KIT Mutant/Core binding factor-negative acute myeloid leukemia might be a complex subgroup with dismal prognosis: a single-center retrospective analysis

KIT mutations are well-established as poor prognostic markers in core binding factor AML (CBF AML). However, data on KIT mutation in CBF-negative (CBF-neg) AML remains scarce. This retrospective study aimed to characterize the clinical features and outcomes of patients with KIT mutant (KIT mut)/CBF-neg AML. We conducted a retrospective study in our single center and identified non-M3 de novo AML with KIT mutations by next-generation sequencing (NGS) from January 2018 to June 2024. Core binding factor (CBF) AML or patients with underlying systemic mastocytosis were excluded. The clinical data of KIT mut/CBF-neg AML was collected and analyzed. 45 patients were enrolled in the cohort, including 3 patients with secondary AML. The median variant allele frequency (VAF) of KIT mutation was 41.2% and the most frequent comuations were CEBPA (27/45, 60%), WT1 (12/45, 26.7%) and NRAS (11/45, 24.4%). After a median follow-up of 48 months, the median event-free survival (EFS) and overall survival (OS) of the cohort was 15.3 months and 24.1 months, respectively. Patients with KIT exon 17 mutations tended to harbor an inferior EFS and OS. In conclusion, KIT mutant/CBF-neg AML was a complex subgroup with dismal prognosis and NIT might bring benefits for those patients.