Risk factors for therapy-related myelodysplastic syndrome and acute myeloid leukemia treated with allogeneic stem cell transplantation

Background After successful treatment of malignant diseases, therapy-related myelodysplastic syndrome and acute myeloid leukemia have emerged as significant problems. Design and Methods The aim of this study was to investigate outcome and risk factors in patients with therapy-related myelodysplastic syndrome or acute myeloid leukemia who underwent allogeneic stem cell transplantation. Between 1981 and 2006, 461 patients with therapy-related myelodysplastic syndrome or acute myeloid, a median age of 40 years and a history of solid tumor (n=163), malignant lymphoma (n=133), or other hematologic diseases (n=57) underwent stem cell transplantation and their data were reported to the European Group for Blood and Marrow Transplantation. Results The cumulative incidence of non-relapse mortality and relapse at 3 years was 37% and 31 %, respectively. In a multivariate analysis significant factors for relapse were not being in complete remission at the time of transplantation (p=0.002), abnormal cytogenetics (p=0.005), higher patients' age (p=0.03) and therapy-related myelodysplastic syndrome (p=0.04), while higher non-relapse mortality was influenced by higher patients' age. Furthermore, there was a marked reduction in non-relapse mortality per calendar year during the study period (p < 0.001). The 3-year relapse-free and overall survival rates were 33% and 35%, respectively. In a multivariate analysis significant higher overall survival rates were seen per calendar year (p < 0.001), for younger age (< 40 years) and normal cytogenetics (p=0.05). Using age (< 40 years), abnormal cytogenetics and not being in complete remission at the time of transplantation as risk factors, three different risk groups with overall survival rates of 62%, 33% and 24% could be easily distinguished. Conclusions Allogeneic stem cell transplantation can cure patients with therapy-related myelodysplastic syndrome and acute myeloid leukemia and has markedly improved over time. Non-complete remission, abnormal cytogenetics and higher patients' age are the most significant factors predicting survival.