Outcome of myeloablative allogeneic peripheral blood hematopoietic stem cell transplantation for refractory/relapsed AML patients in NR status

Allogeneic Stem Cell Transplantation in Refractory Acute Myeloid Leukaemia

Refractory acute myeloid leukaemia is very difficult to treat and represents an unmet clinical need. In recent years, new drugs and combinations of drugs have been tested in this category, with encouraging results. However, all treated patients relapsed and died from the disease. The only curative option is allogeneic transplantation through a graft from a healthy donor immune system. Using myeloablative conditioning regimens, the median overall survival regimens is 19%. Several so-called sequential induction chemotherapies followed by allogeneic transplantation conditioned by reduced intensity regimens have been developed, improving the overall survival to 25-57%. In the allogeneic transplantation field, continuous improvements in practices, particularly regarding graft versus host disease prevention, infection prevention, and treatment, have allowed us to observe improvements in survival rates. This is true mainly for patients in complete remission before transplantation and less so for refractory patients. However, full myeloablative regimens are toxic and carry a high risk of treatment-related mortality. In this review, we describe the results obtained with the different modalities used in more recent retrospective and prospective studies. Based on these findings, we speculate how allogeneic stem cell transplantation could be modified to maximise its therapeutic effect on refractory acute myeloid leukaemia.

Pretransplantation predictors of survival in nonremission acute myeloid leukemia treated with haploidentical transplantation using steroid-based GVHD prophylaxis

Haploidentical hematopoietic cell transplantation (HCT) using glucocorticoids for acute graft-versus-host disease prophylaxis (GC-haplo) may become a curative treatment option for nonremission acute myeloid leukemia (AML). This retrospective study aimed to identify pre-HCT predictors of survival in a cohort of 97 nonremission AML treated with GC-haplo in Hyogo Medical University Hospital between 2010 and 2020. Relapse and primary induction failure included in 70 (72%) and 27 (28%) patients, respectively. Sixty-one patients (63%) had undergone previous HCT. Multivariate analysis revealed that ≤ 6 months' duration between first complete remission (CR1) and first relapse (Rel1) (CR1-Rel1 interval) (hazard ratio 2.11, 95% confidence interval [CI] 1.15-3.89, P = 0.016) and serum albumin before starting the conditioning treatment of ≤ 3.5 g/dL (hazard ratio 1.80, 95%CI 1.09-2.96, P = 0.022) as risk factors for overall survival. Among three groups categorized according to serum albumin and CR1-Rel1 interval, the best 3-year overall survival was observed in patients with albumin > 3.5 g/dL and CR1-Rel1 interval > 6 months or primary induction failure (50.2%, 95%CI 28.9%-68.3%, P < 0.001), revealing that survival could be predicted using albumin and past CR duration in patients with very high-risk AML not in remission before GC-haplo.

Human mesenchymal stem cells derived exosomes inhibit the growth of acute myeloid leukemia cells via regulating miR-23b-5p/TRIM14 pathway

Background

Acute myeloid leukemia (AML) is a malignancy commonly seen in adults. Previous studies indicated that TRIM14 played a tumorigenic role in various types of cancer and miR-23b-5p was down-regulated in human mesenchymal stem cell-derived exosomes (HMSC-exos) of AML patients. However, their roles in AML remains unclear. Our study aims to investigate the role of TRIM14 and miR-23b-5p in the pathogenesis of AML.

Materials and methods

The blood specimen was collected from de novo AML patients and healthy donators. Exosomes were extracted from the culture medium of human mesenchymal stem cells under ultracentrifugation. Then exosomes were co-cultured with AML cells to determine the effect of their contents. The cell proliferation was detected by cell counting kit-8 assay, whereas the cell apoptosis was detected by flow cytometry. The expression of miR-23b-5p and TRIM14 was silenced or overexpressed to explore their biological functions in AML. Luciferase reporter assay was conducted to validate the interaction between miR-23b-5p and TRIM14. Gene expression was determined by quantitative real-time PCR and immunoblots.

