IDH1 Mutations in Acute Myeloid Leukemia: Frequency and Clinical Features in the Context of FLT3 and NPM1 Co-Mutations—A Single-Center Study from Turkey

The prognostic relevance of IDH1 mutations remains unclear in acute myeloid leukemia (AML). This study, representing the first Turkish AML cohort characterized for IDH1 mutations, aimed to determine the frequency of IDH1, FLT3 and NPM1 mutations and to describe the associated clinical characteristics. We retrospectively analyzed clinical, cytogenetic, and molecular data for 57 AML patients. Bone marrow aspirates were evaluated cytogenetically using G-banding, and molecular mutations were assessed by PCR or NGS (MiSeq-Illumina). IDH1 mutations were detected in 7% of patients; FLT3 and NPM1 mutations were detected in 38.6% and 19.3% of patients, respectively. A significant positive correlation existed between IDH1 and NPM1 mutations (r = 0.388, p = 0.003). Overall mortality was 56.1% and remission was achieved in 43.9%. Older age (p = 0.029) and comorbidities (p = 0.009) were significantly linked to mortality. Mortality was 100% in the four IDH1-mutant patients and significantly higher in NPM1-mutant patients. Overall survival was shorter in IDH1-mutants, although the difference did not reach statistical significance (log-rank p = 0.057). Relapse occurred in 26.3%, rising to 50% in the IDH1-mutated subgroup. In this limited cohort, IDH1-mutant cases were associated with shorter overall survival and higher mortality; however, the small number of IDH1-mutant patients (n = 4) precludes definitive prognostic conclusions. Outcomes in NPM1-mutated patients were also less favorable than typically expected, possibly related to co-occurring IDH1 mutations. These descriptive findings characterize the molecular landscape of AML in an underrepresented Turkish population and may provide a foundation for larger, multicenter studies rather than confirming a prognostic role for these mutations.