Reduced-Intensity Conditioning Allogeneic Hematopoietic Cell Transplantation in Adults With Acute Myeloid Leukemia

Background: Acute myeloid leukemia (AML), whether de novo or arising from antecedent hematologic disorders in elderly patients, is less likely to be curable with standard chemotherapy regimens used for younger patients. Allogeneic hematopoietic cell transplantation (allo-HCT) is currently the most efficient anti-leukemia treatment for AML and has shown a survival advantage in younger patients with intermediate-or poor-risk cytogenetics. Methods: The authors review their experience as well as the published data regarding the role of reduced-intensity conditioning (RIC) allo-HCT in adults with AML. MEDLINE/PubMed and EMBASE/Ovid were searched, as well as reference lists of relevant articles, conference proceedings, and ongoing trial databases. Results: Elderly patients with AML have a poor survival for all cytogenetics subgroups (except for acute promyelocytic leukemia) and higher rates of transplant-related mortality with myeloablative allo-HCT. RIC regimens have been shown to decrease procedure-related toxicity and have emerged as an attractive treatment modality in AML patients not suitable for myeloablative conditioning regimens. While prospective data comparing outcomes of AML patients undergoing RIC allo-HCT vs conventional chemotherapy alone are not yet available, RIC allo-HCT is a reasonable option for high-risk older patients and for younger AML patients with medical comorbidities who achieve a first or subsequent remission. The application of RIC for patients with refractory disease or untreated relapse as well as the use of alternative donors should be considered within the context of clinical trials. Conclusions: RIC allo-HCT is a safe and effective treatment modality in high-risk elderly AML patients and in younger AML patients with medical comorbidities.