Unrelated donor marrow transplantation initial experience of the italian bone marrow transplant group (GITMO)

From 1 September 1988 to 30 September 1993, a search for an unrelated donor (URD) was started for 633 Italian patients. Eighty-five of them (13%) were transplanted. Despite the introduction of more strict criteria for the selection of compatible donors, the percentage of patients who reached transplant increased significantly after December 1992. For patients who started a search before and after January 1993, respectively the probability of transplant by 8 and 16 months from search activation was 4 and 10%, compared to 22 and 37% (P = 0.0001). The average intervals between search activation and graft were 15 and 8 months respectively, for the first and second group (P = 0.0001). Data of 75 consecutive transplants performed up to March 1994 were analyzed. Actuarial 2-year survival was 15% for patients grafted before 1992 and 40% for those grafted after January 1992. In this latter period, survival of patients with malignant and non-malignant disorders was 32 and 67%, respectively. In univariate analysis, patients younger than 16 years (P = 0.01), patients grafted after 1992 (P = 0.01) and patients receiving the marrow from a 6-antigen matched donor (P = 0.01) showed a higher survival probability. Multivariate analysis did not show any difference, probably due to the low number of patients and to short follow-up. The adoption of stricter and more accurate HLA-matching criteria and the consequent reduction of deaths related to acute GVHD were the main reasons for the improvement of survival observed in patients grafted after 1992.