Study On the Clonal Origin of Dysplastic Cells by Fluorescence in Situ Hybridization in Myelodysplastic Syndromes.

Abstract Abstract 4858 Objective To determining the clonal origin of dysplatic cells in Myelodysplastic syndromes (MDS) . Methods Karyotypic analyses of bone marrow cells using R-banding technique were carried out to determine the chromosomal abnormalities. Interphase fluorescence in situ hybridization (FISH) and morphologic analysis of bone marrow aspirates were performed in the same cells to investigate the clonal origin of dysplatic cells in 8 MDS patients. Result All patients had clonal karyotypic abnormalities: simple abnormality in 1 patient, complex abnormalities in 6 patients, coexistent of two unrelated clones in 1 patient. Most of dysplastic cells in 7 of 8 MDS patients derived from neoplasia clone while 1 patient had a reverse result,no matter what cell lineage was involved. Some of non-dysplastic cells of all patients derived from malignant clone; in 7 patients, the proportion of dysplastic cells in malignant clone were significantly higher than that of non- malignant clone. Conclusion Most of dysplastic cells in MDS derived from malignant clones, while the minority of them derived from non-malignant clones. Thus, it is reasonable to expect that in most cases myelodysplasia is present in malignant clone and can be taken as an important diagnostic evidence for MDS. Disclosures No relevant conflicts of interest to declare.