Case report: NUP98::LEDGF fusion gene drives malignant hematological tumor with mixed immunological phenotype.

This is the first report of NUP98::LEDGF positive malignant hematological tumor expressing T cell and myeloid lineage antigens. Patients carrying this fusion gene have a high relapse rate and a poor prognosis, allo-HSCT may be an option to cure this disease. This patient underwent allo-HSCT, a relapse occurred three months post-transplantation. Subsequent screening at our hospital confirmed the presence of the NUP98::LEDGF fusion gene, salvage therapy was administered, followed by a successful second allo-HSCT. Furthermore, we included eight previously reported cases from the literature for analysis and discuss.

Human leukocyte antigen evolutionary divergence as a novel risk factor for donor selection in acute lymphoblastic leukemia patients undergoing haploidentical hematopoietic stem cell transplantation.

Introduction: The human leukocyte antigen (HLA) evolutionary divergence (HED) reflects immunopeptidome diversity and has been shown to predict the response of tumors to immunotherapy. Its impact on allogeneic hematopoietic stem cell transplantation (HSCT) is controversial in different studies. Methods: In this study, we retrospectively analyzed the clinical impact of class I and II HED in 225 acute lymphoblastic leukemia patients undergoing HSCT from related haploidentical donors. The HED for recipient, donor, and donor-recipient pair was calculated based on Grantham distance, which accounts for variations in the composition, polarity, and volume of each amino acid within the peptide-binding groove of two HLA alleles. The median value of HED scores was used as a cut-off to stratify patients with high or low HED. Results: The class I HED for recipient (R_HEDclass I) showed the strongest association with cumulative incidence of relapse (12.2 vs. 25.0%, P = 0.00814) but not with acute graft-versus-host disease. The patients with high class II HED for donor-recipient (D/R_HEDclass II) showed a significantly higher cumulative incidence of severe aGVHD than those with low D/R_HEDclass II (24.0% vs. 6.1%, P = 0.0027). Multivariate analysis indicated that a high D/R_HEDclass II was an independent risk factor for the development of severe aGVHD (P = 0.007), and a high R_HEDclass I had a more than two-fold reduced risk of relapse (P = 0.028). However, there was no discernible difference in overall survival (OS) or disease-free survival (DFS) for patients with high or low HED, which was inconsistent with the previous investigation. Discussion: While the observation are limited by the presented single center retrospective cohort, the results show that HED has poor prognostic value in OS or DFS, as well as the associations with relapse and aGVHD. In haploidentical setting, class II HED for donor-recipient pair (D/R_HEDclass II) is an independent and novel risk factor for finding the best haploidentical donor, which could potentially influence clinical practice if verified in larger cohorts.

A safety and efficacy study of allogeneic haematopoietic stem cell transplantation for refractory and relapsed T-cell acute lymphoblastic leukaemia/lymphoblastic lymphoma patients who achieved complete remission after autologous CD7 chimeric antigen receptor T-cell therapy.

CD7-targeted chimeric antigen receptor T-cell (CAR-T) therapy has shown promising initial complete remission (CR) rates in patients with refractory or relapsed (r/r) T-cell acute lymphoblastic leukaemia and lymphoblastic lymphoma (T-ALL/LBL). To enhance the remission duration, consolidation with allogeneic haematopoietic stem cell transplantation (allo-HSCT) is considered. Our study delved into the outcomes of 34 patients with r/r T-ALL/LBL who underwent allo-HSCT after achieving CR with autologous CD7 CAR-T therapy. These were compared with 124 consecutive T-ALL/LBL patients who received allo-HSCT in CR following chemotherapy. The study revealed that both the CAR-T and chemotherapy cohorts exhibited comparable 2-year overall survival (OS) (61.9% [95% CI, 44.1-78.1] vs. 67.6% [95% CI, 57.5-76.9], p = 0.210), leukaemia-free survival (LFS) (62.3% [95% CI, 44.6-78.4] vs. 62.0% [95% CI, 51.8-71.7], p = 0.548), non-relapse mortality (NRM) rates (32.0% [95% CI, 19.0-54.0] vs. 25.3% [95% CI, 17.9-35.8], p = 0.288) and relapse incidence rates (8.8% [95% CI, 3.0-26.0] vs. 15.8% [95% CI, 9.8-25.2], p = 0.557). Patients aged ≤14 in the CD7 CAR-T group achieved high 2-year OS and LFS rates of 87.5%. Our study indicates that CD7 CAR-T therapy followed by allo-HSCT is not only effective and safe for r/r T-ALL/LBL patients but also on par with the outcomes of those achieving CR through chemotherapy, without increasing NRM.

Characteristics and literature review of ETV6::ABL1 fusion gene-positive acute myeloid leukemia.

