Allogeneic hematopoietic cell transplantation improves outcome ofadults with t(6;9) acute myeloid leukemia: results from an internationalcollaborative study

摘要

Acute myeloid leukemia (AML) with t(6;9)(p22;q34) is a distinct entity accountingfor 1-2% of AML cases. A substantial proportion of these patients have aconcomitant -ITD. While outcomes are dismal with intensivechemotherapy, limited evidence suggests allogeneic hematopoietic celltransplantation (allo-HCT) may improve survival if performed early during firstcomplete remission. We report on a cohort of 178 patients with t(6;9)(p22;q34)within an international, multicenter collaboration. Median age was 46 years(range: 16-76), AML was in 88%, -ITD was present in 62%, and additionalcytogenetic abnormalities in 21%. Complete remission was achieved in81% (n=144), including 14 patients who received high-dose cytarabineafter initial induction failure. With a median follow up of 5.43 years,estimated overall survival at five years was 38% (95%CI:31-47%). Allo-HCT was performed in 117 (66%) patients, including89 in first complete remission. Allo-HCT in first complete remission wasassociated with higher 5-year relapse-free and overall survival as compared toconsolidation chemotherapy: 45% (95%CI: 35-59%) and53% (95%CI: 42-66%) 7%(95%CI: 3-19%) and 23% (95%CI: 13-38%),respectively. For patients undergoing allo-HCT, there was no difference inoverall survival rates at five years according to whether it was performed infirst [53% (95%CI: 42-66%)], or second[58% (95%CI: 31-100%); n=10] completeremission or with active disease/relapse [54% (95%CI:34-84%); n=18] ( =0.67). Neither -ITD nor additional chromosomal abnormalities impactedsurvival. In conclusion, outcomes of t(6;9)(p22;q34) AML are poor withchemotherapy, and can be substantially improved with allo-HCT.