Current assessment and management of measurable residual disease in patients with acute lymphoblastic leukemia in the setting of CAR-T-cell therapy / 中华医学杂志(英文版)

Chimeric antigen receptor (CAR)-modified T-cell therapy has achieved remarkable success in the treatment of acute lymphoblastic leukemia (ALL). Measurable/minimal residual disease (MRD) monitoring plays a significant role in the prognostication and management of patients undergoing CAR-T-cell therapy. Common MRD detection methods include flow cytometry (FCM), polymerase chain reaction (PCR), and next-generation sequencing (NGS), and each method has advantages and limitations. It has been well documented that MRD positivity predicts a poor prognosis and even disease relapse. Thus, how to perform prognostic evaluations, stratify risk based on MRD status, and apply MRD monitoring to guide individual therapeutic decisions have important implications in clinical practice. This review assesses the common and novel MRD assessment methods. In addition, we emphasize the critical role of MRD as a prognostic biomarker and summarize the latest studies regarding MRD-directed combination therapy with CAR-T-cell therapy and allogeneic hematopoietic stem cell transplantation (allo-HSCT), as well as other therapeutic strategies to improve treatment effect. Furthermore, this review discusses current challenges and strategies for MRD detection in the setting of disease relapse after targeted therapy.

Minimal residual disease-directed individualized therapy for hematological malignancies / 白血病·淋巴瘤

Minimal residual disease (MRD) has been used for warning of relapse and guiding the therapy selection for hematological malignancies including acute leukemia. Based on MRD-related content reported at the 64th American Society of Hematology (ASH) Annual Meeting, this article discusses the progress of MRD-directed individualized therapy for hematological malignancies with a primary focus on acute myeloid leukemia.

Intension and extension of minimal residual disease in acute leukemia / 白血病·淋巴瘤

Minimal residual disease (MRD) has been used not only for relapse prediction, prognosis re-classification and directing pre-emptive therapy of patients with acute leukemia, but also in the field of therapy for patients with other hematological malignancies or solid tumors. A deep understanding of the intension and extension of MRD is important for exploring novel methods for accurate prediction of relapse and consummating the individualized intervention strategies for malignant tumors.

More than two courses of pre-transplant consolidation therapy benefits patients with acute myeloid leukemia in the first complete remission who underwent human leukocyte antigen-matched sibling allografts: a multicenter study / 中华医学杂志(英文版)

BACKGROUND@#Although the need for consolidation chemotherapy after successful induction therapy is well established in patients with acute myeloid leukemia (AML) in first complete remission (CR1), the value of consolidation chemotherapy before allogeneic hematopoietic stem cell transplantation remains controversial.@*METHODS@#We retrospectively compared the effect of the number of pre-transplant consolidation chemotherapies on outcomes of human leukocyte antigen-matched sibling stem cell transplantation (MSDT) for patients with AML in CR1 in multicenters across China. In our study, we analyzed data of 373 AML patients in CR1 from three centers across China.@*RESULTS@#With a median follow-up of 969 days, patients with ≥ 3 courses of consolidation chemotherapy had higher probabilities of leukemia-free survival (LFS) (85.6% vs . 67.0%, P < 0.001) and overall survival (89.2% vs . 78.5%, P  = 0.007), and better cumulative incidences of relapse (10.5% vs . 19.6%, P  = 0.020) and non-relapse mortality (4.2% vs . 14.9%, P  = 0.001) than those with ≤ 2 courses of consolidation chemotherapy. Pre-transplantation minimal residual disease-negative patients with AML in CR1 who received MSDT with ≥ 3 courses of consolidation chemotherapy had a higher probability of LFS (85.9% vs . 67.7%, P  = 0.003) and a lower cumulative incidence of relapse (9.6% vs . 23.3%, P  = 0.013) than those with ≤ 2 courses.@*CONCLUSION@#Our results indicate that patients with AML in CR1 who received MSDT might benefit from pre-transplant consolidation chemotherapy.

Chimeric antigen receptor T cell immunotherapy for refractory and relapsed acute lymphoblastic leukemia: Challenge and Countermeasures / 中华检验医学杂志

Chimeric antigen receptor(CAR)-T cell immunotherapy for refractory and relapsed acute lymphoblastic leukemia (R/R ALL) is one of the breakthroughs in the field of hematological malignant disease treatment. However, several challenges remain, such as immune rejection of allogeneic CAR-T cells, leukemia relapse, as well as could we apply CAR-T cell immunotherapy to ALL patients with positive measurable residual disease and those of newly diagnosed cases. The safety and efficiency of CAR-T therapy will be further improved for patients with ALL only by establishing appropriate strategies to address these challenges.

