TREATMENT OF HEMATOLOGICAL MALIGNANCIES RELAPSING AFTER ALLOGENEIC BONE-MARROW TRANSPLANTATION

The rate of relapse after allogeneic bone marrow transplantation (BMT) varies between 15 and 60%. New therapeutic strategies are required ur gently as no significant results have been obtained with standard chem otherapy. The best results of second allogeneic BMT have been obtained when the interval between the first and the second transplant was mor e than 6 to 20 months, depending on the study. Veno-occlusive disease was an important cause of non-leukemic death (13-65%). As the toxicity of second BMT is very high, other treatments have been considered: co mplete remissions were reported after sudden discontinuation of the im munosuppressive therapy. Interferon-alpha has been used for chronic my eloid leukemia patients and may achieve hematological and cytogenetic complete remission. More recently, donor leucocytes transfusions have been proposed and at least in some cases, have led to molecular comple te remission (polymerase chain reaction,vith double amplification) in chronic myeloid leukemia patients. However, non predictable marrow apl asias and graft-versus-host reactions hamper the efficacy of this stra tegy. Finally, hemopoietic growth factors used to promote donor cell g rowth produce interesting results which deserve further studies.