Vol. 7, Issue 1, Part A (2025)

Purpose: Nucleophosmin1 (NPM1) and FMS-like tyrosine kinase-3 internal tandem duplication (FLT3-ITD) mutations influence the disease outcome in acute myeloid leukemia (AML). Newer molecular techniques, such as targeted next-generation sequencing (NGS), have better sensitivity and the ability to detect multiple mutations in a single run. However, their application is limited in resource-constrained setups. We aimed to analyze the prevalence of NPM1 and FTL3-ITD mutations in AML, vis-a-vis clinico-hematological characteristics, and compared conventional PCR with targeted NGS to detect FLT3-ITD mutations at diagnosis.
Methods: Conventional and real-time PCR were performed on 130 AMLs to detect FLT3-ITD and NPM1 mutations (A, B, or D mutations), respectively. Sanger sequencing was performed on 21 NPM1 mutated AMLs for subtyping. Targeted NGS (Ion Torrent platform) was also performed on 20 random samples to detect FLT3-ITD mutations.
Results: Fourteen (10.8%) patients had both mutations, 12 (9.2%) and 27 (20.8%) had isolated NPM1mutations and FLT3-ITD mutations, respectively. NPM1 mutant type A was detected in 90.5% (19/21) and type D in 9.5% (2/21) of patients. FLT3-ITD mutations were detected in 16 (31.3%) AML patients with recurrent cytogenetic abnormalities (AML-RCA) (p<0.01); however, none had NPM1 mutations. A comparison of PCR and targeted NGS showed concordance in 19/20 samples in detecting FLT3-ITD mutations, as well as good agreement (kappa ratio=0.8).
Conclusion: Compared to published data, the frequency of isolated NPM1 mutations was lower, while that of FLT3-ITD mutations was higher in our AML cohort. Conventional PCR (a cost-effective technique) compared well with targeted NGS (Ion Torrent platform) in detecting FLT3-ITD mutations.