Allogeneic hematopoietic stem cell transplantation for chronic myeloid leukemia in Europe 2006: Transplant activity, long-term data and current results. An analysis by the Chronic Leukemia Working Party of the European Group for Blood and Marrow Transplantation (EBMT)

The introduction of imatinib mesylate has changed attitudes towards hematopoietic stem cell transplantation (HSCT) for chronic myeloid leukemia (CML). Information on the current use and results of HSCT is warranted. Data from 592 teams in 42 European countries described their use of HSCT for CML from 1990 to 2004. Outcomes were analyzed for 13,416 patients, with a median age of 36 years (range 1-71 years); 60% were male. The analysis considered three time cohorts, 1980 to 1990, 1991 to 1999 and 2000 to 2003. Survival, transplant-related mortality and relapse incidence were assessed at 20 years for the first cohort and compared at 2 years between the three cohorts. The numbers of HSCT for CML increased from 540 allogeneic HSCT in 1990 to 1,396 HSCT in 1999 and declined to 802 in 2004. One third of all patients and half of those with a low risk were alive at 20 years. Survival at 2 years has improved from 53% to 61% in the most recent years due to a reduction in transplant-related mortality from 41% to 30% in all patients and from 31% to 17% in low-risk patients. Stage, donor type, time interval, age and donor-recipient sex combination remain the main risk factors; patients with a risk score of 0 or 1 have a survival probability of 80% at 2 years. HSCT remains an important treatment option for patients with CML. The data describe the current status of this option and the outcome a patient can expect today. They provide an objective basis for decision making.