Results

TRIM14 was significantly increased in AML patients and cell lines. The inhibition of TRIM14 significantly reduced the proliferation and induced the apoptosis of AML cells via activating PI3K/AKT pathway, whereas its overexpression exhibited reversed effects. HMSC-exos could suppress the proliferation of AML cells through the delivery of miR-23b-5p. Moreover, miR-23b-5p inhibited the transcription of TRIM14 by binding on its 3’UTR region. Overexpression of TRIM14 exhibited reversed effect against the function of miR-23b-5p mimic.

Conclusion

TRIM14 could promote the proliferation of AML cells via activating PI3K/AKT pathway, which was reversed by HMSC-exos through delivering miR-23b-5p. These findings indicated that miR-23b-5p and TRIM14 could be applied as potential targets for the treatment of AML.

Supplementary Information

The online version contains supplementary material available at 10.1186/s10020-021-00393-1.

Allogeneic Hematopoietic Cell Transplantation for Adolescent and Young Adult Patients with Acute Myeloid Leukemia

Limited data exist regarding the outcomes of allogeneic hematopoietic cell transplantation (allo-HCT) among adolescent and young adult (AYA) patients with acute myeloid leukemia (AML). Here we analyzed the features and outcomes of AYA patients with AML who had achieved complete remission (CR) and those who had not (non-CR) at allo-HCT. We retrospectively analyzed 2350 AYA patients with AML who underwent allo-HCT with a myeloablative conditioning regimen and who were consecutively enrolled in the Japanese nationwide HCT registry. The difference in overall survival (OS) between younger (age 16 to 29 years) and older AYA (age 30 to 39 years) patients in CR at transplantation was not significant (70.2% versus 71.7% at 3 years; P = .62). Meanwhile, this difference trended toward a statistical significance between younger and older AYA patients in non-CR at transplantation (39.5% versus 34.3% at 3 years; P = .052). In AYA patients in CR and non-CR, the age at transplantation did not affect relapse or nonrelapse mortality (NRM). In AYA patients in CR, no difference in OS was observed between those who received total body irradiation (TBI) and those who did not (71.1% versus 70.5% at 3 years; P = .43). AYA patients who received TBI-based conditioning had a significantly lower relapse rate and higher NRM than those who underwent non-TBI-based conditioning (relapse: 19.8% versus 24.1% at 3 years [P = .047]; NRM: 14.7% versus 11.1% at 3 years [P = .021]). In contrast, among the non-CR patients, there were no differences between the TBI and non-TBI groups with respect to OS (P = .094), relapse (P = .83), and NRM (P = .27). Our data indicate that outcomes may be more favorable in younger AYA patients than in older AYA patients in non-CR at transplantation, and that outcomes of TBI-based conditioning could be comparable to those of non-TBI-based conditioning for AYA patients.

Decitabine prior to salvaged cord blood transplantation for acute myeloid leukaemia/myelodysplastic syndrome not in remission

WHAT IS KNOWN AND OBJECTIVE

Many refractory/relapsed haematological malignancies, in non-remission state, still have poor prognosis even after allogeneic haematopoietic stem cell transplantation. Recently, decitabine or umbilical cord blood transplantation (UCBT) seemed to be effective in these patients. However, few studies have added decitabine to myeloablative conditioning regimens for UCBT in patients with haematological malignancies not in remission. Therefore, the objective was to evaluate the clinical outcomes of patients with refractory/relapsed acute myeloid leukaemia (AML) or myelodysplastic syndrome (MDS) using decitabine as part of a myeloablative conditioning regimen prior to salvaged unrelated UCBT at our centre.

METHODS

We enrolled 20 consecutive patients with refractory/relapsed AML/MDS between 2013 and 2018. All patients were in non-remission state before transplantation. All transplants were performed with decitabine as part of the myeloablative conditioning regimen, which was decitabine + fludarabine/busulfan/cyclophosphamide.

RESULTS AND DISCUSSION

All patients achieved neutrophil and platelet engraftment. Incidence of grade III/IV acute graft-vs-host disease (GVHD) was 20.0%, which was also decreased compared to non-decitabine group (P = .025). The median follow-up time after UCBT was 29 months (range 14-64 months). The 2-year probability of GVHD-free relapse-free survival (GRFS) was higher in the decitabine group. Univariate showed that the decitabine group was associated with a higher GRFS than the non-decitabine group. The estimated probability of overall survival and relapse was 55% and 20.0%, respectively.

