A QA Program for MRD Testing Demonstrates That Systematic Education Can Reduce Discordance Among Experienced...

Area of Science:

• Clinical Cytometry
• Hematologic Oncology
• Immunophenotyping

Background:

• Minimal residual disease (MRD) by flow cytometry (FCM) is a key prognostic factor in pediatric B-cell lymphoblastic leukemia (B-ALL).
• Standardization of MRD testing by the Children's Oncology Group (COG) exists, but implementation in routine clinical laboratories is inconsistent.
• The Foundation for National Institutes of Health aimed to harmonize MRD measurement across diverse laboratory settings.

Purpose of the Study:

• To assess the feasibility of harmonizing MRD testing for B-ALL across multiple North American laboratories.
• To evaluate the impact of standardized protocols and educational interventions on MRD detection accuracy.
• To identify challenges in routine clinical MRD analysis, including hematogone identification.

Main Methods:

• Listmode FCM data from B-ALL patient marrows were distributed to seven clinical laboratories.
• Laboratories received the COG standardized MRD analysis protocol and underwent educational sessions.
• Performance was evaluated through analysis of initial and subsequent case challenges.

Main Results:

• Initial discordance rates reached 26% across 105 challenges.
• After standardization and education, discordance decreased to 9% in the final round (70 challenges).
• Hematogones continued to be misclassified as MRD in some instances, highlighting persistent challenges.

Conclusions:

• Standardized protocols alone are insufficient; educational components are vital for accurate B-ALL MRD analysis by FCM.
• Dissemination of MRD testing to routine clinical labs is achievable with supplementary education.
• Improved training is necessary to address challenges like hematogone recognition for consistent MRD assessment.