OBJECTIVE: To describe the features of ETV6::ABL1 AML as well as the clinical treatment and outcomes. METHODS: Clinical data were collected from three patients diagnosed with ETV6::ABL1 AML at Hebei Yanda Lu Daopei Hospital and Beijing Lu Daopei Hospital. Their clinical and laboratory features were analyzed, and the treatment process and outcomes were described. Ten reported cases of ETV6::ABL1 AML from the literature were also included for analysis. RESULTS: The median age of the patients was 34 years, and 2 patients were male. No patient had a history of blood disorders before diagnosis. After relapse, they were referred to our hospital, where the ETV6::ABL1 gene was detected. Unfortunately, Patient 1 died rapidly after leukemia relapse due to severe infection. Patients 2 and 3 received salvage therapy with a dasatinib-containing regimen, followed by allo-HSCT, and are currently alive and disease-free. CONCLUSION: ETV6::ABL1 is a rare but recurrent genetic aberration in AML, and the combined use of fluorescence in situ hybridization and PCR can better identify this fusion gene. Patients carrying ETV6::ABL1 have a high relapse rate and a poor prognosis. TKIs are a reasonable treatment option for this group, and allo-HSCT may be curative.

Analysis benefits of a second Allo-HSCT after CAR-T cell therapy in patients with relapsed/refractory B-cell acute lymphoblastic leukemia who relapsed after transplant.

Background: Chimeric antigen receptor (CAR) T-cell therapy has demonstrated high initial complete remission (CR) rates in B-cell acute lymphoblastic leukemia (B-ALL) patients, including those who relapsed after transplant. However, the duration of remission requires improvements. Whether bridging to a second allogeneic hematopoietic stem cell transplant (allo-HSCT) after CAR-T therapy can improve long-term survival remains controversial. We retrospectively analyzed long-term follow-up data of B-ALL patients who relapsed post-transplant and received CAR-T therapy followed by consolidation second allo-HSCT to investigate whether such a treatment sequence could improve long-term survival. Methods: A single-center, retrospective study was performed between October 2017 and March 2022, involving 95 patients who received a consolidation second transplant after achieving CR from CAR-T therapy. Results: The median age of patients was 22.8 years (range: 3.3-52.8) at the second transplant. After the first transplant, 71 patients (74.7%) experienced bone marrow relapse, 16 patients (16.8%) had extramedullary relapse, 5 patients (5.3%) had both bone marrow and extramedullary relapse and 3/95 patients (3.2%) had positive minimal residual disease (MRD) only. Patients received autologous (n=57, 60.0%) or allogeneic (n=28, 29.5%) CAR-T cells, while 10 patients (10.5%) were unknown. All patients achieved CR after CAR-T therapy. Before second HSCT, 86 patients (90.5%) were MRD-negative, and 9 (9.5%) were MRD-positive. All second transplant donors were different from the first transplant donors. The median follow-up time was 623 days (range: 33-1901) after the second HSCT. The 3-year overall survival (OS) and leukemia-free survival (LFS) were 55.3% (95%CI, 44.3-66.1%) and 49.8% (95%CI, 38.7-60.9%), respectively. The 3-year relapse incidence (RI) and non-relapse mortality (NRM) were 10.5% (95%CI, 5.6-19.6%) and 43.6% (95%CI, 33.9-56.2%), respectively. In multivariate analysis, the interval from CAR-T to second HSCT ≤90 days was associated with superior LFS(HR, 4.10, 95%CI,1.64-10.24; p=0.003) and OS(HR, 2.67, 95%CI, 1.24-5.74, p=0.012), as well as reduced NRM (HR, 2.45, 95%CI, 1.14-5.24, p=0.021). Conclusions: Our study indicated that CAR-T therapy followed by consolidation second transplant could significantly improve long-term survival in B-ALL patients who relapsed post-transplant. The second transplant should be considered in suitable patients and is recommended to be performed within 90 days after CAR-T treatment.

Addition of venetoclax to myeloablative conditioning regimens for allogeneic hematopoietic stem cell transplantation in high-risk AML.

BACKGROUND: Venetoclax monotherapy is an effective option for patients with acute myeloid leukemia (AML). Venetoclax has also been used in non-myeloablative conditioning allogeneic hematopoietic stem cell transplantation (allo-HSCT) for high-risk AML with a tolerable toxicity profile. However, the efficacy and safety of a venetoclax-containing myeloablative conditioning (MAC) allo-HSCT regimen for high-risk AML have not been evaluated. OBJECTIVE: To evaluate the safety and efficacy of a MAC regimen containing venetoclax for high-risk AML. STUDY DESIGN: From 25 February 2021 to 4 September 2022, a total of 31 patients with high-risk AML who underwent allo-HSCT and a MAC regimen with venetoclax were analyzed. RESULTS: At the time of transplantation, 21 patients were in first complete remission (CR1), 4 were in a second complete remission (CR2), and 6 in non-remission (NR). Twenty-four patients (77.4%) were minimal residual disease (MRD)-positive before transplant. The FLT3-ITD gene mutation was present in 51.6% of patients. NUP98 rearrangement, MLL rearrangement or MLL-PTD and DEK::CAN fusion genes were found in 5 (16.1%), 7(22.6%) and 2 (6.5%) patients, respectively. Twenty-nine (93.6%) patients underwent haploidentical allo-HSCT. The median follow-up time was 278 days (range: 52-632 days). The 100-day cumulative incidence of grade 3 to 4 acute graft-versus-host disease (aGVHD) was 16.1% (95%CI, 7.2-36.0%). The 180-day cumulative incidence of moderate to severe chronic graft-versus-host disease (cGVHD) was 7.1% (95%CI, 1.9-26.9%). Cumulative incidence of 100-day cytomegalovirus (CMV) viraemia and 100-day Epstein-Barr virus (EBV) viraemia was 61.6% (95%CI, 46.5-81.4%) and 3.2% (95%CI, 0.4-22.2%), respectively. The 600-day overall survival (OS) and leukemia-free survival (LFS) were 80.9% (95%CI, 63.5-93.6%) and 81.3% (95%CI, 64.2-93.7%), respectively. The 600-day relapse incidence (RI) and non-relapse mortality (NRM) was 6.9% (95%CI, 1.8-26.3%) and 11.7% (95%CI, 3.9-35.0%). CONCLUSION: Our study shows that the addition of venetoclax to a MAC allo-HSCT was feasible, safe and effective for high-risk AML patients.

