Bunjes, Donald

Abstract Abstract 680 Cytogenetics play an essential role in determining the prognosis of patients with AML. However, there is still no validated cytogenetics grouping scheme that specifically applies to patients undergoing allogeneic stem cell transplantation, which hampers accurate prognostication and risk stratification. We studied 821 adult patients (median age 41, range 18–74) who underwent SCT between 1999 and 2004 for AML (excluding APL) in CR1 or CR2 and who were reported to the CIBMTR from centers with >20 patients meeting study criteria. 75% of patients received a myeloablative conditioning. 496 patients had a normal karyotype. The primary cytogenetics reports were manually reviewed for 92% of the patients with an abnormal karyotype. We compared the ability of the 6 existing grouping schemes (MRC, CALGB, EORTC/GIMEMA, SWOG/ECOG, DFCI, and Monosomal Karyotype (MK) classifications) to stratify patients, using both the Akaike Information Criterion in multivariable models and the C-statistic. Among all existing schemes, the DFCI system provided a marginally superior stratification for overall and leukemia-free survival. We also built a new classification using individual cytogenetic abnormalities in a Cox model that included other significant covariates (performance status, therapy-related disease, conditioning intensity, graft source, donor match, duration of CR1, and gender match). This CIBMTR scheme (see Table), which is similar to the DFCI scheme except for the inclusion of patients with t(8;21) in the intermediate group, could stratify patients into 3 groups with similar treatment-related mortality but significantly different overall survival, leukemia-free survival, and incidence of relapse. This scheme appeared to apply to both patients in CR1 and in CR2 (see FiguresF2). This transplant-specific scheme could be adopted for prognostication purposes and to stratify patients with karyotypic abnormalities entering transplantation clinical trials. Future studies may clarify the relative outcome of patients with t(8;21) and refine this scheme with the inclusion of molecular abnormalities. Disclosures: No relevant conflicts of interest to declare.

BACKGROUNDPatients with FMS like tyrosine kinase 3 (FLT3)‐mutated acute myeloid leukemia (AML) have a poor prognosis and are referred for early allogeneic hematopoietic stem cell transplantation (HCT).METHODSData from the Center for International Blood and Marrow Transplant Research (CIBMTR) were used to evaluate 511 adult patients with de novo AML who underwent HCT during 2008 through 2011 to determine whether FLT3 mutations had an impact on HCT outcomes.RESULTSIn total, 158 patients (31%) had FLT3 mutations. Univariate and multivariate analyses revealed an increased risk of relapse at 3 years in the FLT3 mutated group compared with the wild‐type (WT) group (38% [95% confidence interval (CI), 30%‐45%] vs 28% [95% CI, 24%‐33%]; P = .04; relative risk, 1.60 [95% CI, 1.15‐2.22]; P = .0048). However, FLT3 mutation status was not significantly associated with nonrelapse mortality, leukemia‐free survival, or overall survival. Although more patients in the FLT3 mutated group died from relapsed primary disease compared with those in the WT group (60% vs 46%), the 3‐year overall survival rate was comparable for the 2 groups (mutated group: 49%; 95% CI, 40%‐57%; WT group: 55%, 95% CI, 50%‐60%; P = .20).CONCLUSIONSThe current data indicate that FLT3 mutation status did not adversely impact overall survival after HCT, and about 50% of patients with this mutation who underwent HCT were long‐term survivors. Cancer 2016;122:3005‐3014. © 2016 American Cancer Society.