WHAT IS NEW AND CONCLUSIONS

Our results suggest that addition of decitabine as part of the myeloablative conditioning regimen prior to UCBT for refractory/relapsed AML/MDS in patients who are not in remission is safe and might be an effective treatment option.

Clinical Benefits of Preconditioning Intervention in Patients with Relapsed or Refractory Acute Myelogenous Leukemia Who Underwent Allogeneic Hematopoietic Cell Transplantation: A Kanto Study of Group for Cell Therapy Multicenter Analysis

A multicenter retrospective study was conducted to evaluate the clinical significance of preconditioning intervention (PCI) before allogeneic hematopoietic cell transplantation (HCT) in patients with acute myelogenous leukemia (AML) not in remission. The study cohort consisted of 519 patients classified according to the intensity (intensive/moderate) of PCI and their response to PCI. The group treated with PCI had higher blast counts in the peripheral blood (PB) and had a lower overall survival (OS) rate (P < .001) and higher nonrelapse mortality (NRM) rate (P = .035) compared with those without PCI (no PCI group). Approximately 40% of the patients (68 of 236) achieved a good response to PCI (good PCI group), and those patients had lower blast counts in the PB compared with the group with poor response to PCI (poor PCI group). OS in the good PCI group was comparable to that in the no PCI group and significantly better than that in the poor PCI group (hazard ratio, .54; 95% confidence interval, .39 to .77; P < .001). However, OS was significantly lower in patients with intensive/moderate PCI compared with the no PCI group. These results suggest that PCI increases NRM without decreasing the post-transplantation relapse rate, but may be beneficial for patients with lower blast counts in PB irrespective of its intensity.

[HLA-10/10 matched unrelated donor versus sibling donor hematopoietic stem cell transplantation for adult acute myeloid leukemia]

目的

观察人类白细胞抗原（HLA）匹配的无关供者造血干细胞移植（MUD-HSCT）治疗成人急性髓系白血病（AML）的疗效。

方法

回顾性分析2008年1月至2017年4月接受MUD-HSCT的成人AML病例资料，并以同期同胞全相合供者移植（MSD-HSCT）病例为对照，分析两组患者总生存（OS）率、无病生存（DFS）率、复发率、非复发死亡率（NRM）、植活率及急慢性移植物抗宿主病（aGVHD、cGVHD）发生率的差异。

结果

共247例连续性病例入组，MUD组46例，MSD组201例。除1例MSD组患者早期死亡外，两组患者均获粒细胞植活，但MUD组中位植活时间长于MSD组（15 d对14 d，P=0.017），血小板累积植活率差异无统计学意义（93.5%对98.0%，P=0.128）。两组患者aGVHD、cGVHD累积发生率差异无统计学意义（50.0%对46.3%，P=0.421；37.8%对43.0%，P=0.581）。与MSD组相比，MUD组患者3年累积NRM显著升高（22.0%对10.4%，P=0.049），但累积复发率差异无统计学意义（20.5%对28.3%，P=0.189）。两组患者3年OS率和DFS率差异均无统计学意义（61.6%对63.3%，P=0.867；57.5%对61.6%，P=0.760）。经多因素分析发现，患者年龄≥45岁、移植前第2次完全缓解（CR₂）及以上或未缓解状态、有髓外浸润病史及Ⅲ~Ⅳ度aGVHD是影响生存的独立危险因素。

结论

与MSD-HSCT相比，MUD-HSCT治疗成人AML的NRM较高，粒细胞植活中位时间较长，但GVHD发生率、复发率、OS率及DFS率并无显著差异，是缺乏MSD的成人AML患者的理想替代移植方案。

Prognostic index for patients with relapsed or refractory acute myeloid leukemia who underwent hematopoietic cell transplantation: a KSGCT multicenter analysis