Comparisons of unmanipulated haploidentical donor, unrelated cord blood donor and matched unrelated donor hematopoietic stem cell transplantation in pediatric acquired severe aplastic anemia: a single center study.

We retrospectively analyzed the outcomes of 240 pediatric SAA patients who underwent unmanipulated alternative HSCT between September 2012 and November 2020 at our center. The incidence of GF (PGF + SGF) was higher in the UCBD cohort compared to the MUD and HID cohorts [(13.5% ± 6.5%) vs (0%), and (1.6% ± 5.3%), respectively, p = .0001]. The incidence of platelet engraftment within 180 days post-HSCT was lower in the UCBD cohort (82.4% ± 2.3%) compared to the HID group (96.2% ± 1.3%) and the MUD group (97.4% ± 0.5%) (p = .020). the median duration time for platelet engraftment in the UCBD cohort was 29 days, longer than in HID cohort 14 days and the MUD cohort 13 days (p = .005). UCBD cohort had a lower 3-year failure-free survival (FFS) (70.5% ± 8.4%) compared to the HID cohort (81.1% ± 4.3%) and the MUD cohort (92.5% ± 3.1%) (p = .030) and lower 3-year GVHD/relapse free survival (GRFS) (63.3% ± 9.5.4%) compared to the HID cohort (75.5% ± 6.8%) and MUD cohort (87.9% ± 4.5%) (p = .002). UCBD-HSCT had inferior FFS and GRFS compared to an HSCT with an HID or MUD in pediatric patients with acquired SAA. A UCBD-HSCT had a higher GF and lower incidence of platelet engraftment and longer platelet engraftment time.

Efficacy and safety of CD19 CAR-T cell therapy for acute lymphoblastic leukemia patients relapsed after allogeneic hematopoietic stem cell transplantation.

Allogeneic hematopoietic stem cell transplantation (allo-HSCT) is an effective therapy for B-cell acute lymphoblastic leukemia (B-ALL). Although allo-HSCT can be curative for some B-ALL patients, relapse still occurs in some patients following allo-HSCT. Conventional chemotherapies show poor efficacy in B-ALL patients who have relapsed following allo-HSCT. In the past decade, chimeric antigen receptor T-cell (CAR-T) therapy has shown to be efficacious for B-ALL patients. In particular, autologous CD19 CAR-T therapy results in a high remission rate. However, there are challenges in the use of CD19 CAR-T therapy for B-ALL patients who have relapsed following allo-HSCT, including the selection of CAR-T cell source for manufacturing, post-CAR-T graft-versus-host disease (GVHD) risk, maintenance of long-term efficacy after remission through CAR-T therapy, and whether a consolidative second transplant is needed. In this review, we describe the current status of CAR-T therapy for B-ALL patients who have relapsed following allo-HSCT, the advantages and disadvantages of various CAR-T cell sources, the characteristics and management of GVHD following CAR-T therapy, and the risk factors that may affect long-term efficacy.

[A Single-Center Analysis of the Use of G-CSF Combined with Plerixafor to Mobilize Peripheral Blood Hematopoietic Stem Cell from Healthy Related Donors in Allogeneic Hematopoietic Stem Cell Transplantation].

