Related Experiment Video
Updated: May 23, 2026
Flow Cytometry to Estimate Leukemia Stem Cells in Primary Acute Myeloid Leukemia and in Patient-derived-xenografts, at Diagnosis and Follow Up
Published on: March 26, 2018
Detection of CD34, TdT, CD56, CD2, CD4, and CD14 by flow cytometry is associated with NPM1 and FLT3 mutation status
Bakul I Dalal1, Soudeh Mansoor, Mita Manna
1Division of Laboratory Haematology, Vancouver General Hospital, Vancouver, British Columbia, Canada. bakul.dalal@vch.ca
Unlabelled:
In 83 patients with cytogenetically normal acute myeloid leukemia (CN-AML), those with NPM1 and wild-type FLT3 (FLT3-wt) mutation and their poor prognostic combination had distinctive flow cytometric findings: CN-AML with a mutation of NPM1 (NPMI-Mt) were CD34(-), CD14(-), and CD2pos and CD4; those with FLT3-internal tandem duplications (ITD) were CD56pos, those with NPM1-Mt and FLT3-wt were CD34(-) and CD56(-); and those with poor prognostic combination NPM1-wt and FLT3-ITD were CD34pos and TdTpos.
Methods:
We retrospectively correlated NPM1 and FLT3 mutation status with flow cytometric profile of leukemic blasts in 83 adult patients with cytogenetically normal acute myeloid leukemia (CN-AML).
Results:
Mutation of the NPM1 gene (NPM1.mt) was found in 39 (47%) of 83 patients, and internal tandem duplication (ITD) of the FLT3 gene (FLT3-ITD) was seen in 38 (46%) of 83 patients. Patients with CN-AML and with NPM1.mt were less likely to express CD34 (33% vs. 93%; 2P = .0001), CD2 (0% vs. 14%; 2P = .0187), and CD14 (6% vs. 22%, 2P = .0476), and were more likely to express CD4 (65.5% vs. 37%; 2P = .0367) and CD19 (49% vs. 27%; 2P = .0506). The patients with CN-AML and with FLT3-ITD were more likely to express CD56 (47% vs. 23%; 2P = .0393). Moreover, patients with favorable prognostic combination of NPM1.mt and wild-type (wt) FLT3 (n = 18) were less likely to express CD34 (33% vs. 74% all others; 2P = .0021) and CD56 (6% vs. 37% all others; 2P = .0072). The group with an unfavorable prognostic combination of NPM1-wt and FLT3-ITD (n = 17) were more likely to express CD34 (88% vs. 45% all others; 2P = .0011) and TdT (40% vs. 2% all others; 2P = .0054).
Conclusions:
In patients with CN-AML, characteristic flow cytometric profile is associated with NPM1 and FLT3 mutation status.
Insights
Flow cytometry reveals distinct patterns in cytogenetically normal acute myeloid leukemia (CN-AML) based on NPM1 and FLT3 mutations. These findings aid in classifying CN-AML subtypes and predicting prognosis.
Area of Science:
- Hematology
- Molecular Biology
- Oncology
Background:
- Cytogenetically normal acute myeloid leukemia (CN-AML) is a heterogeneous disease.
- NPM1 and FLT3 mutations are key genetic alterations influencing CN-AML prognosis.
- Accurate subclassification of CN-AML is crucial for treatment decisions.
Purpose of the Study:
- To correlate NPM1 and FLT3 mutation status with specific flow cytometric profiles in CN-AML patients.
- To identify distinct immunophenotypic patterns associated with different NPM1/FLT3 mutation combinations.
- To explore the utility of flow cytometry in characterizing CN-AML subtypes.
Main Methods:
- Retrospective analysis of 83 adult CN-AML patients.
- Correlation of NPM1 and FLT3 mutation status with flow cytometric data of leukemic blasts.
- Statistical analysis to determine significant associations between mutations and antigen expression.
Main Results:
- NPM1 mutations were associated with decreased CD34, CD2, and CD14 expression, and increased CD4 and CD19 expression.
- FLT3-internal tandem duplications (ITD) were linked to increased CD56 expression.
- Favorable NPM1-mutated/FLT3-wild-type (wt) group showed lower CD34 and CD56 expression.
- Unfavorable NPM1-wt/FLT3-ITD group exhibited higher CD34 and TdT expression.
Conclusions:
- Characteristic flow cytometric profiles are associated with specific NPM1 and FLT3 mutation statuses in CN-AML.
- Flow cytometry can aid in the immunophenotypic classification of CN-AML based on genetic alterations.
- These findings support the integration of flow cytometry with molecular data for improved CN-AML characterization.
