The 2010 and 2017 editions of the European LeukemiaNet (ELN) recommendations for diagnosis and management of acute myeloid leukemia (AML) in adults are widely recognized among physicians and investigators. There have been major advances in our understanding of AML, including new knowledge about the molecular pathogenesis of AML, leading to an update of the disease classification, technological progress in genomic diagnostics and assessment of measurable residual disease, and the successful development of new therapeutic agents, such as FLT3, IDH1, IDH2, and BCL2 inhibitors. These advances have prompted this update which includes a revised ELN genetic risk classification, revised response criteria, and treatment recommendations.

Although nonmyeloablative conditioning regimen transplantations (NMTs) induce engraftment of allogeneic stem cells with a low spectrum of toxicity, graft-versushost disease (GVHD) remains a significant cause of morbidity and mortality. In vivo T-cell depletion, using alemtuzumab, has been shown to reduce the incidence of GVHD. However, this type of maneuver, although reducing GVHD, may have an adverse impact on disease response, because NMTs exhibit their antitumor activity by relying on a graft-versus-malignancy effect. To explore the efficacy of alemtuzumab compared with methotrexate (MTX) for GVHD prophylaxis, we have compared the results in 129 recipients of a sibling NMT enrolled in 2 prospective studies for chronic lymphoproliferative disorders. Both NMTs were based on the same combination of fludarabine and melphalan, but the United Kingdom regimen (group A) used cyclosporin A plus alemtuzumab, whereas the Spanish regimen (group B) used cyclosporin A plus MTX for GVHD prophylaxis. Patients receiving alemtuzumab had a higher incidence of cytomegalovirus (CMV) reactivation (85% versus 24%, P < .001) and a significantly lower incidence of acute GVHD (21.7% versus 45.1%, P ‫؍‬ .006) and chronic GVHD (5% versus 66.7%, P < .001). Twenty-one percent of patients in group A and 67.5% in group B had complete or partial responses 3 months after transplantation (P < .001). Eighteen patients in group A received donor lymphocyte infusions (DLIs) to achieve disease control.At last follow-up there was no difference in disease status between the groups with 71% versus 67.5% (P ‫؍‬ .43) of patients showing complete or partial responses in groups A and B, respectively. No significant differences were observed in event-free or overall survival between the 2 groups. In conclusion, alemtuzumab significantly reduced GVHD but its use was associated with a higher incidence of CMV reactivation. Patients receiving alemtuzumab often required DLIs to achieve similar tumor control but the incidence of GVHD was not significantly increased after DLI. (Blood. 2002;100: 3121-3127)