Comparative Analysis of Outcomes of Allogeneic Peripheral Blood Stem Cell Transplantation From Related and Unrelated Donors.

Abstract 3381

Poster Board III-269

This study compared the results of allogeneic peripheral blood stem cell transplantation (PBSCT) from unrelated and related donors, and involved 235 consecutive patients from 10 centers who received an allogeneic PBSCT for hematological malignancies between Jan 2004 and Dec 2008. Among these patients, 160 (68.1%) received an HLA-matched related PBSCT and 75 (31.9%) a matched unrelated PBSCT. Sixty-five patients (27.7%) had a high-risk disease status at transplantation. The cumulative incidence of acute graft-versus-host disease (GVHD) was 43.9% for the related PBSCT group and 59.3% for the unrelated PBSCT group (P-value:0.011). Although the cumulative incidence of chronic GVHD was no different between the related (54.2%) and unrelated (64.9%; P-value:0.199) PBSCT groups, the cumulative incidence of extensive chronic GVHD was higher among the unrelated PBSCT group (34.9%) than among the related PBSCT group (17.0%; P-value:0.015). Plus, the unrelated PBSCT group showed a higher cumulative incidence of CMV infection (44.6%) than the related PBSCT group (26.8%; P-value:0.002). The overall survival rate at four-year was 58.2% versus 49.1% (p=0.698) and the cumulative incidence of relapse 28.4% versus 25.0% (P-value:0.289) for the related and unrelated PBSCT groups, respectively. Among the factors examined, unrelated PBSCT (P-value:0.024), the CD34-positive cell count (>6 × 10⁶/kg; P-value:0.041), and CMV infection (P-value:0.066) were all related with a higher incidence of extensive chronic GVHD. However, in a multivariate analysis, only unrelated PBSCT was identified as a risk factor for the development of extensive chronic GVHD (hazard ratio=2.012, 95% confidence interval=1.006-4.023; P-value:0.048). In conclusion, the overall survival and relapse incidence were not significantly different between the related and unrelated PBSCT groups. However, a higher incidence of CMV infection and extensive chronic GVHD was observed in the unrelated PBSCT group.