非清髓异基因造血干细胞移植治疗慢性粒细胞白血病

目的　探讨非清髓异基因造血干细胞移植 (NST)治疗慢性粒细胞白血病 (CML)的临床效果。方法　对 4例慢性粒细胞白血病患者进行了非清髓异基因造血干细胞移植 ,均采用以氟达拉宾为基础的非清髓预处理方案。回输CD+ 3 4 细胞分别为 9.78× 10 6/Kg、16.5 6× 10 6/Kg、2 .5 6×10 6/Kg和 2 .0 6× 10 6/Kg。结果　 4例均顺利渡过造血抑制期。 4例患者移植后WBC >1.0× 10 9/L ,中性粒细胞 >0 .5× 10 9/L ,时间分别为 +19天、+16天、+13天和 +14天 ;血小板 >2 0× 10 9/L时间分别为 +8天、+12天、+18天和 +2 2天。 2例骨髓细胞混合嵌合体形成 +15～ +2 3天 ,完全嵌合体形成 +2 3～ +4 3天 ;另 2例均于 +17天形成完全嵌合体。 4例均未发生急性移植物抗宿主病 ,例 1于第 5次供者淋巴细胞输注后发生皮肤慢性移植物抗宿主病 ,例 3于第 7次供者淋巴细胞输注后发生慢性移植物抗宿主病。 3例于非清髓异基因造血干细胞移植后 6～ 12个月出现移植物抗白血病。 4例均未发生肝静脉阻塞病、出血性膀胱炎及间质性肺炎。随诊 2～ 2 4个月 ,仍全部存活。结论　非清髓异基因造血干细胞移植治疗慢性粒细胞白血病简便、安全、并发症及支持治疗少、疗效较好。     

Prognostic impact of minimal residual disease analysis by flow cytometry in patients with acute myeloid leukemia before and after allogeneic hemopoietic stem cell transplantation

Allogeneic stem cell transplantation (allo‐SCT) has become the treatment of choice in patients with intermediate‐risk and high‐risk acute myeloid leukemia (AML). The quality of response to treatment, assessed in terms of detection of minimal residual disease (MRD), has been consistently associated with prognosis and clinical outcome in patients with AML. The aim of the present study was to evaluate the prognostic impact of analyzing MRD in bone marrow using 4‐color multiparametric flow cytometry (MFC) in 29 patients with AML before and after allo‐SCT. Eighteen patients who were shown to be MRD‐negative [≤0.1% leukemia‐associated immunophenotypes (LAIPs)] by MFC at transplantation and underwent allo‐SCT had lower rates of relapse (15% vs. 66%, P = 0.045), better overall 1‐yr survival (83% vs. 52%, P = 0.021) and a lower cumulative incidence of relapse (P = 0.032) than patients who were MRD‐positive (>0.1%). All post‐transplant MRD‐positive patients underwent a therapeutic intervention after transplant (tapering of immunosuppression, donor lymphocyte infusion, or re‐transplant) with the intention of preventing relapse. Disease was controlled and MRD disappeared in five of these patients. Disease recurred in the other seven patients. We can conclude that follow‐up with MFC for the detection of MRD in AML before and after SCT is useful for predicting relapse. In the post‐transplant setting, monitoring of MRD by MFC could be a key preemptive intervention.     

Successful immunotherapy in early relapse of acute myeloid leukemia after nonmyeloablative allogeneic stem cell transplantation

We report on a 35-year-old woman who underwent allogeneic stem cell transplantation (SCT) in second complete remission (CR) of acute myeloid leukemia (AML) after reduced-intensity conditioning with fludarabine and 2 Gy of total body irradiation. For graft-versus-host disease (GVHD) prophylaxis, cyclosporin A (CsA) and mycophenolate mofetil (MMF) were given. On day 27 after SCT complete hematological remission and donor chimerism was documented. However, in CD34(+) bone marrow cells 28% of recipient hematopoiesis persisted. On day +59 leukemic relapse occurred. After discontinuation of CsA and onset of GVHD, complete donor chimerism and hematological CR were achieved which has been maintained for 14 months.     

