Characteristics and Outcome of FLT3-ITD-Positive Acute Myeloid Leukemia.

Backgrounds: AML patients with FLT3-ITD mutation experience a poor prognosis. Our study evaluated the clini¬cal characteristics, remission, relapse, and clinical outcomes of these patients. We also assessed the effectiveness of allogeneic hematopoietic stem cell transplantation (allo-HSCT) and sorafenib in treating AML patients with FLT3-ITD mutation.

Methods: Fifty-five newly diagnosed AML patients with FLT3-ITD mutation in our center were retrospectively enrolled between January 2018 and June 2023. Multiple fusion genes and gene mutations were identified for the diagnosis of AML. Survival curves were calculated by employing the Kaplan-Meier method, and the differences between them were evaluated by using the log-rank (Mantel-Cox) test.

Results: Twenty-seven patients underwent allo-HSCT. The allo-HSCT group had a significantly extended follow-up period compared to the non-HSCT group (p < 0.001). Mutations in both NPM1 and FLT3-ITD were present in 18 out of the 55 patients (32.7%). Among them, eleven patients were given sorafenib plus chemotherapy induction therapy, and forty-four received mono-chemotherapy. The HSCT group had a higher overall survival (OS) rate than the non-HSCT group (p < 0.001), and a higher relapse-free survival (RFS) rate as well (p = 0.0017). No statistically significant difference in OS and RFS was observed when compared with sorafenib plus chemotherapy and mono-chemotherapy (p > 0.05). FLT3-ITD-positive patients with and without NPM1 mutation did not experience a significant difference in OS and RFS rates (p > 0.05).

Conclusions: Allo-HSCT immediately following complete remission could improve outcomes for young adults diagnosed with FLT3-ITD-positive AML. However, we found no statistical difference in the overall response rate (ORR) and clinical outcome between sorafenib combined with chemotherapy and chemotherapy alone.