A multicenter retrospective study was performed to explore a prognostic scoring index in order to identify a population who are least likely to benefit from allogeneic hematopoietic cell transplantation (HCT) in patients with relapsed or refractory acute myeloid leukemia (AML). The cohort included 519 patients with AML, who received HCT between 2005 and 2015 at a status of relapse or primary induction failure. Multivariate analysis demonstrated five independent predictors for OS, including C-reactive protein ≥ 1 mg/dL, peripheral blood blast fraction ≥ 20%, poor-risk karyotype, performance status ≥ 2, and bone marrow unrelated donor as a stem cell source. A prognostic scoring index was explored based on these predictors, and successfully separated the cohort into four groups. At 2 years, OS was 47%, 24%, 8%, and 0% for Good (Score 0, 1: n = 118), Intermediate-1 (Score 2: n = 75), Intermediate-2 (Score 3: n = 39), and Poor (Score 4: n = 24), respectively (P < 0.001). The predicting value of the index was confirmed in a validation cohort. Although a further validation study is warranted, the scoring index may be useful to predict survival and to identify the population with the lowest survival prior to HCT in patients with relapsed or refractory AML.

[Allogeneic hematopoietic stem cell transplantation for treatment of refractory and relapsed acute myeloid leukemia: outcomes and prognostic factors]

目的

评价异基因造血干细胞移植（allo-HSCT）治疗难治/复发急性髓系白血病（AML）的疗效，并对预后相关因素进行分析。

方法

回顾性分析allo-HSCT治疗99例难治/复发AML患者总体生存（OS）率、无病生存（DFS）率、移植物抗宿主病（GVHD）发生率、移植相关死亡率（TRM）及复发率，并分析影响预后的危险因素。

结果

全部99例患者中男59例，女40例，中位年龄为35（6~58）岁，均接受清髓性预处理。所有患者中性粒细胞均达植入标准，中位植活时间为14（9~25）d。移植后100 d Ⅱ~Ⅳ度急性GVHD累积发生率为27.3%（95% CI 18.9%~36.3%）；2年慢性GVHD累积发生率为33.9%（95%CI 24.6%~43.5%），其中广泛型慢性GVHD累积发生率为9.3%（95%CI 4.5%~16.1%）。移植后3年OS、DFS、TRM率分别为45.0%（95%CI 34.6%~55.4%）、45.0%（95%CI 34.8%~55.2%）、19.7%（95%CI 12.4%~28.3%），复发率为36.6%（95%CI 26.9%~46.4%）。多因素分析显示，影响OS的独立危险因素包括移植前未缓解[P=0.009，HR=2.21（95%CI 1.22~4.04）]、初诊WBC>50×10⁹/L[P=0.024，HR=2.11（95%CI 1.11~4.02）]、供者年龄>35岁[P=0.031，HR=1.96（95%CI 1.06~3.60）]、移植后未发生慢性GVHD[P=0.008，HR=0.38（95%CI 0.18~0.78）]。根据移植前危险因素（移植前未缓解、初诊WBC>50×10⁹/L、供者年龄>35岁）进行危险度分组，具有0、1、2~3个危险因素患者的3年OS率分别为75.0%、46.9%、15.4%（χ²=26.873，P<0.001）。

结论

allo-HSCT是挽救性治疗难治/复发AML的有效手段，复发是影响生存的主要原因。移植前缓解状态、发病时WBC水平、供者年龄及移植后是否发生慢性GVHD是难治/复发AML患者allo-HSCT预后的独立影响因素。

Management of primary refractory acute myeloid leukemia in the era of targeted therapies

Primary refractory acute myeloid leukemia (AML), or primary induction failure, represents a continued challenge in clinical management. This review presents an overview of primary refractory disease and a discussion of risk factors for induction failure, including current evidence regarding the impact of karyotype and molecular mutation status on responsiveness to chemotherapy. We review the evidence for various treatment options for refractory AML including salvage chemotherapy regimens, allogeneic hematopoietic stem cell transplantation, targeted agents, and non-intensive therapies such as hypomethylating agents. A therapeutic approach to this patient population is presented, and several new and emerging therapies are reviewed.

