Objective: To verify the value of sister chromatid differentiation (SCD) analysis of bone marrow cells in establishing the diagnosis and predicting prognosis of myelodysplastic syndrome (MDS).
Methods: S-bromodeoxyuridine-SCD and karyotyping studies were performed in 50 cases with clinically suspected MDS.
Results: Prolonged cell cycle time (CT) was found in 33 of the 50 cases (66.0%). In 13 cases with acute myeloid leukemia (AML), all had prolonged CT. However, only 2 (10.5%) of the 19 cases with nonmalignant hematological disorders had prolonged CT. There were significant differences of CT between the cases with MDS and those with AML, aplastic anemia (AA) and benign hypercellular anemias as well as healthy individuals. However, there were no significant differences between healthy individuals and cases with AA and, with benign hepercellular anemia. CT gradually prolonged during the evolution of MDS. 24 of the 50 patients (48.0%) were found to have clonal chromosomal abnormalities. In seven cases not compatible with MDS according to FAB criteria, six were found to have clonal chromosomal abnormalities. The mortality rates were 11.8 and 50.0% in the groups of normal SCD and of prolonged SCD, respectively (P < 0.05). The rates of leukemia transformation in both the groups were 5.9% and 16.7% (P > 0.05). The median survival of both the groups was 12 months and 8 months (P = 0.051).
Conclusion: SCD analysis is valuable for establishing the diagnosis and predicting the prognosis of MDS.