Treatment of leukemia in relapse after bone marrow transplantation

To the Editor: The prognosis of patients with a relapse of leukemia within the first year after allogeneic bone marrow transplantation is dismal. Giralt et al. (Sept. 9 issue)¹ described seven patients whose leukemia had relapsed after allogeneic bone marrow transplantation. All were treated with granulocyte colony-stimulating factor (filgrastim) to induce terminal differentiation of the leukemic clone, selectively stimulate donor hematopoietic cells, and enhance the graft-versus-leukemia reaction. Three of the seven patients had a complete response, with reestablishment of hematopoiesis of donor origin. We observed such a trend toward a lower relapse rate in patients treated with recombinant granulocyte-macrophage colony-stimulating.