Idarubicin-Intensified Hematopoietic Cell Transplantation Improves Relapse and Survival of High-Risk Acute Leukemia Patients with Minimal Residual Disease

The optimal conditioning regimen of allogeneic hematopoietic stem cell transplantation (allo-HSCT) for high-risk patients with minimal residual disease (MRD) remains controversial. We studied the results in 98 high-risk acute leukemia patients transplanted with idarubicin (IDA)-intensified conditioning regimens between 2012 January and 2017 January. Among these patients, 31 (31.6%) had more than 5% marrow blasts at time of transplantation and 67 patients were in morphologic remission: MRD negative status at time of conditioning was achieved in 39 patients (39.8%), whereas 28 (28.6%) remained carriers of any other positive MRD level in the bone marrow. Three-year relapse estimates of patients with MRD-positive remission was 22.0%, which was remarkably lower than patients with active disease (45.4%, P = .027) but approximate to that of patients in MRD-negative remission (15.5%, P = .522). There were no significant differences in terms of 3-year estimated overall survival (OS) and disease-free survival (DFS) between MRD-positive remission and MRD-negative remission groups (71.4% versus 79.1% [P = .562] and 67.9% versus 76.9% [P = .634], respectively). Moreover, the estimated rates of 3-year OS and DFS of patients in MRD-positive remission were significantly better than those in patients with active disease (71.4% versus 41.9% [P = .033] and 67.9% versus 38.7% [P = .037], respectively). These data indicate that IDA-intensified conditioning allo-HSCT could overcome the negative prognostic impact of MRD.

Allogeneic Hematopoietic Stem Cell Transplantation In Therapy-Related Myeloid Neoplasms (t-MN) of the Adult: Monocentric Observational Study and Review of the Literature

Background

Therapy related myeloid neoplasms (t-MN) occur due to direct mutational events of chemotherapeutic agents and radiotherapy. Disease latency, mutational events and prognosis vary with drugs categories.

Methods

We describe a cohort of 30 patients, 18 females and 12 males, with median age of 52.5 years (range, 20 to 64), submitted to allogeneic stem cell transplantation (HSCT) in our department between September 1999 and March 2017. Patients had a history of solid tumour in 14 cases, haematological disease in 15 cases and both of them in one case. After a median of 36.5 months (range, 4 to 190) from first neoplasm, patients developed t-AML in 19 cases and t-MDS in 11 cases. Molecular abnormalities were detected in 5 patients, while karyotype aberrations were found in 17 patients. Patients received conventional chemotherapy in 14 cases, azacitidine in 10 cases and both of them in one case. Five patients were submitted to HSCT without previous treatment except for supportive therapy.

Results

Seventeen patients obtained sustained CR after SCT, while 8 patients showed resistant or relapsed disease. The remaining five patients died early after SCT. At follow up time (May 2017) 13 patients were alive with a median OS of 48 months (range 3–195), while 17 patients died after a median of 4 months (range 1–27) by relapse mortality in 6 cases and non-relapse mortality in the other 11 patients.

Conclusions

Global OS was 43%. After SCT, 72.2% of patients with t-MN maintained a sustained CR.

Early tapering of immunosuppressive agents after HLA-matched donor transplantation can improve the survival of patients with advanced acute myeloid leukemia

Disease recurrence is the most important obstacle to achieve long-term survival for patients with advanced acute myeloid leukemia (AML) after allogeneic hematopoietic stem cell transplantation (allo-HSCT). In order to reduce the relapse risk and improve the survival, the strategy of early tapering of immunosuppressive agents was prospectively evaluated. Thirty-one patients with advanced AML received early tapering of immunosuppressive drugs, while 32 patients with AML in complete remission (CR) were given the routine tapering of immunosuppressive agents after HLA-matched donor transplantation. All advanced AML patients achieved CR after allo-HSCT. At 24 months after transplantation, relapse incidences were 22% in advanced group and 16% in CR group (P = 0.553); disease-free survival (DFS) and overall survival (OS) were 57.7 and 57.8% in advanced group, while in CR group were 66.6% (P = 0.388) and 66.2% (P = 0.423); immunosuppressive agent-free DFS (IDFS) were similar between two groups (P = 0.407). Acute graft-versus-host disease (aGvHD) incidences were similar between two groups (P = 0.311). Chronic GvHD (cGvHD) incidence was much higher in advanced group than in CR group (70.4 vs 38.7%, P = 0.02), but severe cGvHD had no difference. In multivariate analysis, cGvHD was an independent prognostic factor for lower risk of relapse and better DFS and OS; early tapering of immunosuppressive agents was an independent prognostic factor for cGvHD. The study suggested that advanced AML patients could be directly treated with allo-HSCT and its survival could be improved through the strategy of early tapering of immunosuppressive agents without significant adverse effects ( Clinicaltrials.org NCT03150134).