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

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.

[Relationship between NK Cell Reconstitution and aGVHD after Allo-HSCT].

OBJECTIVE: To investigate the relationship between NK cell count/activity and acute graft-versus-host disease (aGVHD) in patients receiving allogeneic hematopoietic stem cell transplantation (allo-HSCT). METHODS: A total of 26 patients who had undergone allo-HSCT from January to July 2015 were enrolled in this study. The NK cell count/activity in the peripheral blood of recipients on day 30 after allo-HSCT were monitored by using 4-color flow cytometry. The incidence of aGVHD in patients was evaluated by clinical manifestation combinating with related pathologic indicators, and the relationship between NK cell count/activity and aGVHD were analyzed. RESULTS: In the aGVHD group and the no-aGVHD group, the NK cell count and activity on days 30 after allo-HSCT were 655±216 cells/µl vs 1169±372 cells/µl(P=0.002) and 7.3±3.6% vs 9.0±3.6% (P=0.008). In the II-IV grade aGVHD group and the 0-I grade aGVHD group, the NK cell count/activity were 617±220 cells/µl vs 1081±399 cells/µl (P=0.001) and 4.2±1.7% vs 8.3±3.5%(P=0.001). As compared with the 0-I grade aGVHD group, patients in the II-IV grade aGVHD group had higher relapse rate (57% vs 5%)(P=0.010) , lower 1-year progression-free survival(PFS) rate (43% vs 84%)(P=0.010). CONCLUSION: NK cell count/activity on day 30 after allo-HSCT were closely relates with aGVHD, which may be a potential marker for aGVHD and can provide a new target for aGVHD therapy.

[Analysis of Risk Factors for Cytomegalovirus Infection after Allogeneic Hematopoietic Stem Cell Transplantation].

OBJECTIVE: To analyze the incidence of cytomegalovirus infection and related risk factors after allogeneic hematopoietic cell transplantation and to develop a rational strategy for the preemptive treatment of CMV infection. METHODS: The clinical data of 398 patients undergoing allogeneic hematopoietic cell transplantation from December 2011 to December 2014 were analyzed retrospectively by using a Kaplan Meier analysis and Logistics model. RESULTS: Out of 398 patients 233 developed post-transplant CMV infection (58.5%). Univariate analysis showed that HLA mismatch, ATG administration, acute graft versus host disease (aGVHD), using prednisone ≥ 1 mg/kg body weight or equivalent were associated with increase of CMV infection. Multivariate analysis showed that HLA mismatch (HR = 2.765, P = 0.000), ATG administration (HR = 3.866, P = 0.000), using prednisone ≥ 1 mg/kg body weight or equivalent (HR = 4.767, P = 0.000) also were associated with increase of CMV infection. CONCLUSION: HLA mismatch, ATG administration, using prednisone ≥ 1 mg/kg are risk factors for CMV reaction.