Impact of marrow blasts percentage on high-grade myelodysplastic syndrome assessed using revised international prognostic scoring system.

Clinical trials and treatment guidelines for myelodysplastic syndrome depend on several prognostic scoring systems to stratify patients by risk. These include different variables: the degree of cytopenia, percentage of bone marrow blasts, and cytogenetics. Little is known about the impact of bone marrow blasts in patients with adverse cytogenetics. In this retrospective study, we analyzed 536 patients with high-grade myelodysplastic syndrome to examine the differences in survival for patients with different percentages of bone marrow blasts. The median overall survival in patients with ≥ 5% marrow blasts was not statistically different from that for patients with < 5% marrow blasts; however, the former group had a higher risk of progression to acute myeloid leukemia (p < 0.001). Therefore, cytogenetics is the most important factor in our prognostic tools to determine survival outcomes for patients with myelodysplastic syndrome, and patients with high-risk disease have poor prognosis irrespective of their marrow blasts percentage.