Application of allogeneic hematopoietic stem cell transplantation in acute lymphoblastic leukemia in the era of targeted therapy / 白血病·淋巴瘤

Allogeneic hematopoietic stem cell transplantation (allo-HSCT) is one of the main curable therapies for patients with acute lymphoblastic leukemia (ALL). This article discusses the status of allo-HSCT for ALL as well as how to combine targeted therapy with allo-HSCT to improve outcomes of ALL in the era of targeted therapy based on the data obtained from the 63rd American Society of Hematology (ASH) Annual Meeting.

Positive MRD suggests a poor prognosis for ALL patients with or above CR2 before allogeneic transplantation / 中华检验医学杂志

Objective:To investigate the value of minimal residual disease (MRD) in prediction of prognosis in acute lymphoblastic leukemia (ALL) patients with or above complete remission 2 (CR2) underwent.Methods:A retrospective analysis was performed on 201 ALL patients who received allogeneic stem cell transplantation (allo-SCT) and pretransplant disease status ≥CR2 in Peking University People′s Hospital from January 2009 to December 2018. MRD was measured by multi-parameter flow cytometry at 1 month before transplantation and 1 month, 2 months, 3 months, 4 months, 6 months, 9 months or 12 months after transplantation. To investigate the influence of dynamic changes of MRD before and after transplantation on prognosis.Results:201 ALL patients, including 126 males and 75 females, with a median age of 18 years. The 3-year cumulative incidence of relapse (CIR), non-relapse mortality (NRM), leukemia-free survival (LFS) and overall survival (OS) of all cases were 34%, 16%, 50%, and 56%, respectively. Positive pre-SCT MRD patients with higher 3-year CIR (47% vs 26%, P=0.003), lower 3-year LFS (40% vs 55%, P=0.047) and OS (42% vs 60%, P=0.065) than those with negative one. Subjects with positive post-MRD had higher 3-year CIR (73% vs 22%, P<0.001) and lower 3-year LFS (28% vs 56%, P=0.005) and OS (32% vs 60%, P=0.040) compared with those with negative one. Multivariate analysis showed that both pre-MRD and post-MRD were associated with higher CIR ( HR=1.823, P=0.018; HR=3.474, P<0.001), lower LFS ( HR=1.779, P=0.007; HR=2.185, P=0.001) and OS ( HR=1.609, P=0.034; HR=1.970, P=0.001). Negative pre-and post-SCT MRD group had lower 3-year CIR (17%, 42%, 82%; P<0.001) and higher 3-year LFS (61%, 44%, 18%; P<0.001) and OS (63%, 47%, 27%; P<0.001) compared with those unrisen post-SCT MRD group, and increased post-SCT MRD group. Multivariate analysis showed that pre-and post-SCT MRD dynamics were associated with CIR, LFS and OS ( P<0.01 for all) independently. The pre-and post-SCT MRD dynamics could better distinguish CIR (C=0.669) from that of pre-SCT MRD (C=0.587) and post-SCT MRD (C=0.629). Conclusion:Our data suggest that pre-SCT MRD, post-SCT MRD and the dynamic peri-SCT MRD could be used to predict transplant outcome of ALLpatients with or above CR2 who underwent allo-SCT.

Prognostic significance of DEK-NUP214 fusion gene in patients with acute myeloid leukemia after allogeneic hematopoietic stem cell transplantation / 中华内科杂志

