Durable remission following donor lymphocyte infusion for post-transplant relapse of acute myeloid leukemia developing from secondary myelofibrosis

Abstract

Essential thrombocythemia gradually developed into secondary myelofibrosis and progressed to leukemia eight months later in a 53-year-old man. After remission induction therapy, he achieved remission by undergoing allogeneic hematopoietic stem cell transplantation from unrelated patients in non-remission. However, peripheral blood WT-1 mRNA gradually increased, and the disease relapsed three years and six months after transplantation. He was taking prednisolone (7.5 mg) and tacrolimus (5 mg) for chronic pulmonary graft-versus-host disease (GVHD) and was reluctant to reduce or discontinue immunosuppressive drugs; therefore, donor lymphocyte infusion (DLI) was performed for a total of five times. Four months after the fifth DLI, cutaneous GVHD appeared, a slow decrease in WT-1 mRNA was observed, and blasts in the peripheral blood disappeared. One year and three months after the last DLI, he achieved complete remission. Although DLI for post-transplant relapse in patients with secondary myelofibrosis or leukemia is rare, it can be beneficial for post-relapse therapy.