Development and Prospective Validation of a Standardized Flow Cytometric Assay of Peripheral Blood Neutrophil Myeloperoxidase Expression for Ruling Out Myelodysplastic Syndromes.
试验速览
- 阶段
- 不适用
- 状态
- 进行中（未招募）
- 发起方
- 入组人数
- 103
- 试验地点
- 1
- 主要终点
- Reference diagnosis of MDS or CMML established by bone marrow examination
研究概览
简要总结
Myelodysplastic syndromes (MDS) comprise a heterogeneous group of clonal bone marrow neoplasms that predominate in the elderly, with a median age at diagnosis of 70 years. The diagnosis of MDS relies on peripheral blood cytopenia and morphologic dysplasia for one or more hematopoietic cell lineage. Cytopenia is evidenced with hemogram while dysplasia requires bone marrow aspirate, which is an invasive procedure .
Considering the low prevalence of disease among subjects referred for suspected MDS, many patients are exposed to unnecessary bone marrow aspiration-related discomfort and harms. Therefore, an objective assay based on a peripheral blood sample that accurately discriminates MDS from other cytopenia etiologies is highly desirable.
We have previously developed and refined a flow cytometric analysis protocol for quantifying neutrophil MPO expression in peripheral blood at three university-affiliated hospitals (i.e., Clermont-Ferrand, Saint-Etienne, and Grenoble) (Raskovalova et al, Hematologica 2019). We found that the robust coefficient of variation (RCV, computed as the robust standard deviation divided by the median) within an individual subject was the best parameter in discriminating patients with versus without MDS.
Although promising, flow cytometric analysis of neutrophil MPO expression in peripheral blood is technically complex, time consuming, and not standardized. Hence, its performance requires specific expertise and the results show substantial variability. A single ready-to-use tube with lyophilized antibodies would have the potential to standardize the measurement of neutrophil MPO expression in peripheral blood across laboratories, with results available within 30-60 min in routine practice.
In this study, the investigators hypothesize that a standardized and semi-automatic flow cytometric assay of neutrophil MPO expression in peripheral blood could accurately rule out MDS and obviate the need for bone marrow aspiration and biopsy, with sensitivity and negative predictive value estimates approaching 100%.
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. A test result will have no impact on patient management. .Compliance with current guidelines disseminated by the French Haute Autorité de Santé (HAS) will be advocated for the diagnostic work-up of patients with suspected MDS. No follow-up visits are planned in this cross-sectional study.
详细描述
The primary objective of MPO-MDS-develop study is to estimate the discriminative accuracy (i.e., area under the ROC curve along with 95% CI) of a standardized and semi-automatic flow cytometric assay of neutrophil MPO expression in peripheral blood for the diagnosis of MDS in adult patients.
The secondary objectives are to assess:
- intra-laboratory reproducibility (intra- and inter-assay precision) for intra-individual RCV measurement of neutrophil MPO expression in peripheral blood;
- specimen stability for intra-individual RCV measurement of neutrophil MPO expression in peripheral blood at different time points in comparison with H0 (stored at 4°C and at room temperature);
- inter-laboratory reproducibility for intra-individual RCV measurement of neutrophil MPO expression in peripheral blood;
- the negative predictive value for intra-individual RCV measurement of neutrophil MPO expression in peripheral blood (with a prespecified threshold of 30.0%) in ruling out MDS in consecutive adult patients.
The MPO-MDS-Develop project is a multicenter, cross-sectional, diagnostic accuracy study of an index test by comparison with a reference standard, in unselected consecutive patients.
Screening: All consecutive patients referred to the immuno-hematology lab at the study sites for suspicion of MDS will be screened for eligibility. A lab physician will review inclusion and exclusion criteria, using computerized medical and laboratory records.
研究设计
- 研究类型
- Observational
- 观察模型
- Cohort
- 时间视角
- Cross Sectional
入排标准
- 年龄范围
- 18 Years 至 100 Years（Adult, Older Adult）
- 性别
- All
- 接受健康志愿者
- 否
入选标准
- •Age at enrollment ≥18 years
- •Clinical suspicion of MDS
- •Indication for bone marrow examination
- •≥1 peripheral blood cytopenia defined by hemoglobin concentration <12 g/dL for female and <13g/dL for male patients, platelet count <150 x109/L, absolute neutrophil count <1.8 x109/L
- •Inpatient and outpatient care patients
排除标准
- •Refusal to participate
- •History of or active documented MDS
- •Enrollment in intensive or critical care unit
- •Incarcerated or individuals protected by French regulation (Article L1121.5 and following, Code de la Santé Publique)
- •Not affiliated with social security system
- •Previous enrollment in the study.
结局指标
主要结局
Reference diagnosis of MDS or CMML established by bone marrow examination
时间窗: Baseline
The primary outcome is the reference diagnosis of MDS or CMML established by bone marrow examination (with Perls staining) by two independent experienced hematopathologists blinded to the index test results. Disagreements will be solved by a third hematopathologist. Bone marrow aspirate will be repeated within 4 to 6 months for patients with idiopathic cytopenia of uncertain significance (ICUS) or non-conclusive bone marrow examination.
次要结局
- Negative predictive value point estimates (along with 95% confidence interval) of neutrophil myeloperoxidase expression in peripheral blood for the diagnosis of MDS or CMML(Baseline)
- Intra-laboratory coefficient of variation for intra-individual RCV, computed as the standard deviation multiplied by 100 and divided by the mean (intra- and inter-assay precision)(Baseline)
- Relative change from baseline, expressed in percentages for intra-individual RCV(Baseline)
- Inter-laboratory coefficient of variation for intra-individual RCV(Baseline)