[Efficacy and Safety of Different Dosages of Decitabine in the Treatment of High-Risk Patients with Myelodysplastic Syndrome].

Objective: To investigate the efficacy of high-risk myelodysplastic syndrome (MDS) patients treated by different doses of decitabine (DAC) and its safety.

Methods: Thirty patients with high-risk MDS were all treated by demethylation drug DAC. According to the doses of DAC, 30 patients were divided into 10-day regimen [6 mg/(m·d)×10 d, 15 patients] group and 5-day regimen [15 mg/(m·d)×5 d, 15 patients] group. The efficacy and adverse events of the patients in the two groups were observed.

Results: The patients were followed up to May 2020, in the 10-day regimen group, 10 cases achieved complete remission (CR), 3 cases achieved partial remission (PR), and 2 cases were progressive disease (PD). Four cases died, including 1 case for heart failure, 2 cases for respiratory failure and 1 case for serious infection. In the 5-day regimen group, 11 cases achieved CR, 1 case achieved PR, 3 cases were PD. Five cases died, including 2 cases for heart failure and 3 for serious infection. The CR rate and ORR of the patients in the two groups were 66.67% vs 73.33%, 86.67% vs 80.00%, respectively, which showed no significant differences, and the efficacy also showed no significant difference. After treatment, the levels of WBC, NE, Hb and PLT of the patients in 10-day regimen group were higher than those in 5-day regimen. In the 10-day regimen group, there were 11 cases of pneumonia, 2 cases of bacteremia, 1 case of skin infection and 1 case of urinary tract infection. While in the 5-day regimen group, 13 cases of pneumonia, 5 cases bacteremia, 1 case of skin infection and 3 cases of urinary tract infection. There were 2 cases with mild gastrointestinal response in the 10-day regimen group, and 7 cases with obvious nausea and anorexia in the 5-day regimen group. The symptoms were relieved after the treatment of acid suppression, stomach protection and antiemetic. The liver, kidney and heart function were monitored. One case liver function damage and 2 cases cardiac insufficiency were observed in the 10-day regimen group. Seven cases regimen cardiac insufficiency and 4 cases regimen liver function damage were observed in the 5-day regimen group.

Conclusion: 10-day regimen and 5-day regimen are equally effective, but 10-day regimen is less myelosuppressive and more safer, which can be applied in clinical.