OBJECTIVE: To study the effect and safety of G-CSF combined with Plerixafor on the mobilization of peripheral blood hematopoietic stem cells from healthy related donors of allogeneic hematopoietic stem cell transplantation (allo-HSCT). METHODS: It was analyzed retrospectively that the data of peripheral blood hematopoietic stem cells from 33 (observation group) related donors mobilized by G-CSF plus Plerixafor in Hebei Yanda Lu Daopei Hospital from April 2019 to April 2021. Bone marrow and peripheral blood hematopoietic stem cells (PBSCs) of these donors were respectively collected on the fourth and fifth day of G-CSF-induced mobilization. Following the administration of Plerixafor on the night of the fifth day, PBSCs were collected on the sixth day once again. 46 donors using "G-CSF only" mobilization method in the same period were randomly selected as the control and respectively analyzed the differences of CD34+ cell counts on the fifth and the sixth day in two groups. And the donors' adverse reaction to Plerixafor in the form of questionnaire was also observed. Then it was compared that the patients who underwent allo-HSCT in "G-CSF+Plerixafor" group and "G-CSF only" group in terms of acute GVHD at grade I-IV or III-IV, CMV reactivation and EBV reactivation. RESULTS: CD34+ cells count (M±Q) among PBSCs collected on the fifth and the sixth day in the observation group were (1.71±1.02)×106/kg and (4.23±2.33)×106/kg, respectively. CD34+ cell counts on the sixth day was significantly higher than that of the fifth day (P<0.001); While the counterparts in the control group were (2.47±1.60)×106/kg and (1.87±1.37)×106/kg, respectively. By statistical analysis, CD34+ cell counts on the sixth day was significantly less than that of the fifth day (P<0.001). The adverse reaction to Plerixafor for the donors in the study were all grade 1 or 2 (mild or moderate) according to CTCAE 5.0 and disappeared in a short time. The patients who underwent allo-HSCT in the "G-CSF+Plerixafor" group and "G-CSF only" group were not statistically significant in terms of acute GVHD at grade I-IV or III-IV, CMV reactivation and EBV reactivation (P>0.1). CONCLUSION: The cell mobilization program of G-CSF combined with Plerixafor is safe and effective for being applied to allo-HSCT. The addition of Plerixafor can significantly increase the number of CD34 postive cells in the PBSC collection. Key words　　; ;

Prognostic factors of second hematopoietic allogeneic stem cell transplantation among hematological malignancy patients relapsed after first hematopoietic stem cell transplantation: A single center study.

Introduction: We aimed to evaluate prognostic factors of a second allogeneic stem cell transplantation (allo-HSCT2) among hematological malignancy patients who have relapsed after the first allo-HSCT(allo-HSCT1). Methods: We retrospectively analyzed 199 hematological malignancy patients who received allo-HSCT2 as a salvage treatment post allo-HSCT1 relapse between November 2012 and October 2021. Results: The median age at allo-HSCT2 was 23 (range: 3-60) years. The median time to relapse after HSCT1 was 9 (range: 1-72) months. Prior to allo-HSCT2, patients had the following hematopoietic cell transplantation-comorbidity indexes (HCT-CI): 127 with a score of 0, 52 with a score of 1, and 20 with a score of 2 or greater. Fifty percent of patients received chimeric antigen receptor (CAR) T-cell therapy following HSCT1 relapse. Disease status was minimal residual disease (MRD)-negative complete remission (CR) among 119 patients, MRD-positive CR among 37 patients and non-remission (NR) for 43 patients prior to allo-HSCT2. Allo-HSCT2 was performed from a new donor in 194 patients (97.4%) and 134 patients (67.3%) received a graft with a new mismatched haplotype. The median follow-up time was 24 months (range: 6-98 months), and the 2-year OS and LFS were 43.8% ± 4.0% and 42.1% ± 4.1%, respectively. The 2-year cumulative incidence of relapse (CIR) and non-relapse mortality (NRM) was 30.0%±4.8% and 38.5%±3.8%, respectively. Cox regression multivariate analysis showed that disease statusof MRD-negative CR, HCT-CI score of 0 prior to allo-HSCT2, and new mismatched haplotype donor were predictive factors of improved OS and LFS compared to patients without these characteristics. Based on these three favorable factors, we developed a predictive scoring system for patients who received allo-HSCT2. Patients with a prognostic score of 3 who had the three factors showed a superior 2-year OS of 63.3% ± 6.7% and LFS of 63.3% ± 6.7% and a lower CIR of 5.5% ± 3.1% than patients with a prognostic score of 0. Allo-HSCT2 is feasible and patients with good prognostic features prior to allo-HSCT2 -disease status of CR/MRD- and HCT-CI score of 0 as well as a second donor with a new mismatched haplotype could have the maximal benefit from the second allo-HSCT. Conclusions: Allo-HSCT2 is feasible and patients with good prognostic features prior to allo-HSCT2 -disease status of CR/MRD- and HCT-CI score of 0 as well as a second donor with a new mismatched haplotype could have the maximal benefit from the second allo-HSCT.

Unmanipulated haploidentical donor and matched unrelated donor hematopoietic stem cell transplantation in patients with paroxysmal nocturnal hemoglobinuria: a single-center study.

We analyzed the outcomes of 32 patients with paroxysmal nocturnal hemoglobinuria (PNH) who underwent either a haploidentical donor (HID) or a matched unrelated donor (MUD) hematopoietic stem cell transplantation (HSCT). Seventeen patients received an HSCT from an HID and 15 patients received an HSCT from an MUD. The median follow-up time of the surviving patients was 36 months (range: 12-96 months). No significant differences were observed in the 3-year overall survival (OS) between the HID and MUD cohorts (74.1%±11.4% vs. 93.3%±6.4%, respectively, p=.222) or in the 3-year failure-free survival (68.8%±11.8% vs. 86.7%±8.8%, respectively, p=.307). Treatment-related mortality occurred in five patients. A univariate analysis of risk factors revealed platelet engraftment failure negatively impacted OS and FFS. We conclude that HID and MUD-HSCT are feasible and can be effective options for those PNH patients with concomitant bone marrow failure, recurrent life-threatening thrombosis, and uncontrollable hemolysis.