Infections after allogeneic hematopoietic stem cell transplantation with a nonmyeloablative conditioning regimen

Hematopoietic cell transplantation (HCT) following nonmyeloablative conditioning (NMSCT) may be associated with a reduced risk of infection compared to standard allogeneic HCT. We retrospectively analyzed incidence and risk factors of infection in 62 patients undergoing NMSCT with low-dose TBI +/- fludarabine and postgrafting CsA and MMF. The proportion of patients with any infection was 77%, but the majority of infectious events occurred beyond day 30. Donor other than sibling, older age, early disease and male gender were significant risk factors. The incidence of bacteremia was 55% at 1 year and the number of bacteremic episodes was 0.9 per patient (0.08 before day 30). The risk of bacteremia increased with older age and the use of a donor other than an HLA-identical sibling, but not with neutropenia. The incidence of infections other than bacteremia correlated with the use of corticosteroids. The risk of CMV infection increased with high-risk CMV serology, and risk of CMV disease with high-risk CMV serology, older age, first transplantation and a diagnosis of lymphoma. In conclusion, after NMSCT, infections are not frequent in the first 30 days post transplant but careful long-term monitoring is necessary thereafter.     

Kinetics of engraftment in patients with hematologic malignancies given allogeneic hematopoietic cell transplantation after nonmyeloablative conditioning

We analyzed the kinetics of donor engraftment among various peripheral blood cell subpopulations and their relationship to outcomes among 120 patients with hematologic malignancies given hematopoietic cell transplantation (HCT) after nonmyeloablative conditioning consisting of 2 Gy total body irradiation (TBI) with or without added fludarabine. While patients rapidly developed high degrees of donor engraftment, most remained mixed donor/host chimeras for up to 180 days after HCT. Patients given preceding chemotherapies and those given granulocyte colony-stimulating factor-mobilized peripheral blood mononuclear cell (G-PBMC) grafts had the highest degrees of donor chimerism. Low donor T-cell (P = .003) and natural killer (NK) cell (P = .004) chimerism levels on day 14 were associated with increased probabilities of graft rejection. High T-cell chimerism on day 28 was associated with an increased probability of acute graft-versus-host disease (GVHD) (P = .02). Of 93 patients with measurable malignant disease at transplantation, 41 achieved complete remissions a median of 199 days after HCT; 19 of the 41 were mixed T-cell chimeras when complete remissions were achieved. Earlier establishment of donor NK-cell chimerism was associated with improved progression-free survival (P = .02). Measuring the levels of peripheral blood cell subset donor chimerisms provided useful information on HCT outcomes and might allow early therapeutic interventions to prevent graft rejection or disease progression.     

Treatment of T-prolymphocytic leukemia with nonmyeloablative allogeneic stem cell transplantation

AIM: T-prolymphocytic leukemia (T-PLL) is a rare disease of the elderly characterized by a high white blood cell count and organomegaly, and is currently incurable. Our aim was to elicit graft-versus-leukemia reactions in a patient with T-PLL. METHODS: A 52-yr-old woman with refractory T-PLL underwent a nonmyeloablative regimen followed by allogeneic peripheral blood stem cell transplantation (a "minitransplant") from her HLA-matched sibling. RESULTS: There was no treatment related toxicity other than neutropenia. Engraftment was successful. The patient experienced no graft-versus-host disease (GVHD) at any time but, on day 84 after transplantation, had a relapse in the central nervous system. Despite infusion of donor lymphocytes and intralumbar chemotherapy, she died on day 157 of systemic disease. CONCLUSION: The reasons why treatment may have failed are discussed (nature of disease, disease progression, treatment schedule).     

Imatinib preceding allogeneic stem cell transplantation in chronic myeloid leukemia

In 37 adults with chronic myeloid leukemia undergoing allogeneic stem cell transplantation imatinib prior to transplant had no discernible negative impact on 100-day mortality (13%) and severe acute (22%) or extensive chronic graft-versus- host disease (31%). After a median of 203 days (range: 18-1419) overall and progression-free survival rates are 62% and 54%, respectively.     

Preemptive immunotherapy in childhood acute myeloid leukemia for patients showing evidence of mixed chimerism after allogeneic stem cell transplantation

Previous studies have shown that children with acute myeloid leukemia (AML) who developed mixed chimerism (MC) were at high risk for relapse after allogeneic stem-cell transplantation (allo-SCT). We investigated the feasibility of intensified preemptive immunotherapy in children receiving allo-SCT for AML. Eighty-four children were registered in our trial from May 2005 to April 2009; of these, 71 fulfilled the inclusion criteria and were treated according to the study protocol. Serial and semiquantitative analyses of posttransplantation chimerism were performed. Defined immunotherapy approaches were considered in MC patients. Continuous complete chimerism (CC) was observed in 51 of 71 patients. MC was detected in 20 patients and was followed by immunotherapy in 13. Six of 13 MC patients returned to CC without toxicity and remained in long-term remission. Overall, the probability of event-free survival (pEFS) was 66% (95% confidence interval [95% CI] = 53%-76%) for all patients and 46% (95% CI = 19%-70%) in MC patients with intervention; however, this number increased to 71% (95% CI = 26%-92%) in 7 of 13 MC patients on immunotherapy who were in remission at the time of transplantation. All MC patients without intervention relapsed. These results suggest that MC is a prognostic factor for impending relapse in childhood AML, and that preemptive immunotherapy may improve the outcome in defined high-risk patients after transplantation.     

