[Efficacy and Safety of Allogeneic Hematopoietic Stem Cell Transplantation with Decitabine-containing Regimen in Myelodysplastic Syndromes and Myelodysplastic Syndromes Transformed Acute Myeloid Leukemia]

Abstract

Objective: To evaluate the efficacy and safety of allogeneic hematopoietic stem cell transplantation (allo-HSCT) with decitabine (Dec)-conditioning regimen in the treatment of myelodysplastic syndrome (MDS) and MDS transformed acute myeloid leukemia (MDS-AML).

Methods: The characteristics and efficacy data of 93 patients with MDS and MDS-AML who received allo-HSCT in our center from April 2013 to November 2021 were retrospectively analyzed. All patients were administered by myeloablative conditioning regimen containing Dec (25 mg/m² /d×3 d).

Results: Among the 93 patients, 63 males and 30 females, were diagnosed as MDS（n ＝77）, MDS-AML（n ＝16）. The incidence of I/II grade regimen-related toxicity (RRT) was 39.8%, and III grade RRT was only found in 1 patient (1%). Neutrophil engraftment was successful in 91 (97.8%) patients after a median neutrophil engraftment time of 14 (9-27) days; Successful platelet engraftment was achieved in 87 (93.5%) patients, with a median engraftment time of 18 (9-290) days. The incidence of acute graft versus host disease（aGVHD） and grade III-IV aGVHD was 44.2% and 16.2%, respectively. The incidence of chronic graft versus host disease（cGVHD） and moderate-to-severe cGVHD was 59.5% and 37.1%, respectively. Of the 93 patients, 54 (58%) developed posttransplant infections, among which lung infection (32.3%) and bloodstream infection (12.9%) were the most common. The median follow-up after transplantation was 45 (0.1-108) months. The 5-year overall survival (OS) rate, disease-free survival (DFS) rate, treatment-related mortality, and cumulative incidence of relapse were 72.7%, 68.4%, 25.1%, and 6.5%, respectively. And the 1-year graft-versus-host disease/relapse-free survival rate was 49.3%. The patients in different group of relative high-risk prognostic scoring or low-risk prognostic scoring, with or without poor-risk mutation(s), with mutations number ≥3 or <3 had similar 5-year OS rate (more than 70%). Multivariate analysis showed that the incidence of grade III-IV aGVHD was the independent risk factor affecting OS（P =0.008）and DFS (P =0.019).

Conclusion: Allo-HSCT with Dec-conditioning regimen is feasible and effective in the treatment of patients with MDS and MDS-AML, especially those in high prognostic risk and with poor-risk mutations.

Keywords: myelodysplastic syndrome; allogeneic hematopoietic stem cell transplantation; conditioning regimen; decitabine.