Favorable Long-Term Outcomes after Allogeneic Transplantation for Elderly Patients with Myelodysplastic Syndromes: A Report from the Chronic Malignancies Working Party of EBMT

Introduction:Communicating about the risk of mortality after allogeneic hematopoietic stem cell transplantation (HCT) is a challenging task for physicians. This is especially true for elderly patients with aggressive hematologic malignancies. Mortality after HCT may be split in three major parts, death after relapse, therapy-related mortality (including late complications of previous treatments of the hematologic malignancies) and background or general population mortality from causes unrelated to the treatment or disease. In the framework of the competing endpoints, relapse and non-relapse mortality, background mortality mainly determines the magnitude of non-relapse mortality. To estimate the size of the background mortality, the risk of an age-, sex-, country- and calendar year matched population can be used as approximation. This can be done with methods from relative survival analysis. By nature, background mortality increases among elderly patients. In order to study the size of background and excess mortality we analyzed mortality in a population of adult transplant recipients with myelodysplastic syndromes (MDS) because this indication is characterized by a high median age already at diagnosis and large numbers of transplanted patients.