 received bone marrow. UCB units were matched at HLA-A and HLA-B at antigen level, and HLA-DRB1 at allele level (n=10), or mismatched at one (n=40) or two (n=115) antigens. PBPCs and bone-marrow grafts from unrelated adult donors were matched for allele-level HLA-A, HLA-B, HLA-C, and HLA-DRB1 (n=632 and n=332, respectively), or mismatched at one locus (n=256 and n=140, respectively).


RESULTS
Leukaemia-free survival in patients after UCB transplantation was comparable with that after 8/8 and 7/8 allele-matched PBPC or bone-marrow transplantation. However, transplant-related mortality was higher after UCB transplantation than after 8/8 allele-matched PBPC recipients (HR 1.62, 95% CI 1.18-2.23; p=0.003) or bone-marrow transplantation (HR 1.69, 95% CI 1.19-2.39; p=0.003). Grades 2-4 acute and chronic graft-versus-host disease (GvHD) were lower in UCB recipients compared with allele-matched PBPC (HR 0.57, 95% 0.42-0.77; p=0.002 and HR 0.38, 0.27-0.53; p=0.003, respectively), while the incidence of chronic, but not acute GvHD, was lower after UCB than after 8/8 allele-matched bone-marrow transplantation (HR 0.63, 0.44-0.90; p=0.01).


CONCLUSIONS
These data support the use of UCB for adults with acute leukaemia when there is no HLA-matched unrelated adult donor available, and when a transplant is needed urgently.
Eapen
Mary
M
Center for International Blood and Marrow Transplant Research, Medical College of Wisconsin, MW, USA.
Rocha
Vanderson
V
Sanz
Guillermo
G
Scaradavou
Andromachi
A
Zhang
Mei-Jie
MJ
Arcese
William
W
Sirvent
Anne
A
Champlin
Richard E
RE
Chao
Nelson
N
Gee
Adrian P
AP
Isola
Luis
L
Laughlin
Mary J
MJ
Marks
David I
DI
Nabhan
Samir
S
Ruggeri
Annalisa
A
Soiffer
Robert
R
Horowitz
Mary M
MM
Gluckman
Eliane
E
Wagner
John E
JE
D000293:Adolescent; D000328:Adult; D016026:Bone Marrow Transplantation / Q000009:adverse effects; D036101:Cord Blood Stem Cell Transplantation / Q000009:adverse effects; D018572:Disease-Free Survival; D005260:Female; D006086:Graft vs Host Disease / Q000517:prevention & control; D018380:Hematopoietic Stem Cell Transplantation / Q000009:adverse effects / Q000379:methods; D006801:Humans; D015470:Leukemia, Myeloid, Acute / Q000628:therapy*; D008297:Male; D008875:Middle Aged; D036102:Peripheral Blood Stem Cell Transplantation / Q000009:adverse effects; D054198:Precursor Cell Lymphoblastic Leukemia-Lymphoma / Q000628:therapy*; D016016:Proportional Hazards Models; D012189:Retrospective Studies; D014184:Transplantation, Homologous