Impact of treatments before allogeneic hematopoietic stem cell transplantation in patients with higher-risk myelodysplastic syndrome

The study aimed to evaluate pre-allogeneic hematopoietic stem cell transplantation (allo-HSCT) treatment, compare the endpoints related to disease management between pre-HSCT cytoreduction patients and upfront transplantation patients with higher-risk myelodysplastic syndrome (MDS). A total of 90 higher-risk MDS patients administered allo-HSCT in the Hematology Department of the First Affiliated Hospital of Zhengzhou University were retrospectively analyzed, which included 28 patients with upfront transplantation and 62 patients with pre-transplant cytoreduction, including 30 patients received hypomethylating agents (HMA) and 32 patients received hypomethylating agents and induction chemotherapy (HMA+IC). Difference between the two groups regarding hematopoietic reconstruction, graft-versus-host disease (GVHD), relapse rate, non-relapse death (NRM), overall survival (OS) and relapse-free survival (RFS) was compared. No significant differences in OS, DFS and NRM were found between the upfront transplantation and pre-transplant cytoreduction groups, and cumulative cGVHD occurrence and relapse rates were 35.7 % and 14.5 % (P = 0.029), and 10.7 % and 12.9 % (p = 0.535), respectively. Survival rates were significantly higher in the upfront transplantation and HMA+IC groups compared with the HMA group (3-year OS: 67.9 %, 68.8 %, 43.3 %, P = 0.039; 3-year RFS: 64.3 %, 62.5 %, 43.3 %, P = 0.107; 3-year NRM: 25.0 %, 21.9 %, 50.0 %, P = 0.025). Compared with the upfront transplantation group, overall response to cytoreductive therapy (OR) and non-response to cytoreductive therapy (NR), 3-year OS were 67.9 %, 73.0 % and 32.0 % (P < 0.001), 3-year RFS were 64.3 %, 73.0 % and 24.0 % (P < 0.001) and 3-year NRM were 25.0 %, 21.6 %, and 56.0 %, respectively (P < 0.001). Upfront transplantation (n = 11) had better OS and RFS compared with the cytoreductive group (n = 10) in patients with ≥ 10 % bone marrow blast cells before transplantation (3-year OS: 63.64 %, 22.22 %, p = 0.010; 3-year DFS: 63.64 %, 20.00 %, p = 0.012, respectively). The pre-transplant treatment regimen was an independent prognostic factor of OS and NRM. If the donor is suitable, upfront transplantation may provide longer survival in higher-risk MDS patients, which, however, may also increase the incidence of cGVHD. Even in patients with bone marrow blast cells ≥ 10 % before transplantation, upfront transplantation was not worse than transplantation after cytoreductive therapy. While waiting for a transplant, HMA+IC therapy may be a good pre-transplant treatment option.