Integrating CAR T-Cell Therapy and Transplantation: Comparisons of Safety and Long-Term Efficacy of Allogeneic Hematopoietic Stem Cell Transplantation After CAR T-Cell or Chemotherapy-Based Complete Remission in B-Cell Acute Lymphoblastic Leukemia.

Patients often undergo consolidation allogeneic hematopoietic stem cell transplantation (allo-HSCT) to maintain long-term remission following chimeric antigen receptor (CAR) T-cell therapy. Comparisons of safety and efficacy of allo-HSCT following complete remission (CR) achieved by CAR-T therapy versus by chemotherapy for B-cell acute lymphoblastic leukemia (B-ALL) has not been reported. We performed a parallel comparison of transplant outcomes in 105 consecutive B-ALL patients who received allo-HSCT after achieving CR with CAR-T therapy (n=27) or with chemotherapy (n=78). The CAR-T-allo-HSCT group had more patients in second CR compared to the chemotherapy-allo-HSCT group (78% vs. 37%; p<0.01) and more with complex cytogenetics (44% vs. 6%; p<0.001) but the proportion of patients with pre-transplant minimal residual disease (MRD) was similar. The median follow-up time was 49 months (range: 25-54 months). The CAR-T cohort had a higher incidence of Grade II-IV acute graft-versus-host disease (aGVHD 48.1% [95% CI: 46.1-50.1%] vs. 25.6% [95%CI: 25.2-26.0%]; p=0.016). The incidence of Grade III-IV aGVHD was similar in both groups (11.1% vs.11.5%, p=0.945). The overall incidence of chronic GVHD in the CAR-T group was higher compared to the chemotherapy group (73.3% [95%CI: 71.3-75.3%] vs. 55.0% [95%CI: 54.2-55.8%], p=0.107), but the rate of extensive chronic GVHD was similar (11.1% vs.11.9%, p=0.964). Efficacy measures 4 years following transplant were all similar in the CAR-T vs. the chemotherapy groups: cumulative incidences of relapse (CIR; 11.1% vs.12.8%; p=0.84), cumulative incidences of non-relapse mortality (NRM; 18.7% vs. 23.1%; p=0.641) leukemia-free survival (LFS; 70.2% vs. 64.1%; p=0.63) and overall survival (OS; 70.2% vs. 65.4%; p=0.681). We found that pre-transplant MRD-negative CR predicted a lower CIR and a higher LFS compared with MRD-positive CR. In conclusion, our data indicate that, in B-ALL patients, similar clinical safety outcomes could be achieved with either CD19 CAR T-cell therapy followed by allo-HSCT or chemotherapy followed by allo-HSCT. Despite the inclusion of more patients with advanced diseases in the CAR-T group, the 4-year LFS and OS achieved with CAR T-cells followed by allo-HSCT were as remarkable as those achieved with chemotherapy followed by allo-HSCT. Further confirmation of these results requires larger, randomized clinical trials.

Hematopoietic stem cell transplantation for inherited bone marrow failure syndromes: alternative donor and disease-specific conditioning regimen with unmanipulated grafts.

Objective: The outcomes of alternative donor hematopoietic stem cell transplantation (HSCT) with unmanipulated grafts for Inherited bone marrow failure syndromes (IBMFS) are discouraging. Our study is to demonstrate that IBMFS with disease-specific characteristics requires a tailored conditioning regimens to enhance engraftment and reduce regimen related toxicities. Methods: We retrospectively analyzed 42 patients diagnosed with IBMFS and transplanted with an alternative donor graft at our center from November 2012 to August 2018. Twenty-seven patients had Fanconi anemia (FA), 7 had dyskeratosis congenita (DC), and 8 had severe congenital neutropenia (SCN). Patients received ex-vivo unmanipulated alternative donor grafts from a matched unrelated donor (MUD) (n = 22), haploidentical donor (HID) (n = 17) and unrelated cord blood donor (UCBD) (n = 3). FA and DC patient subgroups received reduce intensified conditioning (RIC), while SCN patients received a myeloablative conditioning (MAC) regimen. Results: The median follow-up time for the surviving patients was 38 months (range: 9-63 months). The failure-free survival (FFS) for entire cohort was 76.1%, and was 72.4%, 100% and 56.2% for patients with FA, DC and SCN, respectively. There were no primary graft failures. The cumulative incidence of aGVHD at day 100 was 48.1%. The cumulative incidence of cGVHD at 1 and 3 years was 35.0% and 69.3%, respectively. Conclusion: HSCT using alternative donors with unmanipulated grafts and disease-specific conditioning regimens for IBMFS patients shows promising survival.

Comparable outcomes among unmanipulated haploidentical, matched unrelated, and matched sibling donors in BU-based myeloablative hematopoietic stem cell transplantation for intermediate and adverse risk acute myeloid leukemia in complete remission: a single-center study.

