Measurable Residual Disease in IDH-Mutated AML: Identifying a Clinically Relevant Threshold for IDH Mutation Monitoring
In brief
A 0.2% IDH mutation threshold flagged AML patients at higher relapse risk
In a single-center study, patients with post-treatment IDH mutation levels at or above 0.2% had a 2-year relapse incidence of 63.6%, compared with 20% below the threshold. The test also found residual clones in 56% of patients whose flow cytometry was negative, but low-level signals were common; the cutoff needs validation in larger studies.
- Journal
- European journal of haematology (Q1)
- Published
- 2 November 2026
- Study design
- Case-control study
- Evidence level
- Level 3, Low (CEBM 3b)
- Authors
- Guillermo Ramil, Elena Bussaglia, Helena Castellet, Guadalupe Oñate, Ana Garrido, Maite Carricondo, et al.
- PMID
- 42971929
- DOI
- 10.1111/ejh.70351
Why clinicians should know about it
- Picked for Biochemistry (medical) (top studies of the week, 8 November 2026): Clinical validation of IDH assay performance and MRD threshold
Abstract
BACKGROUND: Isocitrate dehydrogenase (IDH) mutations are recurrent in acute myeloid leukemia (AML) and represent promising targets for measurable residual disease (MRD) monitoring. However, clinically validated strategies for IDH-based MRD assessment remain lacking. METHODS: We evaluated the analytical performance and clinical utility of droplet digital PCR (ddPCR) for IDH mutation monitoring in a single-center cohort of patients with IDH-mutated AML treated with curative intent. Healthy controls were included to characterize low-level background signals and identify a clinical threshold. RESULTS: ddPCR showed robust analytical performance, with a limit of detection of 0.01% variant allele frequency (VAF) and strong concordance with NGS. Low-level IDH mutation signals were frequently detected in healthy individuals and in patients in remission. We identified 0.2% VAF as a candidate threshold for clinically relevant IDH MRD. Using this cutoff, post-treatment detectable IDH MRD was associated with a higher 2-year cumulative incidence of relapse (63.6% vs. 20%; p = 0.019) and inferior overall survival (70.6% vs. 92.9%; p = 0.04). Among patients negative by multiparameter flow cytometry, ddPCR identified residual IDH-mutated clones in 56% of cases, who showed higher relapse rates than double-negative patients (50% vs. 0%; p = 0.031). CONCLUSIONS: A 0.2% VAF threshold was associated with clinically distinct outcomes and may provide a useful framework for IDH-based MRD assessment in AML.
Abstract as published, via PubMed.
For healthcare professionals. The summary is generated by AI from the published abstract, and the evidence level is assigned automatically from the study design on the Oxford CEBM hierarchy. Neither is medical advice. Read the full paper before changing practice.