Flow Cytometric Analysis of Peripheral Blood Neutrophil Myeloperoxidase Expression and Myelodysplastic Syndromes

Summary

Myelodysplastic syndromes (MDS) constitute a heterogeneous group of clonal bone marrow neoplasms that predominate in the elderly, with a median age at diagnosis of 70 years. MDS are characterized by peripheral blood cytopenia and morphologic dysplasia for one or more hematopoietic cell lineage, reflecting ineffective hematopoiesis.

The diagnostic work-up of MDS includes a bone marrow aspirate and biopsy, which is an invasive procedure, for cytomorphologic and cytogenetic evaluations. Because the prevalence of disease is lower than 20% in subjects referred for suspected MDS, many patients are exposed to unnecessary bone marrow aspiration-related discomfort and harms.

An objective assay is highly desirable for accurately ruling out MDS based on peripheral blood samples, which may obviate the need for invasive bone marrow aspiration and biopsy in patients with negative results.

Few studies have investigated the value of peripheral blood flow cytometric analysis for the diagnosis of MDS and/or chronic myelomonocytic leukemia (CMML). Although promising, these studies lacked replication of their results, used a case-control design, which was prone to spectrum bias, or yielded imprecise diagnostic accuracy estimates due to relatively limited sample sizes.

Anecdotal evidence supports the potential of flow cytometric analysis of peripheral blood neutrophil myeloperoxidase expression for the diagnosis of MDS and CMML. Myeloperoxidase is an enzyme synthetized during myeloid differentiation that constitutes the major component of neutrophil azurophilic granules. Myeloperoxidase expression may reflect neutrophil hypogranulation, which is a classical although subjective dysplastic feature of MDS. Flow cytometric analysis of myeloperoxidase expression in bone marrow neutrophil granulocytes has been used for discriminating low versus high grade MDS. Yet a study reporting on the accuracy of flow cytometric analysis of peripheral blood neutrophil myeloperoxidase expression for the diagnosis of MDS is still lacking, to our knowledge.

In this study, the investigators hypothesize that flow cytometric analysis of neutrophil myeloperoxidase expression in peripheral blood may accurately rule out MDS and obviate the need for bone marrow aspiration and biopsy, with sensitivity approaching 100%, in routine practice.

In this observational diagnostic accuracy study, burden will be null for recruited patients. No specific intervention is assigned to participants. All diagnostic testing, procedures, and medication ordering are performed at the discretion of attending physicians. Flow cytometry analysis of peripheral blood neutrophil myeloperoxidase expression will not require additional blood sample. A test result will have no impact on patient management. No follow-up visits are planned in this cross-sectional study.

Conditions

• Myelodysplastic Syndromes
• Chronic Myelomonocytic Leukemia

Interventions

DIAGNOSTIC_TEST

Flow cytometry analysis of neutrophil myeloperoxidase expression

Flow cytometry analysis of neutrophil myeloperoxidase expression in peripheral blood samples will be performed within 24 h of MDS diagnostic evaluation and blinded to the reference standard. Peripheral blood samples will be collected in 5 ml (EDTA) anticoagulant plastic tubes and processed within 24 h maximum of collection. The samples will be stored at 4°C overnight. Blood samples containing at least 105 neutrophils will be incubated with a panel of antibodies conjugated to fluorochromes, according to the manufacturers' recommendations. At least 10,000 cell events will be acquired on a 3-laser, 8-color flow cytometer and analyzed using Becton Dickinson (BD) Fluorescence-activated cell sorting (FACS) Diva Software version 6. Each marker will be expressed as median, geometric and arithmetic mean, regular and robust coefficient of variation.

Sponsors & Collaborators

• University Hospital, Grenoble

  lead OTHER

Principal Investigators

• Tatiana Raskovalova, MD · Centre Hospitalier Universitaire Grenoble Alpes, France

• Richard Veyrat-Masson, MD · Centre Hospitalier Universitaire Clermont-Ferrand, France

• Sophie Park, MD · Centre Hospitalier Universitaire Grenoble Alpes, France

• Marc Berger, MD · Centre Hospitalier Universitaire Clermont-Ferrand, France

• Jean-Yves Cesbron, MD · Centre Hospitalier Universitaire Grenoble Alpes, France

• Marie-Christine Jacob, MD · Centre Hospitalier Universitaire Grenoble Alpes, France

Eligibility

Min Age

50 Years

Sex

ALL

Healthy Volunteers

No

Timeline & Regulatory

Start

2018-02-22

Primary Completion

2018-09-06

Completion

2018-09-06

Countries

• France

Study Locations