Allo-SCT in children with high-risk leukemia using unmanipulated grafts from alternative donors

Allogeneic HSCT is a curative treatment for high-risk leukemia. In Europe, approximately 15% of children have an HLA-matched sibling, but in 65-70% HLA allele-matched (9-10/10) unrelated donors (UD) can be identified. Transplantation using an HLA partially mismatched donor, unrelated cord blood or haploidentical family donor with graft manipulation is then considered with preference on the basis of local experience and/or availability. Here we evaluate the outcomes of 87 consecutive patients with leukemia transplanted with unmanipulated graft from matched or partially mismatched UD or cord blood (CB) at our institution between January 2001 and December 2007. Within the median follow-up of 30 months, the acute GVHD grade II was diagnosed in 70.9% patients; grades III-IV only in 4.6%. The overall incidence of chronic GVHD was 43.3% (extensive in 34.9%). The probability of 3-year EFS was 59.5% and that of 3-year overall survival was 66.9%. TRM at day +100 was 4.5%, and overall it was 13.8%. Fourteen patients (16.1%) died as a consequence of post-transplant leukemia relapse. We conclude that the prognosis of patients transplanted for leukemia using unmanipulated grafts from HLA-matched or partially mismatched UD or CB is comparable and satisfactory. TRM and relapse rate are lower than in the earlier period.