Bone marrow cell cycle analysis was performed on 23 patients with myelodysplastic syndrome (MDS)[12 with refractory anemia(RA), two with RA with ringed sideroblasts(RARS), three with RA with excess blasts(RAEB), six with RAEB in transformation(RAEBt)], and 14 normal volunteers. Cells were stained with propidium iodide and analyzed by flow-cytometry. Patients with RA and RARS (low-risk MDS) showed higher rates of S-phase (21.2±4.9%) and patients with RAEB and RAEBt (high-risk MDS) showed lower rates of S-phase (9.9±5.9%) compared with normal controls (15.2±3.1%). Although the rate of S-phase decreased with disease progression, it was normalized with complete remission. An intermediate correlation (r=0.64, p<0.01) existed between the rate of S-phase and the percentage of erythroblasts in MDS. The rate of S-phase clearly reflects the severity of MDS. The high rate of S-phase in low risk MDS was concidered to be due to erythroid hyperplasia with ineffective hematopoiesis.
Cell cycle analysis