Double umbilical cord blood transplantation for hematological malignancies: a long- term analysis from the SFGM-TC registry.

International audience: Allogeneic hematopoietic stem cell transplantation (HSCT) is a curative treatment for many hematological malignancies for which umbilical cord blood (UCB) represents an alternative source of HSC. In order to overcome the low cellularity of one UCB unit, double UCBT (dUCBT) has been developed in adults. We have analyzed the outcome of 136 patients who underwent dUCBT reported to the SFGM-TC registry between 2005 and 2007. Forty-six patients received myeloablative and 90 reduced intensity conditioning regimens. There were 84 leukemias, 17 NHL, 11 myelomas and 24 other hematological malignancies. At transplantation, 40 (29%) patients were in CR1. At day 60 after transplantation, the cumulative incidence of neutrophil recovery was 91%. We observed one UCB unit domination in 88% of cases. The cumulative incidence of day 100 aGVHD, cGVHD, TRM and relapse at 2 years were 36%, 23%, 27% and 28% respectively. After a median follow-up of 49.5 months, the 3 years probabilities of overall and progression-free survival were 41% and 35% respectively with a significant OS advantage when male cord engrafted male recipients. We obtained a long term plateau among patients in CR1 which makes dUCBT a promising treatment strategy for these patients