¹Centre for Allogeneic Stem Cell Transplantation and Division of Clinical Immunology, Karolinska University Hospital Huddinge, Stockholm, Sweden

Correspondence: Professor O Ringdén, Division of Clinical Immunology, F79, Karolinska University Hospital Huddinge, Stockholm SE-141 86, Sweden. E-mail: Olle.Ringden@ki.se

Received 22 April 2008; Revised 19 June 2008; Accepted 23 June 2008; Published online 1 September 2008.

Abstract

The aim was to evaluate two transplant strategies for patients who lack HLA-identical donors, namely HLA-A, HLA-B or -DR1 mismatched unrelated donor (MM URD) transplants (n=14) and umbilical cord blood transplants (UCB, n=27). Diagnosis, disease stage and age were similar in the two groups. Cell dose was lower in the UCB group (P<0.001). Median time to ANC of >0.5 10⁹/l was 30 days in the UCB group and 17 days in the MM URD group (P=0.002). Engraftment of plt was delayed in the UCB group (P=0.03). The UCB patients required fewer erythrocyte transfusions (P=0.001). At 100 days, complete donor chimerism for CD3 was 63 and 44% in the UCB and MM URD groups, respectively. Acute GVHD of grades II–IV were 30% in the UCB group and 21% in the MM URD group. The corresponding figures for chronic GVHD were 9 and 20%, respectively. TRM was 30% in the UCB patients and 50% in the MM URD patients. Three-year survival was 66% in the UCB group and 14% in the MM URD group (P=0.006). Although the material is small and heterogeneous, engraftment was delayed, leukocyte chimerism was not significantly different and survival was superior using UCB rather than MM URD transplants.