[Lower risk myelodysplastic syndrome patients with transfusion dependent treated by dose-reduced decitabine]

To evaluate the efficacy and safety of dose-reduced decitabine for the lower risk myelodysplastic syndrome (MDS) patients with transfusion dependent.

Twenty-five cases of lower risk (low or intermediate-1 risk in IPSS risk group) MDS patients with transfusion dependence from November 2009 to September 2012 were treated by dose-reduced decitabine (20 mg/m(2) intravenously once daily for 3 days). And their efficacy, side effects, quality-of-life and survival rate were evaluated.

Among them, the responses included complete remission (CR, n = 3, 12%), transfusion independence (n = 4, 16%), hematologic improvement (HI, n = 8, 32%) and stable disease (SD, n = 2, 8%). And the overall response rate (ORR) was 68% (17/25) . Among 11 cases available for cytogenetic evaluation, 1 achieved partial cytogenetic remission (PRc). IV grade hematologic toxicity rate was 48% (12/25) and III-IV grade infection rate 20% (5/25). No severe hematologic toxicity was observed. After treatment, the Karnofsky performance score (KPS) increased from 47 ± 16 to 66 ± 22 (P = 0.001); more patients were reclassified as WPSS ≤ 1 (44%vs 16%, P = 0.031) or MDACC score ≤ 7 (64% vs 8%, P = 0.022). The median follow-up time was 467(14-881) d. The 100 and 600-day expected survive rates of low and intermediate -1 risk in IPSS risk group were 100% versus 95.2% and 100% versus 90.5%.

Dose-reduced decitabine is well-tolerated and effective in transfusion dependent MDS patients in IPSS-lower risk. There is a low rate of severe hematologic toxicity and early mortality. It may prolong their survival time.