Comparison of Multiparameter Flow Cytometry Immunophenotypic Analysis and Quantitative RT-PCR for the Detection of Minimal Residual Disease of Core Binding Factor Acute Myeloid Leukemia.

Abstract

To examine the value of minimal residual disease (MRD) by multiparameter flow cytometry (MFC) in core binding factor (CBF) acute myeloid leukemia (AML). We studied 42 patients with t(8;21)(q22;q22)/RUNX1-RUNX1T1 and 51 with inv(16)(p13.1q22)/CBFB-MYH11 Tandem MRD analyses by MFC and quantitative reverse transcription polymerase chain reaction (qRT-PCR) were performed in 281 bone marrow (BM) samples. Grouping qRT-PCR levels as ≤0.01, 0.01 to 0.1, 0.1 to 1, 1 to 10, and >10%, and reporting MFC (sensitivity, 0.1%-0.01%) as positive or negative, κ coefficient test showed no agreement between qRT-PCR and MFC in BM samples obtained postinduction (n = 44, κ = 0.041), and only weak agreement during consolidation (n = 108, κ = 0.083), maintenance/follow-up (n = 107, κ = 0.164), and salvage chemotherapy (n = 24, 0.376). In the post induction BM samples, while qRT-PCR <0.1% was associated with lower and ≥10% with higher AML relapse risk (P = .035), qRT-PCR between 0.1% to 1% and 1% to 10% failed to predict relapse. In the latter group with intermediate qRT-PCR results, MFC provided prognostic value for relapse (P = 0.006). MFC and qRT-PCR are complementary tests in monitoring CBF AML MRD.