[High dose treatments and preparatory regimens prior to haematopoietic stem cell transplantation]

High-dose chemotherapy can be defined as utilization of cytotoxic drug doses that produce bone marrow ablation. Transfusion of autologous graft serves as rescue from otherwise fatal myelotoxicity. Immune reaction of graft versus tumor that lowers relapse rates of malignant disease becomes an important contribution of allogeneic hematopoietic stem cell transplantation. New reduced intensity conditioning regimens with lower initial cytotoxicity rely on this immune effect with the potential of additional elimination of remaining cancer cells. Decreased toxicity of these regimens enables treatment of patients with comorbidity and/or in higher age.