Donor leukocyte infusions in the treatment of chronic myeloid leukemia in relapse post bone marrow transplantation.

A 25-yr-old Caucasian man presented in 1988 with Philadelphia chromosome (Ph) negative, bcr-abl rearranged, chronic phase chronic myeloid leukemia (CML). He was treated with human leukocyte antigen matched sibling allogeneic bone marrow transplantation but relapsed 5 yrs later. At this time he was given donor leukocyte infusions from the original bone marrow donor, seeking an immune anti-leukemic effect. This treatment induced graft versus host disease and severe bone marrow aplasia, requiring immunosuppression and repeat donor marrow infusion (without prior conditioning). Graft versus host disease was controlled and full donor hematopoiesis was restored, resulting in complete eradication of the leukemic clone at a molecular level. The patient remains in complete clinical and molecular remission and off all immunosuppression 24 mths later. This emphasizes a potentially powerful graft versus leukemia effect in CML.