Significance of Persistent Cytogenetic Abnormalities on Myeloablative Allogeneic Stem Cell Transplantation in First Complete Remission

Risk stratification is important to identify patients with acute myelogenous leukemia (AML) who might benefit from allogeneic hematopoietic stem cell transplantation (allo-HSCT) in first complete remission. We retrospectively studied 150 patients with AML and diagnostic cytogenetic abnormalities who underwent myeloablative allo-HSCT while in first complete remission to evaluate the prognostic impact of persistent cytogenetic abnormalities at allo-HSCT. Three risk groups were identified. Patients with favorable/intermediate cytogenetics at diagnosis (n = 49) and patients with unfavorable cytogenetics at diagnosis but without a persistent abnormal clone at allo-HSCT (n = 83) had a similar 3-year leukemia-free survival of 58%-60% despite the higher 3-year relapse incidence (RI) in the latter group (32.3%, versus 16.8% in the former group). A third group of patients with unfavorable cytogenetics at diagnosis and a persistent abnormal clone at allo-HSCT (n = 15) had the worst prognosis, with a 3-year RI of 57.5% and 3-year leukemia-free survival of only 29.2%. These data suggest that patients with AML and unfavorable cytogenetics at diagnosis and a persistent abnormal clone at allo-HSCT are at high risk for relapse after allo-HSCT. These patients should be considered for clinical trials designed to optimize conditioning regimens and/or to use preemptive strategies in the posttransplantion setting aimed at decreasing RI.