FLT3 inhibitors and hematopoietic cell transplantation prolong survival in patients with FLT3-ITD-positive AML

Abstract

Acute myeloid leukemia (AML) is an aggressive hematological malignancy with genetic alterations. The FMS-like tyrosine kinase 3 (FLT3) gene is frequently mutated in adult de novo AML, with two types of mutations: internal tandem duplication (ITD) and point mutations in the tyrosine kinase domain. This study aimed to investigate the impact of FLT3 inhibitors and hematopoietic cell transplantation (HCT) on survival outcomes in patients with FLT3-ITD AML in a real-world setting. We retrospectively analyzed 139 patients with FLT3-ITD-positive AML between 2012 and 2021. The median age was 63 years. In the propensity score-matched cohort, FLT3 inhibitors improved overall survival (OS) compared with patients treated without FLT3 inhibitors (3-year OS: 33.7% vs. 25.8%, p = 0.021). Patients who underwent HCT had superior outcomes to those without HCT (3-year OS: 45.3% vs. 2.2%, p < 0.0001). The combination of FLT3 inhibitors and HCT resulted in the highest OS and relapse-free survival (RFS) rates (3-year OS: 62.4%; 3-year RFS: 67.2%). Disease status before transplantation did not predict the prognosis, but use of FLT3 inhibitors increased survival in patients without complete remission before HCT. These results demonstrate the clinical impact of FLT3 inhibitors on survival outcomes in patients with FLT3-ITD-positive AML, particularly when combined with HCT. FLT3 inhibitor can improve the prognosis of AML with FLT3 mutations, especially in patients who undergo HCT.