PB1995: THE USEFULNESS OF NEUTROPHIL NEW PARAMETERS ASSESSMENTS AS AN ELEMENT TO DISTINGUISH PATIENTS WITH GENETIC CHANGES IN MYELODYSPLASTIC SYNDROME - A PRELIMINARY STUDY

Topic: 9. Myelodysplastic syndromes - Biology & Translational Research Background: Myelodysplastic syndrome (MDS) is a heterogeneous group of myeloid malignancies characterized by peripheral blood cytopenias and dyshematopoiesis. MDS is often associated with cytogenetic abnormalities, gene mutations and abnormal gene expression. The specific genetic changes associated with MDS have diagnostic value influencing the selection of a new therapeutic approach for patients. The search for new, easily accessible hematological parameters confirmed by the assessment of genetic changes may be the initial differentiation of MDS patients into risk group Aims: The aim of the study was to assess the new neutrophil scattering parameters and neutrophil activation state in MDS patient with and without genetic changes. Methods: 45 patients with MDS, including 17 patients with genetic changes were examinated. Cytogenetic studies and molecular evaluation of genetic abnormalities were performed using classical cytogenetics, FISH method and PCR reaction. The assesment of neutrophil parameters was conducted using the Sysmex XN-Series hematological analyzer. The new neutrophils activation parameters: neutrophil reactivity intensity/neutrophil fluorescence intensity (NEUT-RI/NE-SFL), neutrophil granularity intensity/neutrophil complexity (NEUT-GI/NE-SSC) and neutrophil size parameters: scattering parameters (NE-FSC), width of dispersion of neutrophil complexity (NE-WX), width of dispersion of neutrophil fluorescence (NE-WY), width of dispersion of neutrophil size (NE-WZ) were performed. Three measurement signals are detected for each cell simultaneously – forward scattered light (FSC), side scattered light (SSC) and side fluorescence light (SFL). The above parameters indicate not only morphological features of neutrophils, but also cell functionality. Results: We observed higher median proportion of NE-WX, NE-WY and NE-WZ indicators in MDS patients with genetic changes than patients without genetic changes (respectively 541 vs. 410, 2266 vs. 1517 and 736 vs. 887, p< 0.05). The NE-FSC parameter was lower in MDS patients with genetic changes than patients without genetic changes (83 vs. 94, p< 0.05). Interestingly, no differences were observed for neutrophil activation parameters (NEUT-RI and NEUT-GI). Summary/Conclusion: The combination of new neutrophils parameters was found to be a new successful approach in distinguishing MDS patients with genetic changes from patients without genetic changes. It appeared that there may be unique neutrophils parameter signatures associated with an underlying mutation. In addition, the neutrophil scattering parameters generated during the leukocyte composition of bone marrow aspirate analysis as a rapid diagnostic test may provide a new tool for the prediction of MDS patients with genetic changes. Keywords: Myelodysplastic syndrome, MDS, Neutrophil