Objective:To investigate the dynamic change and clinical impact of DEK-NUP214 fusion gene in patients with acute myeloid leukemia (AML) receiving allogeneic hematopoietic stem cell transplantation (allo-HSCT).Methods:Real-time quantitative polymerase chain reaction (RQ-PCR) and multicolor flow cytometry (FCM) were used to detect DEK-NUP214 gene expression and leukemia-associated immunophenotype (LAIP) in 15 newly diagnosed patients with positive DEK-NUP214 and receiving allo-HSCT from September 2012 to September 2017 at Peking University People′s Hospital. The clinical outcome was analyzed using Kaplan-Meier survival curves. The impact of DEK-NUP214 expression was analyzed by log-rank test.Results:The subjects were followed-up with a median period of 657 (62-2 212) days. The median DEK-NUP214 expression level at diagnosis was 488% (274%-1 692%). Thirteen patients achieved complete remission before allo-HSCT. Thirteen patients had a residual DEK-NUP214 expression of 0.38% (0.029%-738.9%) before allo-HSCT. After allo-HSCT, DEK-NUP214 expression in 9/13 patients remained positive, which dropped by around 500 folds (5.7-5 663.0 folds) within a month post-transplant. Five patients died and 2 patients relapsed. The 3-year cumulative incidence of relapse in patients with positive DEK-NUP214 before transplant was 17.5%±11.3% and the 3-year overall survival was 60.5%±13.8%. After allo-HSCT, DEK-NUP214-negative patients had a better outcome.Conclusion:Quantitative monitor of DEK-NUP214 fusion gene could be a sensitive indicator of MRD status after allo-HSCT.

Negative effects of donor specific anti-HLA antibody on poor hematopoietic recovery in patients with hematological diseases receiving haploidentical stem cell transplantation and rituximab for desensitization / 中华内科杂志

Objective:To investigate the incidences and risk factors of poor hematopoietic reconstitution (PHR) in patients with hematological diseases who underwent haploidentical allograft and were treated with rituximab for desensitization.Methods:Eight-three donor specific anti-HLA antibody (DSA, 2000 ≤MFI<10 000) positive patients who underwent haploidentical allograft were prospectively enrolled. Rituximab (375 mg/m 2) was used for desensitization day-3 of conditioning regimen. Incidence and factors associated with PHR, including primary poor graft function and prolonged thrombocytopenia, were investigated. Results:There were 22 males and 61 females with a median age of 39(range: 1-65) years. Kaplan-Meier analysis showed that the 100 day cumulative incidences of neutrophil and platelet engraftment were 93.0% and 90.7%, respectively. The incidences of PHR were 14.7%. The 3-year relapse rate, non-relapse mortality (NRM) rate, event-free survival (EFS), leukemia-free survival (DFS) and overall survival (OS) were 6.5%, 15.1%, 70.8%, 79.4% and 79.4%, respectively. Patients with DSA MFI<5 000 (group A, n=46) experienced lower PHR (4.4% vs. 27.5%, P=0.003), and higher 3-year EFS (79.5% vs. 59.8%, P=0.020) compared to those with DSA MFI≥5 000 (group B, n=37). Multivariate analysis showed that DSA MFI≥5 000 was correlated with PHR ( HR=6.101, P=0.021). PHR was associated with higher NRM ( HR=4.110, P=0.026), lower DFS ( HR=3.656, P=0.019) and OS ( HR=3.656, P=0.019). Conclusion:Our data suggest that high pre-transplant DSA level is a risk factor for PHR in patients with hematological diseases receiving haploidentical allograft and rituximab for desensitization.

Progress on diagnosis and treatment of leukemia from the perspective of minimal residual disease / 白血病·淋巴瘤

Minimal residual disease (MRD) is one of the important variables to evaluate the outcomes of patients with leukemia, which is related to the relapse and survival of patients after treatment. This article summarizes the new progress on diagnosis and treatment of leukemia from the perspective of MRD in combination with some representative studies on MRD-based prognostic assessment and guidance on treatment options that were reported at the 62nd American Society of Hematology (ASH) Annual Meeting.

Correlation between anti-human leukocyte antigen antibodies and the outcomes of matched sibling donor transplantation in patients with hematological diseases / 白血病·淋巴瘤