The significance of graft-versus-host disease and pretransplantation minimal residual disease status to outcome after allogeneic stem cell transplantation in patients with acute lymphoblastic leukemia

Relapse is the major cause of treatment failure after allogeneic stem cell transplantation (SCT) in patients with acute lymphoblastic leukemia. Minimal residual disease (MRD) was analyzed before SCT in 30 patients with acute lymphoblastic leukemia. The aim was to determine whether the level of MRD before transplantation was correlated with outcome. Fifteen patients were found to have high-level MRD (10(-2) to 10(-3)), 10 had low-level MRD (< 10(-3)), and 5 were MRD(-). Among MRD(-) patients the probability of relapse was 0 in 5, which was less than in MRD(+) patients (13 of 25) (P =.05). No major difference was found between the high- and low-level MRD(+) groups. Among the MRD(+) patients, only 2 of 11 with acute and chronic graft-versus-host disease had a relapse, versus 11 of 14 without (P =.005). In conclusion, for patients entering transplantation while they have residual disease, a combination of acute and chronic graft-versus-host disease may be needed to decrease the risk of relapse after SCT.     

异基因造血干细胞移植治疗慢性粒细胞白血病长生存分析

目的:评价异基因造血干细胞移植(allo-HSCT)治疗慢性粒细胞白血病(CML)的疗效,并分析影响CML长生存的预后因素。方法:118例CML患者包括慢性期88例、加速期8例、急变期22例,其中83例接受相关移植、35例无关移植。预处理方案:36例患者用全身照射(TBI)联合环磷酰胺联合(Cy)、82例改良BuCy(白消安、环磷酰胺和阿糖胞苷)。移植物抗宿主病(GVHD)预防:68例相关人类白细胞抗原(HLA)全相合移植用环孢素(CsA)和甲氨蝶呤(MTX),50例无关供者及相关1个以上位点不合者采用CsA、MTX、抗胸腺细胞球蛋白(ATG)或麦考酚酸酯(MMF)。Cox模型分析影响长生存的因素。结果:118例患者除3例死于预处理相关毒性(RRT)外其余均获造血重建。移植后5年累计感染发生率为42.6%,巨细胞病毒血症累计阳性率为41.6%。Ⅱ～Ⅳ度急性GVHD累计发生率为33.3%,其中相关全相合供者(MSD)和无关、相关不相合供者(MRD/URD)发生率分别为23.1%和46.9%(P=0.01);1年累计慢性GVHD发生率为47.8%,其中MSD和MRD/URD慢性GVHD发生率分别为51.4%和42.2%(P=0.260)。GVHD致死率为18.3%。移植后5年白血病累计复发率为17%,其中MSD和MRD/URD复发率分别为12.5%和23.9%%(P=0.228)。5年累计总生存(OS)和无病生存(DSF)率分别为69.5%和62.6%,其中MSD与MRD/URD的5年OS率和DSF率分别为78.5%比57.2%和72.7%比48.3%(P=0.018,P=0.017)。慢性期与加速/急变期的5年OS率和DSF率分别79.9%、36.7%和72.4%、32.6%(P<0.001)。多因素Cox模型分析显示,Ⅱ～Ⅳ度急性GVHD、HLA不相合、诊断至移植时间≥1年为OS的独立危险因素。加速期、急变期和三联、四联GVHD预防方案为影响DSF的独立危险因素。结论:影响CML-allo-HSCT长生存的主要因素是移植的时机、疾病状态、HLA相合程度和移植后GVHD。GVHD是移植后死亡的主要原因。     

Next-generation sequencing-defined minimal residual disease before stem cell transplantation predicts acute myeloid leukemia relapse