There are a limited number of studies comparing outcomes of busulfan (BU)-based myeloablative hematopoietic stem cell transplantation using unmanipulated haploidentical donors (HIDs), HLA-matched unrelated donors (MUDs), and HLA-matched sibling related donors (MSDs) in acute myeloid leukemia (AML) patients with complete remission (CR) status. With this background, we compared outcomes among 377 cases of CR following consecutive HID-HSCT for AML (CR) to 86 MUD and 92 MSD-HSCT cases. All patients received BU-based myeloablative conditioning and an unmanipulated graft within the same period. The median patient age was 23 years (range 1.1 to 65 years), and 230 patients (41.4%) were under age18. Among the 555 patients, 432 (77.8%) were of intermediate cytogenetic risk and 123 (22.2%) were of adverse risk. A total of 113 patients (20.5%) had FLT3-ITD+ AML, 425 patients (76.6%) were in first complete remission (CR1) post-transplant, and 130 (23.4%) patients were in second CR (CR2). GVHD prophylaxis included mycophenolate mofetil (MMF), cyclosporine-A (CSA) with short-term methotrexate (MTX) for HID, and MUD-HSCT. MMF is not used for MSD-HSCT. The median survival follow-up time was 42 months (range 18-91 months). The 3-year leukemia-free survival (LFS) among the HID, MUD, and MSD cohorts was 73.8% ± 4.8%, 66.4% ± 8.5%, 74.5% ± 2.4%, respectively (P = 0.637). Three-year overall survival (OS) was 74.9% ± 2.4%, 81.8% ± 4.3%, and 77.5% ± 4.5% among the HID, MUD, and MSD cohorts, respectively (P = 0.322). There were no difference among the relapse rate among the HID, MUD, and MSD donor cohorts (14.3% ± 4.0% vs 20.3% ± 6.4% vs 14.5% ± 2.2, respectively; P = 0.851) or the non-relapse mortality (NRM) (12.3% ± 3.5% vs 9.5% ± 3.2% vs 14.0% ± 1.8%, respectively; P = 0.441). Multivariate analyses showed that MRD-positive pre-HSCT was the only risk factor associated with a lower OS and LFS and higher risk of relapse among all 555 patients. Compared with the use of a MUD or MSD, an HID for HSCT had similar outcomes among AML patients with CR states who underwent an allo-HSCT with BU-based myeloablative conditioning. MFC-MRD-positive pre-HSCT was an independent negative factor impact on outcomes for AML patients in CR. We conclude that for AML patients who do not have a MSD or if an urgent transplant is required, HSCT from an HID is a valid option.

Unmanipulated haplo-identical donor transplantation compared with identical sibling donor had better anti-leukemia effect for refractory/relapsed acute myeloid leukemia not in remission status.

Prior studies have suggested that for leukemia patients with high-risk features, haplo-identical-hematopoietic stem cell transplantation (HID-HSCT) has a stronger anti-leukemia effect compared with HSCT using an identical sibling donor (ISD-HSCT). However, it is unclear whether an HID-HSC transplant also augments the graft-versus-leukemia (GVL) effect among refractory/relapsed (R/R) acute myeloid leukemia (AML) patients who are not in remission (NR). We conducted a retrospective analysis of 124 R/R AML patients with NR status who underwent HID-HSCT between April 2012 and December 2016 and compared these to 27 R/R AML patients who underwent an ISD-HSCT within the same timeframe. Among all of the patients, 68 (45.0%) had primary induction failure (PIF) and 83 (54.9%) were relapsed and had failed to respond to at least one cycle of salvage combination chemotherapy. Myeloablative conditioning regimens were administered to all patients. Here, we present a retrospective multivariate analysis of pre-transplantation risk factors and characteristics of all 151 patients and developed a predictive scoring system to predict patient survival. The median period of follow-up was 46 months for all patients. The HID cohort had a higher 5-year overall survival (OS) compared with the ISD cohort (48.6% ± 4.6% vs 25.9% ± 8.4, respectively; P = 0.017) and higher LFS (leukemia-free survival) (41.6% ± 7.5% vs 25.9% ± 8.4%, respectively; P = 0.019). There was no difference in the 5-year cumulative incidence of non-relapse mortality (NRM) (18.0% ± 3.8% and 34.9% ± 12.6%, respectively; P = 0.212) between the two group. However, the 5-year cumulative incidence of relapse (CIRs) was lower in the HID group compared with the ISD group (55.4% ± 8.9% vs 67.3% ± 9.9%, respectively; P = 0.021). Multivariate analysis showed three risk factors associated with OS and LFS: (1) ISD-HSCT, (2) use of a standardized conditioning regimen, and (3) less than 50% proportional reduction of blast cells in the bone marrow (BM). Based on these three risk factors, we developed a predictive scoring system for R/R AML patients undergoing HSCT. Patients who had a predictive score of 0 and 1 had a 66.6% ± 4.5% and 44.1% ± 3.6% OS rate at 5 years, respectively. Patients with a score ≥ 2 had only a 4.4 ± 0.2% OS rate at 5 years. An HID-HSCT had a better anti-leukemia effect among R/R AML patients with an NR status compared with an ISD-HSCT. We also identified pre-transplantation risk factors to delineate subgroups that could derive maximal benefit from HSCT.

Unmanipulated Haploidentical Hematopoietic Stem Cell Transplantation Achieved Outcomes Comparable With Matched Unrelated Donor Transplantation in Young Acquired Severe Aplastic Anemia.

