A frequent reason that malignant tumours and leukaemia therapy failure is the fact that oncologists could not use adequate doses of radiation and chemotherapy treatments. Higher doses would irreversibly damage haematopoietic cells, which are necessary for life. On the other side low doses of radiation or chemotherapy are often not able to destroy all cancer cells. After some time the cells multiply again, and in addition they are usually more resistant to therapy, so a relapse of cancer disease occurs.

          Transplantation of haematopoietic cells starts with intensive radiation and/or chemotherapy treatment, which destroy all the tumorous cells, but haematopoietic cells in bone marrow also. Afterward they are replaced with healthy haematopoietic cells (transplantation itself). If the transplantation succeeds and new haematopoietic cells correctly start their function, the patient can be cured. It is not only a question of life-lengthening therapy, but it’s a question of the patient’s recovery. Relapse of primary malignant disease after transplantation is rare.

          The treatment of non-malignant diseases with haematopoietic cells transplantation proceeds in the same way, in this case the aim is to destroy the haematopoietic or immune competent cells that do not correctly fulfil their function.