Application of bone marrow transplantation in leukaemia and aplastic anaemia

Abstract

Marrow transplantation is effective treatment for a number of haematological diseases in patients under the age of 50 who have an HLA-identical sibling donor. It is generally successful when used early in the treatment of aplastic anaemia. It is the only treatment that offers long-term disease-free survival for patients with acute leukaemia who have relapsed at least once, with 10-30 per cent apparent cures. Although still somewhat controversial, it appears also to be the treatment of choice for patients with acute non-lymphoblastic leukaemia in first chemotherapy induced remission and for those with chronic myelogenous leukaemia in the chronic phase since approximately 50-60 per cent of these patients are surviving after marrow transplantation in complete remission, apparently cured. Marrow grafting is the only effective treatment for many patients with inherited immunological-deficiency diseases and certain genetic storage diseases. It is being explored for the therapy of patients with lymphoma, Hodgkin's disease, multiple myeloma, small-cell lung cancer, testicular cancer, ovarian cancer and genetic disorders of haematopoiesis. Cures of congenital Fanconi anaemia, Blackfan-Diamond anaemia, osteopetrosis, and paroxysmal nocturnal haemoglobinuria have been achieved by marrow grafting. Genetic disorders associated with haemolytic anaemia and cyclic neutropenia have been cured by marrow grafting in animals. Target disorders for marrow transplantation in humans are thalassaemia major and sickle cell disease, and, indeed, a first successful transplant for treatment of thalassaemia major has recently been described (Thomas et al, 1982). Marrow transplantation has been limited by the fact that many patients do not have HLA-identical siblings and very few have monozygotic twins. The Seattle team has now explored the use of less well-matched family member donors in more than 80 patients with leukaemia. These donors share one HLA haplotype genetically with the patient and are phenotypically identical at two of the three major HLA loci on the other HLA haplotype (Clift et al, 1979). Overall, the post-transplant survival appears more a reflection of the type and stage of the leukaemia than of the marrow donor. Patients with leukaemia grafted in relapse have a projected survival of 20-30 per cent and those transplanted in remission of 50 per cent. The incidence and severity of GVHD may not be significantly different from that of patients given HLA-identical sibling marrow grafts.(ABSTRACT TRUNCATED AT 400 WORDS)