Salvage haploidentical hematopoietic stem cell transplantation (haplo-HSCT) is considered in patients with severe aplastic anemia (SAA) if a matched unrelated donor (MUD) is unavailable. However, studies on haplo- and MUD transplantation in SAA are lacking. The present study retrospectively analyzed the outcomes of 89 young SAA patients who underwent unmanipulated alternative HSCT between September 2012 and September 2016 at our single center. Forty-one patients received haploidentical donors and forty-eight patients MUDs for HSCT. Most were heavily transfused and refractory to previous immunotherapy. The median durations for myeloid engraftment in the haplo- and MUD cohorts were 14 (range, 10 to 21) and 13 (range, 10 to 18) days, respectively. Compared with the MUD cohort, haplo-HSCT cohorts had an increased cumulative incidence of acute graft-versus-host disease (GVHD) grades II to IV (43.9% ± 7.8% versus 12.5% ± 4.8%, P = .001) and grades III to IV (21.1% ± 6.7% versus 6.6% ± 3.7%, P = .045) and similar limited chronic GVHD (47.7% ± 8.5% versus 38.5% ± 7.3%, P = .129) and extensive chronic GVHD (12.1% ± 6.8% versus 9.1% ± 4.3%, P = .198). The median follow-up time of the surviving patients was 26 months (range, 6 to 45). No significant differences were observed between haplo-HSCT and MUD HSCT cohorts in 3-year overall survival (80.3% ± 5.1% versus 89.6% ± 7.0%, P = .210), disease-free survival (76.4% ± 5.1% versus 89.4% ± 7.7%, P = .127), and GVHD-free failure-free survival (79.0% ± 8.6% versus 71.6% ± 9.3%, P = .976). Thus, haplo-HSCT, as salvage therapy, achieved similar outcomes as MUD HSCT in young SAA patients, thereby rendering it as an effective and safe option for SAA.

[Salvaged allogeneic hematopoietic stem cell transplantation for refractory/recurrent acute myeloid leukemia].

OBJECTIVE: To evaluate the efficacy of salvaged allogeneic hematopoietic stem cell transplantation (allo-HSCT) for refractory/recurrent acute myeloid leukemia (AML). METHODS: A total of 45 patients with refractory/recurrent AML were enrolled from September 2006 to April 2010. The median blasts in bone marrow (BM) were 36% (20% to 92%) before conditioning. The donors were identical siblings (6) or unrelated ones (9) or haploidentical family members (30). Conditioning regiments were individualized according to patients' status, the regimen with high-dose cytarabine plus BuCy/CY was mostly used (20). The patients with impaired organ function received above regimen except using fludarabine instead of cyclophosphamide (16). FLAG followed by reduced-intensified BuCy was employed for the recipients with more than 40% blasts in BM (6) to reduce leukemia burden. TBI/CY or TBI/Fludarabine was used for the recipients with extramedullary infiltration of leukemia or multidrug resistant leukemia. G-CSF, MTX, NVT, Vm26, Acla or Thaltipa was added into conditioning regiments according to leukemia character. RESULTS: All but 2 patients attained durable engraftment. The incidence of grade II to IV aGVHD and cGVHD were 34%, 59.1%, respectively. With median follow-up 30 (0.5 - 57) months, the relapse rate was 29.2%. Twenty-nine of 45 (60.2%) patients remained in complete remission since salvaged HSCT. Three-years disease-free survival and overall survival were 60.2% and 62.6%, respectively. CONCLUSION: Our results indicated that the combination of salvaged HSCT with prophylactic immunotherapy might be a promising modality for treatment of refractory/recurrent AML, even with high leukemia burden.

[Monitoring of early Epstein-Barr virus reactivation and preemptive therapy after allogeneic hematopoietic stem cell transplantation].

OBJECTIVE: To investigate early Epstein-Barr virus (EBV) reactivation and the outcome of preemptive therapy after allogeneic hematopoietic stem cell transplantation (allo-HSCT). METHODS: From January 2007 to January 2009, totally 277 patients after allo-HSCT were studied (haploidentical 116, unrelated 75, matched sibling 86). Conditioning regimens were mainly busulfan (BU) + cyclophosphamide (CY)/fludarabine (Flu) or total body irradiation (TBI) + CY/Flu. Antihuman thymocyte globulin (ATG) was added in haploidentical and unrelated transplants. Plasma EBV DNA was monitored once to twice weekly in the first 3 months after allo-HSCT with real time quantitative polymerase chain reaction (RQ-PCR). EBV viremia was diagnosed when EBV DNA was more than 5 × 10(2) copies/ml but without symptoms. Acyclovir (10 mg/kg, intravenous drip, 8 h) was used for preemptive therapy and immuno-suppressants were decreased if possible. RESULTS: Totally 33 patients (11.9%) developed EBV viremia with a median time at day 44 (day 19 to day 84). The incidences of EBV viremia in the transplants from matched sibling, haploidentical, unrelated donors were 0, 15.5%, 20.0%, respectively. There was no significant difference between haploidentical and unrelated transplants (P = 0.09), but much less EBV viremia was seen in matched sibling transplant (P = 0.001). Twenty of 33 patients (60.6%) had complete response to preemptive therapy. The median time to reach EBV DNA negative in plasma was 11 (4 - 56) d. The median duration of preemptive therapy was 21 (14 - 60) d. Both univariate and multivariate analysis indicated that haploidentical and unrelated transplants, acute graft versus host disease (GVHD) were the risk factors for EBV viremia. Two-year overall survival in the patients with EBV viremia was significantly lower than that without EBV viremia (54.2% vs 72.1%, P = 0.006). CONCLUSIONS: Our large clinical study has demonstrated that preemptive therapy with acyclovir that is guided by EBV viremia is effective in majority of the patients with high-risk for EBV reactivation after allo-HSCT, which may further decrease the risk for developing life-threatening EBV disease or post-transplantation lymphoproliferative disorder. Haploidentical and unrelated transplants, acute GVHD are the risk factors for EBV viremia which has negative impact on survival.