In acute myeloid leukemia (AML), the assessment of post-treatment minimal residual disease (MRD) may inform a more effective management approach. We investigated the prognostic utility of next-generation sequencing (NGS)-based MRD detection undertaken before hematopoietic stem cell transplantation (HSCT). Forty-two AML subjects underwent serial disease monitoring both by standard methods, and a targeted 42-gene NGS assay, able to detect leukemia-specific mutant alleles (with >0.5% VAF) (mean 5.1 samples per subject). The prognostic relevance of any persisting diagnostic mutation before transplant (≤27 days) was assessed during 22.1 months (median) of post-transplant follow-up. The sensitivity of the NGS assay (27 MRD-positive subjects) exceeded that of the non-molecular methods (morphology, FISH, and flow cytometry) (11 positive subjects). Only one of the 13 subjects who relapsed after HSCT was NGS MRD-negative (92% assay sensitivity). The cumulative incidence of post-transplant leukemic relapse was significantly higher in the pre-transplant NGS MRD-positive (vs MRD-negative) subjects (P = .014). After adjusting for TP53 mutation and transplant conditioning regimen, NGS MRD-positivity retained independent prognostic significance for leukemic relapse (subdistribution hazard ratio = 7.3; P = .05). The pre-transplant NGS MRD-positive subjects also had significantly shortened progression-free survival (P = .038), and marginally shortened overall survival (P = .068). In patients with AML undergoing HSCT, the pre-transplant persistence of NGS-defined MRD imparts a significant, sensitive, strong, and independent increased risk for subsequent leukemic relapse and death. Given that NGS can simultaneously detect multiple leukemia-associated mutations, it can be used in the majority of AML patients to monitor disease burdens and inform treatment decisions.     

Monitoring of acute myeloid leukemia patients after allogeneic stem cell transplantation employing semi-automated CD34+ donor cell chimerism analysis

Determination of donor chimerism profiles in blood or bone marrow from patients with allogeneic stem cell transplantation (SCT) is useful for monitoring engraftment or predicting relapse, when specific molecular markers are lacking. CD34+ donor cell chimerism (DCC) analysis in peripheral blood samples from CD34+ acute myeloid leukemia (AML) and myleodysplastic syndrome (MDS) patients proved to be a highly sensitive diagnostic tool that is useful to detect imminent relapse significantly earlier compared to total white blood cell donor cell chimerism monitoring. However, flow-cytometric enrichment of CD34+ cells requires high efforts to human resources and equipment. We present a novel semi-automated CD34+ DCC analysis procedure—employing a magnetic cell-enrichment device, DNA extraction, and short tandem repeat profiling—without the need for flow-cytometric cell sorting. Monitoring 85 patients with AML and MDS over a period of 4 years 24 relapses were detected. Semi-automated peripheral blood CD34+ DCC was diminished below 80 % in all cases of systemic relapse. Significant decrease of the CD34+ DCC value was detected 29–42 days before overt cytological relapse. Our method provides a rapid and sensitive tool for monitoring AML and MDS patients after allogeneic SCT with regard to engraftment and early detection of relapse. Here, we propose a novel semi-automated procedure for CD34+ DCC analysis after allogeneic SCT that is simple, reliable, and therefore applicable in all hematologic laboratories.     

Molecular assessment of erythroid lineage chimerism following nonmyeloablative allogeneic stem cell transplantation

OBJECTIVE: Nonmyeloablative conditioning regimens for allogeneic stem cell transplantation are now commonly used in the treatment of patients with hematologic malignancies. Since this treatment often results in the establishment of mixed hematopoietic chimerism, this approach may also prove to be useful in the treatment of nonmalignant disorders, such as sickle cell disease and thalassemia major. To apply this approach to these diseases, it will be necessary to determine the levels of donor erythropoiesis required to correct hemolysis and ameliorate disease symptoms. Current methods for measuring hematopoietic chimerism are based on DNA polymorphisms that distinguish recipient from donor. These methods accurately measure donor leukocyte engraftment but do not quantify the relative contributions of recipient and donor erythropoiesis following transplant. METHODS: To specifically measure erythroid-lineage chimerism, we used pyrosequencing of the sickle cell mutation to quantify the relative levels of normal and sickle beta-globin mRNA in patient samples. Results of beta-globin RNA chimerism were compared to assessment of beta-globin DNA chimerism as well as analysis of short tandem repeat (STR) polymorphisms, cytogenetics, and hemoglobin electrophoresis. RESULTS: Donor engraftment was measured in two adult patients following nonmyeloablative stem cell transplant for sickle cell disease. In Patient 1, 25 to 30% of peripheral leukocytes were donor derived after day 41. In contrast, more than 55% of peripheral blood beta-globin mRNA was of donor origin, and these results correlated with posttransplant clinical improvement. Patient 2 achieved 40 to 50% donor leukocyte engraftment from day 33 onward. This was associated with 70 to 100% peripheral blood donor beta-globin mRNA. CONCLUSIONS: These studies demonstrate that relatively low levels of donor leukocyte engraftment can be associated with higher levels of donor erythropoiesis and with significant clinical improvement. Pyrosequencing of lineage-specific mRNA directly measures functional reconstitution of donor cells and provides valuable information that can affect clinical decisions in patients with nonmalignant diseases following allogeneic transplant.