Unrelated versus related allogeneic stem cell transplantation after reduced intensity conditioning.
BACKGROUND
The use of reduced intensity conditioning (RIC) regimens in allogeneic hematopoietic stem cell transplantation (HSCT) has increased over the past five years.


METHODS
In this study, involving 137 patients, we compared the outcome after RIC in patients receiving grafts from matched unrelated donors (MUD; n=74) and sibling donors (n=63). The MUD and sibling groups were comparable regarding diagnosis, including solid tumors and hematological malignancies, and conditioning regimens.


RESULTS
Engraftment was successful in most patients (88%), with no significant difference between MUD and sibling transplants. Cytomegalovirus (CMV) infection was more common in the MUD group (65%) than in the sibling group (46%) (P=0.04). No difference in severe acute graft-versus-host disease (GVHD) was found between the groups. However, the incidence of chronic GVHD was higher after sibling transplants. This was probably due to higher donor age in this group, since this was the only significant risk factor for chronic GVHD in multivariate analysis. The incidence of transplant related mortality (TRM) was significantly higher after MUD transplantation (40%) than after sibling transplantation (16%) (P<0.01). Because relapse/disease progression was more common after sibling transplantation, there was no significant difference in overall survival between the two groups.


CONCLUSIONS
Using unrelated donors after RIC is feasible, but it resulted in more CMV infection and increased transplant-related mortality. Survival was comparable to that of sibling transplants.
Uzunel
Mehmet
M
Department of Clinical Immunology, Karolinska Institute at Karolinska University Hospital, Huddinge, Stockholm, Sweden. mehmet.uzunel@ki.se
Remberger
Mats
M
Sairafi
Darius
D
Hassan
Zuzana
Z
Mattsson
Jonas
J
Omazic
Brigitta
B
Barkholt
Lisbeth
L
Ringdén
Olle
O
D000208:Acute Disease; D000935:Antifungal Agents / Q000627:therapeutic use; D002423:Cause of Death; D002908:Chronic Disease; D016572:Cyclosporine / Q000627:therapeutic use; D003586:Cytomegalovirus Infections / Q000453:epidemiology; D006084:Graft Rejection / Q000453:epidemiology; D006086:Graft vs Host Disease / Q000453:epidemiology / Q000517:prevention & control*; D006801:Humans; D007166:Immunosuppressive Agents / Q000627:therapeutic use; D009181:Mycoses / Q000517:prevention & control; D035781:Siblings; D033581:Stem Cell Transplantation / Q000379:methods* / Q000401:mortality; D016019:Survival Analysis; D014019:Tissue Donors / Q000706:statistics & numerical data; D019172:Transplantation Conditioning / Q000379:methods*; D014184:Transplantation, Homologous; D017211:Treatment Failure; D016896:Treatment Outcome; D014740:Vidarabine / Q000031:analogs & derivatives / Q000627:therapeutic use
D000935:Antifungal Agents; D007166:Immunosuppressive Agents; D016572:Cyclosporine; D014740:Vidarabine; C024352:fludarabine