INTERNATIONAL JOURNAL OF RESEARCH AND INNOVATION IN SOCIAL SCIENCE (IJRISS)
ISSN No. 2454-6186 | DOI: 10.47772/IJRISS | Volume IX Issue XI November 2025
Comparison of Euroflow and Conventional Flow Cytometry
Protocols for Minimal Residual Disease Detection in Pediatric B-Cell
Acute Lymphoblastic Leukemia
Maldonado N, Katherine., Mamani C, William
Instituto Regional de Enfermedades Neoplásicas del sur – IREN SUR
Received: 10 November 2025; Accepted: 20 November 2025; Published: 02 December 2025
ABSTRACT
Acute Lymphoblastic Leukemia (ALL) is the most frequent hematological malignancy in childhood, and its
prognosis is strongly linked to the monitoring of Minimal Residual Disease (MRD). Flow cytometry (FC) is the
gold standard for MRD detection, but methods vary widely between laboratories, often leading to discrepancies
in sensitivity and reliability. This study aimed to quantitatively and qualitatively compare two flow cytometry
protocols—the standardized EuroFlow method and a conventional, laboratory-developed protocol—for MRD
detection in pediatric B-cell ALL patients. A total of 228 bone marrow samples from 76 pediatric patients at
IREN SUR were analyzed. The results, benchmarked against an external reference (INSNSB protocol), showed
that 35.5% of patients were MRD-positive, predominantly in the female and older pediatric (11–15 years)
subgroups. The EuroFlow protocol demonstrated a consistent 100% accuracy across all age and sex strata,
whereas the conventional method showed diminished accuracy, falling to 83.3% in the female 11–15 years
group. Crucially, both protocols maintained 100% specificity (precision). Correlation analysis indicated perfect
diagnostic concordance for EuroFlow (kappa=1.000) and superior quantitative correlation with the reference for
normal B-lymphoblasts (R=0.9798). These findings conclusively establish EuroFlow as the more reliable and
robust protocol for MRD detection in a clinical setting, recommending its adoption to standardize diagnostic
practice and improve relapse prediction.
Keywords: Acute lymphoblastic leukemia, minimal residual disease, flow cytometry, EuroFlow,
standardization.
INTRODUCTION
Acute Lymphoblastic Leukemia (ALL) remains the most prevalent cancer among children worldwide.
Advancements in multi-agent chemotherapy have dramatically improved five-year survival rates, which now
approach 90% in high-income countries. However, relapse continues to be the leading cause of treatment failure
and mortality. The accurate and timely detection of residual leukemic cells, known as Minimal Residual Disease
(MRD) or Measurable Residual Disease (MRD), is universally recognized as the single most critical prognostic
factor in ALL management [7], [9]. MRD status—typically defined by a threshold of ≥ 0.01% or 10-4 leukemic
cells—guides risk stratification and treatment intensity adjustments, particularly in post-induction and
consolidation phases.
Multiparametric Flow Cytometry (MFC) has become the preferred technique for MRD monitoring due to its
high sensitivity (capable of detecting 10-4 to 10-5 cells), speed, and relatively low cost compared to molecular
methods like PCR [11]. MFC allows for precise characterization of leukemic cells by simultaneously analyzing
multiple antigenic markers to identify aberrant and immature cell populations. It relies on identifying Leukemia-
Associated Immunophenotypes (LAIPs) or tracking the aberrant expression patterns of B-cell precursor antigens,
such as CD10, CD19, CD34, and CD45, to discriminate between residual leukemic blasts and normal
regenerating B-cell precursors [8].
Despite its utility, a major challenge in MFC for MRD is the high variability in results across laboratories, often
stemming from differences in antibody panels, sample preparation, compensation settings, and data analysis
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