Allotransplants for Patients 65 Years or Older with High-Risk Acute Myeloid Leukemia

The outcome of persons > 65 years with acute myeloid leukemia (AML) is poor. A transplant from an HLA-identical sibling or an HLA-matched unrelated donor can cure some of these patients but is associated with a substantial transplant-related mortality and a high relapse risk. We analyzed 185 subjects > 65 years with high-risk AML receiving conventional (n = 42) or reduced-intensity (n = 143) pretransplant conditioning and a transplant from an HLA-identical sibling (n = 66) or a 10/10 loci HLA-matched unrelated donor (n = 119). Two-year survival was 37%. Subjects with serious adverse events during before chemotherapy for their leukemia had a poor outcome after stem cell transplantation. Patients who had active leukemia or measurable residual disease (MRD) before transplantation had a worse outcome. Delayed hematologic recovery after induction or consolidation chemotherapy, high-risk AML genetics, donor-recipient HLA-DRβ3/4/5-DP mismatches, and history of cardiovascular disease were also correlated with survival in multivariate analyses. The 57 MRD-negative patients with few other adverse prognostic factors had an excellent outcome (2-year overall survival, 76%), whereas the 58 patients with detectable leukemia and more than 1 other additional factor fared poorly (2-year overall survival, 8%). These data indicate it is possible to identify persons > 65 years with high-risk AML likely to benefit from an allotransplant. Validation of this prediction is needed.