Objective:To explore the relationship between anti-human leukocyte antigen (HLA) antibodies and transplant outcomes in patients with hematological diseases who underwent matched sibling donor transplantation (MSDT).Methods:A retrospective analysis was conducted in 168 patients with hematological diseases who received MSDT in Peking University People's Hospital from March 2015 to November 2017. All patients received detection of anti-HLA antibodies before transplantation, and the correlation between anti-HLA antibodies and transplant outcomes such as hematopoietic cells implantation, blood product transfusion and prognosis after transplantation were analyzed.Results:Among the 168 patients, 28 (16.7%) were positive for anti-HLA class Ⅰ or class Ⅱ antibodies, and 14 (8.3%) were positive for both anti-HLA class Ⅰ and class Ⅱ antibodies. All patients received neutrophil engraftment, 164 patients (97.9%) received platelet engraftment. Univariate analysis showed that there were no effects of anti-HLA antibodies on neutrophil engraftment and engraftment time, platelet engraftment and engraftment time, the volume of red cell transfusion, the volume of platelet transfusion, overall survival (OS) rate, disease free survival (DFS) rate and transplant-related mortality (TRM) in patients with hematological diseases underwent MSDT (all P > 0.05). Multivariate analysis showed that platelet engraftment was associated with better OS ( HR=0.065, 95% CI 0.017-0.252, P < 0.01), better DFS ( HR=0.083, 95% CI 0.024-0.289, P < 0.01) and lower TRM ( HR=0.094, 95% CI 0.014-0.626, P=0.015). Conclusion:Anti-HLA antibodies have no effect on transplant outcomes of patients with hematological diseases who have received MSDT.

Classifying AML patients with inv(16) into high-risk and low-risk relapsed patients based on peritransplantation minimal residual disease determined by CBFß/MYH11 gene expression.

Ninety acute myeloid leukemia (AML) patients with inv(16) were monitored CBFß/MYH11 transcript around allogeneic hematopoietic stem cell transplantation (allo-HSCT). A total of 23 patients received HLA-matched sibling donor transplantation (MSDT) and 67 patients received unmanipulated haploidentical hematopoietic stem cell transplantation (haplo-HSCT) were analyzed in this study. Patients were divided into four groups based on CBFß/MYH11 expression prior to transplantation (pre-MRD): with negative (group 1)/positive (group 2) pre-MRD before MSDT; with negative (group 3)/positive (group 4) pre-MRD before haplo-HSCT. The results showed that patients in group 2 had the highest cumulative incidence of relapse (2-year CIR, 40.7%), the lowest leukemia-free survival (2-year LFS, 50.8%), and overall survival (2-year OS, 62.5%). The other three groups of patients had comparable outcomes. The patients were also classified into the other three groups according to CBFß/MYH11 value of + 1 month after transplantation: group 5: pre- and post-transplant MRD were both negative; group 6: the value of post-transplant MRD was lower than 0.2%; group 7: the value of post-transplant MRD was higher than 0.2%. Group 7 had the highest CIR and the lowest LFS. These results indicated that AML patients with inv(16) were able to be separated into high-risk and low-risk relapse groups based on peritransplant MRD determined by RQ-PCR-based CBFß/MYH11. Haplo-HSCT might overcome the negative impact of pre-MRD on patient outcomes compared to MSDT.

Effects of hematological complete remission status before transplantation on outcomes of patients with B-cell acute lymphoblastic leukemia receiving haploidential stem cell transplantation / 临床检验杂志

Objective@#To investigate the association of hematological complete remssion (HCR) status on the outcomes of the patients with B-cell acute lymphoblastic leukemia (B-ALL) who were undergoing haploidentical stem cell transplantation (Haplo-SCT). @*Methods@#Retrospective analysis was performed on 317 patients with B-ALL who received Haplo-SCT with HCR before transplantation in the Institute of Hematology, Peking University from September 2012 to June 2016. A Cox proportional hazards model was used to analyze the effects of HCR status before transplantation on the outcomes of Haplo-SCT. @*Results@#The 3-year cumulative incidences of non-relapse mortality (NRM) and cumulative incidence of relapse (CIR) were 15% and 15%, respectively. The 3-year probabilities of leukemia-free survival (LFS) and overall survival (OS) were 71% and 74%, respectively. There was no statistical difference for 3-year NRM, CIR and LFS among the HCR patients with recovery of absolute neutrophil count (ANC) and platelet (CR) group, without recovery of ANC and with or without recovery of platelet (CRi) group and those in HCR with recovery of ANC but without recovery of platelet (CRp) group (P value ＞0.05 for all). The probability of OS in cases of CR group was significantly higher than that of CRi group (76% vs 59%，P=0.049). Multivariate analysis showed that factors associated with CIR included pre-transplantation minimal residual disease (P=0.006) and chronic GVHD (P=0.020). Platelet engraftment was associated with NRM, LFS, and OS (P＜0.001 for all). Grades Ⅲ-Ⅳ GVHD was associated with NRM (P＜0.001) and OS (P=0.035). Chronic GVHD was correlated with LFS (P＜0.001). @*Conclusion@#Our results indicate that no effect of HCR status before transplant on the outcomes was observed in patients with B-ALL who underwent Haplo-SCT.

