A multigene array for measurable residual disease detection in AML patients undergoing SCT

Area of Science:

• Hematology
• Oncology
• Molecular Diagnostics

Background:

• Acute myeloid leukemia (AML) is a complex malignancy with heterogeneous genetic causes.
• Identifying a single, sensitive marker for disease burden is difficult due to genetic diversity and potential for oligoclonality.
• Current methods for monitoring AML residual disease have limitations.

Purpose of the Study:

• To develop and validate a high-sensitivity multiple gene measurable residual disease (MG-MRD) assay for AML.
• To compare the efficacy of MG-MRD testing with traditional methods and WT1 RQ-PCR for predicting post-transplant outcomes.
• To assess the utility of MG-MRD in risk stratification for patients undergoing allogeneic stem cell transplantation (allo-SCT).

Main Methods:

• Development of a quantitative reverse transcription PCR (RQ-PCR) array for MG-MRD detection.
• Retrospective analysis of 74 patients who underwent allo-SCT between 1994-2012.
• Testing of peripheral blood samples for MG-MRD prior to transplantation.
• Comparison of MG-MRD results with bone marrow (BM)-based evaluations and WT1 RQ-PCR.

Main Results:

• MG-MRD testing on pre-transplant peripheral blood showed high concordance with traditional BM evaluation.
• MG-MRD testing demonstrated improved risk stratification for post-transplant relapse and overall survival (OS).
• Pre-SCT MG-MRD predicted all early relapses (within 100 days) post-allo-SCT, outperforming WT1 RQ-PCR (57% sensitivity).
• Nine WT1-negative patients were reclassified as high-risk by MG-MRD, experiencing 100% post-transplant mortality.

Conclusions:

• A multiple gene approach for measurable residual disease detection in AML is superior to using WT1 expression alone.
• MG-MRD testing provides a sensitive and accurate method for monitoring AML burden and predicting outcomes after allo-SCT.
• This study provides proof of principle for the clinical utility of MG-MRD in AML management.