关键词: 骨髓增生异常综合征；白血病, 髓样, 急性；地西他滨；治疗结果

Abstract: Background　Patients with moderate to high-risk myelodysplastic syndrome（MDS） and elderly patients with acute myeloid leukemia（AML） have poor prognosis with poor tolerance of intensive conventional chemotherapy.Decitabine，a demethylated drug，may be a new promising option for them.Objective　To investigate the clinical efficacy and adverse reactions of decitabine monotherapy in the treatment of moderate-to-high-risk MDS cases and elderly cases of AML.Methods　Twenty patients （10 cases of moderate-to-high-risk MDS and 10 elderly cases of AML） who were admitted to Department of Hematology，Beijing Jishuitan Hospital from April 2016 to July 2019 were enrolled.All of them were treated with decitabine at 20 mg•（m2）-1•d-1×5 d.Follow-up was conducted once every 28 days starting from the first course of treatment till October 13，2019 or the patient's death.Routine blood test and bone marrow aspiration were performed for each follow-up.Results　Of the 20 patients，6 and 10 achieved complete response（CR） and partial response（PR），respectively，1 had stable disease（SD），1 had progressive disease（PD），and 2 died.The disease control rate was 85.0%（17/20），and the overall response rate was 80.0% （16/20）.Of the 18 elderly patients，6 and 8 achieved CR and PR，respectively，1 had SD，with a disease control rate of 83.3%（15/18），and an overall response rate of 77.8%（14/18），in particular，6 were aged over 70，but 5 of them reached CR and 1 reached SD.The rate of CR did not vary notably by diagnosis，sex，ECOG score，white blood cells，high-risk MDS，or having underlying disease（P>0.05）.There was significant difference in CR rate between those who received at least 3 courses of treatment and those did not（P<0.05）.The overall survival of 20 patients ranged from 2 to 27 months.The 1-year overall survival rate was 30.0%（6/20），and the 2-year survival rate was 20.0%（4/20）.Median progression-free survival was（14.1±3.4） months，and the median survival was（17.4±2.5） months.There were 15 cases（75.0%） of grade Ⅲ to Ⅳ myelosuppression，15 of pulmonary infection and 2 of bloodstream infection.Conclusion　Decitabine monotherapy may achieve high disease control rate in moderate-to-high-risk MDS cases and elderly cases of AML.And the main adverse reactions are myelosuppression and infection.

Key words: Myelodysplastic syndromes；Leukemia, myeloid, acute；Decitabine；Treatment outcome