Progress of relapse after allogeneic hematopoietic stem cell transplantation / 白血病·淋巴瘤

Hematologic neoplasm relapse remains one of the major causes of death after allogeneic hematopoietic stem cell transplantation (allo-HSCT). Relaspe prediction, prophylaxis and treatment after allo-HSCT are the key issues for improving the therapeutic effects and prognosis. This paper chooses some representative reports from 60th American Society of Hematology (ASH) Annual Meeting to discuss the progress of allo-HSCT.

Advances and current status of stem cell transplantation in treatment of hematological malignancies in China / 白血病·淋巴瘤

Since the founding of the People's Republic of China, much progress has been made in the field of stem cell transplantation by Chinese scholars. From the successful treatment of the first case with syngeneic bone marrow transplantation to the international original establishment of T-cell-replete haploidentical blood and marrow transplant system (known as the "Beijing Protocol"). The transformation of hematopoietic stem cell transplantation from "follow-up" to "lead-up" has been realized, and the problem of donor source has been basically solved. This article summarized the development status of stem cell transplantation in treatment of hematological malignancies in China, and the challenges that need to be addressed.

Observation on the efficacy of consolidation chemotherapy combined with allogeneic natural killer cell infusion in the treatment of low and moderate risk acute myeloid leukemia / 中华血液学杂志

Objective@#To evaluate the efficacy of consolidation chemotherapy combined with allogeneic natural killer (NK) cell infusion in the treatment of low or intermediate-risk (LIR) acute myeloid leukemia (AML) .@*Methods@#A cohort of 23 LIR AML patients at hematologic complete remission (CR) received NK cell transfusion combined with consolidation chemotherapy after 3 consolidation courses from January 2014 to June 2019 were reviewed. Control group cases were concurrent patients from Department of Hematology, and their gender, age, diagnosis, risk stratification of prognosis, CR and the number of courses of consolidate chemotherapy before NK cell transfusion were matched with LIR AML patients.@*Results@#A total of 45 times of NK cells were injected into 23 LIR AML patients during 4 to 7 courses of chemotherapy. The median NK cell infusion quantity was 7.5 (6.6-8.6) ×109/L, and the median survival rate of NK cells was 95.4% (93.9%-96.9%) . Among them, the median CD3-CD56+ cell number was 5.0 (1.4-6.4) ×109/L, accounting for 76.8% (30.8%-82.9%) ; The number of CD3+ CD56+ cells was 0.55 (0.24-1.74) ×109/L, accounting for 8.8% (4.9%-20.9%) . Before NK cell infusion, the number of patients with positive MRD in the treatment and control groups were 9/23 (39.1%) and 19/46 (41.3%) (χ2=0.030, P=0.862) respectively. After NK infusion, There was no significant difference in terms of MRD that went from negative to positive between the treatment and the control groups (14.3% vs 22.2%, χ2=0.037, P=0.847) . In the treatment group, 66.7% (6/9) of the MRD were converted from positive to negative, which was significantly higher than that in the control group (10.5%, 2/19) (χ2=6.811, P=0.009) . Morphological recurrence occurred in 1 case of MRD negative in the treatment group and 2 cases of MRD positive in the control group. By the end of follow-up, the median follow-up was 35 (10-59) months, the number of patients with morphological recurrence in the treatment group was 30.4% (7/23) , which was significantly lower than that in the control group (50.2%, 24/46) (χ2=2.929, P=0.087) , although there was no statistically significant difference between the two groups. There was no significant difference on MRD-negative between the treatment and the control groups (43.5% vs 43.5%, χ2=1.045, P=0.307) . The 3-year leukemia-free survival was better in the treatment group [ (65.1±11.1) %] than that in the control group [ (50.0±7.4) %] (P=0.047) . The 3-year overall survival in the treatment and control groups were (78.1±10.2) % and (65.8±8.0) % (P=0.212) , respectively.@*Conclusion@#The consolidation of chemotherapy combined with allogeneic NK cell infusion contributed to the further remission of patients with LMR AML and the reduction of long-term recurrence.

