A Retrospective Study Of Decitabine-based Regimes For Patients With Myelodysplastic Syndromes-RAEB

Purposes. To evaluate the efficacy and safety of decitabine (DAC)-based regimes in the treatment of newly diagnosed myelodysplastic syndromes-refractory anemia with excess blasts (MDS-RAEB).Patients and Methods. A total of91MDS-RAEB patients were retrospectively analyzed. All patients were divided into three groups according to treatment regimens. Among them,34patients received traditional chemotherapy (chemotherapy group),39received DAC monotherapy (DAC group) and18were treated with DAC sequentially combined with low-dose chemotherapy (combined-therapy group). Efficacy and prognosis were assessed respectively by2006International Working Group (IWG) response criteria and International Prognostic Scoring System (IPSS).Results. The complete remission (CR) rate was26.5%(9/34) in chemotherapy group,46.2%(18/39) in DAC group, and55.6%(10/18) in combined-therapy group. The median overall survival (OS) was respectively14.7months,22.4months and19.5months. Compared with chemotherapy group, the patients in combined-therapy group achieved higher CR rate (P=0.038), with significant difference in median OS (P=0.037). Particularly In patients with intermediate/poor cytogenetic abnormalities, higher CR rate (80%vs.16.7%, P=0.028) and longer OS (22.4vs.11.9months, P=0.018) were achieved in combined-therapy group compared with chemotherapy group. The median OS was prolonged in patients with MDS-RAEB2(22.4vs.15.2months, P=0.027) and IPSS Intermediate-2/high risk (19.5vs.15.2months, P=0.037). Compared with chemotherapy group, patients in DAC group achieved longer median OS (P<0.01) without significant difference in overall CR rate (P=0.082). However, in patients with age>55years and intermediate/poor cytogenetic abnormalities, CR rate (age≥55years:51.7%vs.11.8%, P<0.01; intermediate/poor cytogenetic abnormalities:62.5%vs.16.7%, P=0.023) and median OS (age≥55years:20.8vs.11.9months, P<0.01; intermediate/poor cytogenetic abnormalities:22.6vs.11.9months, P<0.01) were significantly improved. The median OS was also prolonged in patients IPSS intermediate-2/high risk (22.6vs.15.2monthes, P=0.007). Mortality at6months was respectively5.6%in combined-therapy group,0%in DAC group and16.7%in chemotherapy group, which showed a significant difference (P=0.040), and other side effects had no statistical difference.Conclusions. Compared with traditional chemotherapy, DAC sequentially combined with low-dose chemotherapy significantly improved CR rate and prolonged survival in patients with MDS-RAEB, particularly in those with intermediate/poor cytogenetic abnormalities. Combination therapy also optimized clinical responses in patients with MDS-RAEB2and with IPSS intermediate-2/high risk. With controllable side effects and low mortality rate at6months, DAC sequentially combined with low-dose chemotherapy is worth further clinical study.