[Role of HLA protein three-dimensional conformation difference in unrelated hematopoietic stem cell transplantation].

This study was purposed to investigate the value of Histocheck and HLA-Matchmaker softwares in evaluating influence of HLA protein three dimensional conformation among individuals on outcome of unrelated donor hematopoietic stem cell transplantation (URHSCT). Data of the HLA-A/B/C/DRB1/DQB1 genotypes from 62 cases of URHSCT (HLA-allele 10/10 match 30 cases, 9/10 match 32 cases) were input into Histocheck and HLA-Matchmaker softwares respectively. The relationship between the software dissimilar scores and the 1 year overall survival (OS), incidence of aGVHD of III-IV grade and relapse rate was analyzed. The results showed that (1) with increase of the Histocheck scores, incidence of aGVHD of III-IV increased from 0% to 20% (p = 0.25), while no or mild aGVHD occurred in 70% cases with the high scores. For the relapsed cases, there was no significant difference between the cases with low scores and with highest scores (relapse rate 20%) except that 9 cases had no relapse in the group with higher score (11 - 20). (2) the analysis using HLA matchmaker software showed that incidence of aGVHD of III-IV grade increased with the increase of numbers of mismatch Eplets, arranging from 0% to 30%, the incidence of moderate aGVHD reduced (p = 0.019), whereas 60% cases in highest scores group had moderate aGVHD. No relapse occurred in the group with higher scores (≥ 3) (n = 10), whereas high relapse rate appeared in the lower score group (20%, p = 0.54). It is concluded that the value of Histocheck and HLA-Mtchmaker software for analysing the outcome of URHSCT may be similar despite of different calculating methods; for the certain pair of recipient and donor, correlation of the two score systems with incidence of aGVHD and relapse rate is similar, but with less accuracy; The HLA Matchmaker software appears better than Histocheck software in terms of correlation.

[Influence of HLA-A/B/C/DRB1/DQB1 on unrelated donor hematopoietic stem cell transplantation].

This study was purposed to explore the influence of number and locus of HLA allele mismatch on unrelated donor hematopoietic stem cell transplantation (URHSCT) in Chinese Han population. Total 10 alleles within the HLA-A/B/C/DRB1/DQB1 loci were analyzed by PCR-SSP for 101 pairs of donor and recipients who received URHSCT. 101 cases of URHSCT were divided into four groups: HLA-allele 10/10 match (n = 30), 9/10 (n = 32), 8/10 (n = 31) and 7/10 match (n = 8). The correlation of the HLA with overall survival (OS ≥ 1 year), incidence of acute GVHD (aGVHD) of grade II to IV and relapse rate of primary diseases were evaluated. The results showed that (1) The OS rates in HLA-10/10 and 9/10 groups were higher than that in HLA-8/10 match group (78% and 82% vs 50%, p = 0.39); incidence of aGVHD in the HLA-10/10 were lower than that in HLA-9/10 and HLA-8/10 group (0% vs 10% and 10%; p = 0.28); relapse rates among the 3 groups were close (16%, 18% and 20%, respectively). Although there were only 8 cases in HLA-7/10 match URHSCT, the data indicated that they were safe and effective; (2) Compared to the HLA-10/10 match URHSCT (n = 30), the HLA-C mismatch URHSCT (n = 12) harbored higher incidence of severe aGVHD (0% vs 25%, p = 0.006), longer OS (77% vs 85%, p = 0.30), and tendency to low relapse rate (8% vs17%, p = 0.47); (3) According to HLA-C1/C2, the ligands of inhibitory KIR, the 42 cases of HLA-10/10 match URHSCT and HLA-C mismatch URHSCT were grouped into donor/recipient HLA-C1/C2 match and mis-match subgroups. There was no difference between the two subgroups for OS, incidence of aGVHD and relapse rate (78% vs 80%, 14% vs 20%, and 5% vs 20%). It is concluded that for 0 to 2 locus of HLA allele mismatch in URHSCT, the fewer mismatch numbers, the longer OS, but with similar aGVHD incidence and the relapse rate; triple HLA allele mismatch (HLA-7/10 match) is safe in URHSCT. The HLA-C mismatch may be related to higher incidence of aGVHD and lower relapse rate and prolonged OS, remaining to be further studied.