Flow cytometry and IG/TCR quantitative PCR for minimal residual disease quantitation in acute lymphoblastic leukemia:...

Area of Science:

• Hematology
• Oncology
• Clinical Diagnostics

Background:

• Minimal residual disease (MRD) quantification is crucial for therapeutic stratification in acute lymphoblastic leukemia (ALL).
• Allele-specific quantitative PCR (IG/TCR-QPCR) achieves robust sensitivity (≥0.01%) for MRD detection in ALL.
• The inter-center performance of multiparameter flow cytometry (MFC) for ALL MRD monitoring requires further evaluation.

Purpose of the Study:

• To prospectively compare the performance of IG/TCR-QPCR and MFC for MRD quantification in high-risk pediatric and adult ALL patients.
• To assess the concordance and complementarity of molecular and flow cytometry-based MRD detection methods.

Main Methods:

• A multicenter study prospectively analyzed 598 bone marrow samples from 238 ALL patients (102 pediatric, 136 adult).
• MRD was quantified using both IG/TCR-QPCR and 4/5-color MFC.
• Sensitivity of 0.01% was targeted for both methods.

Main Results:

• At diagnosis, suitable MRD markers were identified in 100% of patients by MFC (94%) and IG/TCR-QPCR (86%).
• Qualitative MRD results (<0.01% or ≥0.01%) concurred in 96% of evaluable samples (n=495).
• Quantitative MRD values ≥0.01% showed high correlation (r²=0.87) between methods.

Conclusions:

• Standardized IG/TCR-QPCR and MFC are comparable and highly complementary for ALL MRD monitoring.
• Concerted approaches for MFC standardization are recommended, similar to molecular MRD monitoring.
• These methods significantly contribute to achieving 100% MRD informativity in adult and pediatric ALL.