Background: The myelodysplastic syndromes(MDS) are a group of acquired clonal hematopoietic disorders characterized by the peripheral cytopenias and hypercellular or normocellular dysplastic bone marrow. The event responsible for the development of MDS is generally not blown. Several recent reports have described an increased frequency of apoptosis in bone marrow cells from patients with aplastic anemia or MDS. Gersuk et al observed that Fas ligand expression was significantly increased on bone marrow cells from MDS patients as compared to normal individuals.
Methods: We examined apoptosis and Fas antigen expression using ISNEL method and immunohistochemistry on marrow cells from 36 patients with MDS.
Results: Among the 36 patients, 15 patients(42%) demonstrated apoptosis positive cells(>15%) and 9 patients(25%) demonstrated positive Fas antigen expression(>20%). The presence of apoptosis significantly correlated with hemoglobin level at diagnosis(P<0.05) and the expression of Fas antigen significantly correlated with bone marrow cellularity and CD34 positive cell aggregate group at diagnosis(P<0.05). There was no statistically significant relationship between apoptosis and Fas antigen expression. The median survival of all patients with MDS was 44 months(2-117+). Multivariate analysis showed that FAB classification and hemoglobin level at diagnosis were
significant prognostic factor but presence of apoptosis and expression of Fas antigen had no significance.
Conclusion: The data indicate that the apoptosis and expression of Fas antigen are present in patients with MDS and correlate with some clinical parameters but not
significantly associated with survival period of the patients with MDS.

Keywords: Myelodysplastic syndrome, Apoptosis, Fas antigen, Prognostic factor,