Everyone has a donor: contribution of the Chinese experience to global practice of haploidentical hematopoietic stem cell transplantation / 医学前沿

Human leukocyte antigen (HLA)-matched donors for hematopoietic stem cell transplantation (HSCT) have long been scarce in China. Haploidentical (haplo) donors are available for the vast majority of patients, but toxicity has limited this approach. Three new approaches for haplo-HSCT originated from Italy, China, and USA in 1990 and have been developed to world-renowned system up to now. The Chinese approach have been greatly improved by implementing new individualized conditioning regimens, donor selection based on non-HLA systems, risk-directed strategies for graft-versus-host disease and relapse, and infection management. Haplo-HSCT has exhibited similar efficacy to HLA-matched HSCT and has gradually become the predominant donor source and the first alternative donor choice for allo-HSCT in China. Registry-based analyses and multicenter studies adhering to international standards facilitated the transformation of the unique Chinese experience into an inspiration for the refinement of global practice. This review will focus on how the new era in which "everyone has a donor" will become a reality in China.

Progress of allogeneic hematopoietic stem cell transplantation / 白血病·淋巴瘤

In recent years, the indications of allogeneic hematopoietic stem cell transplantation (allo-HSCT) have been expanded due to the improvement of transplant technique. More attentions have been paid to donor specific anti-human leukocyte antigen antibodies because of the widely application of haploidentical SCT. Relapse remains a hot topic in patients with hematological malignancies who underwent allo-HSCT. Here, the progress of allo-HSCT is discussed according to some reports from 59th American Society of Hematology (ASH) Annual Meeting.

Comparison of reference values for immune recovery between event-free patients receiving haploidentical allografts and those receiving human leukocyte antigen-matched sibling donor allografts / 医学前沿

To establish optimal reference values for recovered immune cell subsets, we prospectively investigated post-transplant immune reconstitution (IR) in 144 patients who received allogeneic stem cell transplantation (allo- SCT) and without showing any of the following events: poor graft function, grades II‒IV acute graft-versus-host disease (GVHD), serious chronic GVHD, serious bacterial infection, invasive fungal infection, or relapse or death in the first year after transplantation. IR was rapid in monocytes, intermediate in lymphocytes, CD3 Tcells, CD8 T cells, and CD19 B cells, and very slow in CD4 T cells in the entire patient cohort. Immune recovery was generally faster under HLA-matched sibling donor transplantation than under haploidentical transplantation. Results suggest that patients with an IR comparable to the reference values display superior survival, and the levels of recovery in immune cells need not reach those in healthy donor in the first year after transplantation.We suggest that data from this recipient cohort should be used as reference values for post-transplant immune cell counts in patients receiving HSCT.

Clinical implication of minimal residue disease monitoring by WT1 gene detection and flow cytometry in myelodysplastic syndrome with allogeneic stem cell transplantation / 中华血液学杂志

Objective@#To investigate the clinical significance of minimal residual disease (MRD) monitoring by using WT1 gene and flow cytometry (FCM) in patients with myelodysplastic syndrome (MDS) who receiving allogeneic stem cell transplantation (allo-HSCT).@*Methods@#WT1 gene and MDS-related abnormal immunophenotype were examined by real-time quantitative polymerase chain reaction (RQ-PCR) and FCM, respectively. The bone marrow samples were collected from patients with MDS who received allo-HSCT from Feb, 2011 to Oct, 2015 in Peking University People’s Hospital before and after transplantation.@*Results@#Among 92 MDS patients, 40 (48.2%) patients were positive for WT1 (WT1+) and 9 (10.8%) patients were positive for flow cytometry (FCM+). 27 patients (29.3%) met the criteria of our combinative standard, MRDco (MRDco+). Only FCM+ post-transplant (P<0.001) and MRDco+ (P=0.017) were associated with relapse. The cumulative incidence of relapse (CIR) at 2 years were 66.7% and 1.2% (P<0.001) in FCM+ and FCM- groups. MRDco+ group had a 2-year CIR of 23.0% while MRDco- group had a 2-year CIR of 1.6% (P=0.004). The specificity of post-transplant WT1, FCM and MRDco to predict relapse was 59.0%, 96.4% and 74.7%, respectively. The sensitivity of these three MRD parameters to predict relapse was 66.7%.@*Conclusion@#Post-transplant FCM and MRDco are useful tools to monitor MRD for MDS after transplantation. The preemptive intervention based on MRDco is able to reduce the relapse rate.