Improved minimal residual disease detection by targeted quantitative polymerase chain reaction inNucleophosmin 1type a mutated acute myeloid leukemia

PURPOSE (1) Quantification of minimal residual disease (MRD) by competitive CBFbeta/MYH11 reverse-transcriptase polymerase chain reaction (RT-PCR) in patients with acute myeloid leukemia (AML) and inversion(16) [inv(16)] during postremission therapy, (2) comparison of this method with conventional two-step RT-PCR, and (3) evaluation of a potential prognostic value. PATIENTS AND METHODS MRD of six consecutive adult patients with AML and inv(16)(p13;q22) or t(16;16)(p13;q22) who entered complete remission (CR) was monitored by competitive CBFbeta/MYH11 RT-PCR in their bone marrow (BM) during postremission therapy with high-dose cytarabine (HiDAC) or after BM transplantation with a matched unrelated-donor marrow (MUD-BMT) during an observation period of 4.5 to 27 months after initiation of treatment. RESULTS Competitive PCR showed a gradual decline by at least 4 orders of magnitude after 7 to 9 months in patients in continuous CR (CCR), while one patient who relapsed after 13.5 months only achieved a reduction by 2 orders of magnitude at the end of consolidation therapy. A rapid decrease below the detection limit was observed within 1 month in two patients after MUD-BMT. A temporary reappearance of molecular MRD was observed in these patients during immunosuppression for graft-versus-host disease (GvHD). After reduction of immunosuppression, the level of MRD dropped again below the PCR detection limit. Molecular monitoring by conventional two-step RT-PCR yielded comparable results only when multiple assays per time point were performed, while single-assay RT-PCR gave misleading results. CONCLUSION Competitive RT-PCR is a valuable tool for molecular monitoring during postremission chemotherapy, as well as after BMT.

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Sensitive NPM1 Mutation Quantitation in Acute Myeloid Leukemia Using Ultradeep Next-Generation Sequencing in the Diagnostic Laboratory

Archives of Pathology & Laboratory Medicine ◽

10.5858/arpa.2017-0229-oa ◽

2018 ◽

Vol 142 (5) ◽

pp. 606-612

Author(s):

Piers Blombery ◽

Kate Jones ◽

Ken Doig ◽

Georgina Ryland ◽

Michelle McBean ◽

...

Keyword(s):

Polymerase Chain Reaction ◽

Acute Myeloid Leukemia ◽

Myeloid Leukemia ◽

Residual Disease ◽

Chain Reaction ◽

Diagnostic Laboratory ◽

Npm1 Mutation ◽

Polymerase Chain ◽

Generation Sequencing ◽

Acute Myeloid

Context Detection of measurable residual disease after therapy is an important predictor of outcome in acute myeloid leukemia. Objective To investigate the feasibility of using next-generation sequencing (NGS) in the diagnostic laboratory to perform quantitative NPM1 mutation assessment using ultradeep (approximately 300 000×–500 000×) sequencing (NGS-qNPM1) as a method of assessing residual disease burden in patients with acute myeloid leukemia. Design A flexible NGS-based assay for the detection and quantitation of NPM1 mutations was developed by polymerase chain reaction amplification of target DNA sequences, sequencing on an Illumina (San Diego, California) MiSeq, and analyzing data with an in-house–designed bioinformatic pipeline. NGS-qNPM1 was compared with current NPM1 quantitation methods (real-time quantitative-polymerase chain reaction and multiparameter flow cytometry). Results The NGS-qNPM1 assay had a sensitivity of between 10−4 and 10−5 and showed high concordance and correlation with reference methodologies. Moreover, the NGS-qNPM1 assay was able to be integrated into the laboratory's existing, targeted amplicon-based sequencing workflow. Conclusions An NGS-based, quantitative NPM1-mutation assessment can be used to monitor patients with acute myeloid leukemia, and it has some practical advantages over existing modalities.

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