Long-Term Results of Allogeneic Stem Cell Transplantation in Adult Ph- Negative High-Risk Acute Lymphoblastic Leukemia.

Allogeneic hematopoietic stem cell transplantation (HCT) is standard treatment for adult high-risk (HR) acute lymphoblastic leukemia (ALL) and contributed to the overall improved outcome. We report a consecutive cohort of prospectively defined HR patients treated on German Multicenter Acute Lymphoblastic Leukemia trials 06/99-07/03 with similar induction/consolidation therapy and HCT in first remission. A total of 542 patients (15-55 years) with BCR-ABL-negative ALL were analyzed. Sixty-seven percent received HCT from matched unrelated donors (MUD) and 32% from matched sibling donors (MSD). The incidence of non-relapse mortality (NRM) was 20% at 5 years. NRM occurred after median 6.6 months; the leading cause (46%) was infection. NRM after MUD decreased from 39% in trial 06/99 to 16% in trial 07/03 (P < .00001). Patient age was the strongest predictor of NRM. The 5-year relapse incidence was 23% using MSD and 25% using MUD. Minimal residual disease (MRD) was the strongest predictor of relapse (45% for molecular failure versus 6% for molecular CR; P < .0001). The median follow-up was 67 months, and the 5-year survival rate was 58%. Age, subtype/high risk feature, MRD status, trial and acute GvHD were significant prognostic factors. We provide a large reference analysis with long follow-up confirming a similar outcome of MSD and MUD HCT and improved NRM for MUD HCT over years. MRD has a strong impact on relapse risk, whereas age was the strongest predictor of NRM. New adapted conditioning strategies should be considered for older patients combined with the goal to reduce the MRD level before stem cell transplantation.

Allogeneic hematopoietic stem cell transplantation for adult HLH: a retrospective study by the chronic malignancies and inborn errors working parties of EBMT.

Hemophagocytic lymphohistiocytosis (HLH; hemophagocytic syndrome) is a rare syndrome of potentially fatal, uncontrolled hyperinflammation. Allogeneic hematopoietic stem cell transplantation (allo-HSCT) is indicated in primary, recurrent or progressive HLH, but information about its outcomes in the adult population is limited. We obtained data about 87 adult (≥18 years of age) patients retrospectively reported to the EBMT. The median survival time was 13.9 months. The three and five-year overall survival (OS) was 44% (95% CI 33-54%). Among 39 patients with a follow-up longer than 15 months, only three died. Relapse rate was 21% (95% CI 13-30%), while NRM reached 36% (95% CI 25-46%). Younger patients (<30 years of age) had better prognosis, with an OS of 59% (95% CI 45-73%) at three and five years vs 23% (95% CI 8-37%) for older ones. No difference in survival between reduced and myeloablative conditioning was found. To our knowledge, this is the largest report of adult HLH patients who underwent allo-HSCT. Patients who survive the first period after this procedure can expect a long disease-free survival. Both reduced intensity and myeloablative conditioning have therapeutic potential in adult HLH.

Autologous hematopoietic stem cell transplantation with reduced-intensity conditioning regimens in refractory Takayasu arteritis: a retrospective multicenter case-series from the Autoimmune Diseases Working Party (ADWP) of the European Society for Blood and Marrow Transplantation (EBMT).

Autologous hematopoietic stem cell transplantation (AHSCT) has emerged as a promising treatment option in severely affected and refractory patients with autoimmune diseases. This is a retrospective survey of patients reported to the EBMT registry between 1998 and 2019, who received AHSCT for TAK. Data from six patients treated with AHSCT for refractory TAK have been identified, five were female (83%), median age 25 (9-39) years. All patients were pretreated with a median of 6 (4-8) lines of therapy, including steroids (six patients), methotrexate (five patients), cyclophosphamide, mycophenolate mofetil or infliximab (four patients), tocilizumab or etanercept (two patients). Conditioning included cyclophosphamide and rabbit anti-thymocyte globulin in all patients. At 6 months post transplantation, remission was obtained in all cases, which persisted at 12 months in five cases. Four patients reactivated TAK at a median time of 27 (7-52) months after AHSCT, and three resumed disease-modifying therapy. At last follow-up, all patients were alive, two patients were in remission (off-therapy), two patients improved compared with baseline, and two patients were in complete and partial remission, respectively, under immunosuppressive treatment. This retrospective case-series demonstrates that AHSCT has the potential to provide significant clinical responses in TAK patients, but large prospective trials are necessary to confirm these preliminary data.

Comparison of Dynamic International Prognostic Scoring System and MYelofibrosis SECondary to PV and ET Prognostic Model for Prediction of Outcome in Polycythemia Vera and Essential Thrombocythemia Myelofibrosis after Allogeneic Stem Cell Transplantation.

We aimed to validate the MYelofibrosis SECondary to PV and ET prognostic model (MYSEC-PM) in 159 patients with myelofibrosis secondary to polycythemia vera (PV) and essential thrombocythemia (ET) from the European Society for Blood and Marrow Transplantation registry undergoing transplantation from matched siblings or unrelated donors. Furthermore, we aimed to test its prognostic performance in comparison with the Dynamic International Prognostic Scoring System (DIPSS). Score performance was analyzed using the concordance index (C): the probability that a patient who experienced an event had a higher risk score than a patient who did not (C > .5 suggesting predictive ability). Median follow-up of the total cohort was 41 months (range, 34 to 54), 45 months in post-PV and 38 months in post-ET myelofibrosis. Survival at 1, 2, and 4 years was 70% (95% CI, 63% to 77%), 61% (95% CI, 53% to 69%), and 52% (95% CI, 43% to 61%) for the total cohort; 70% (95% CI, 59% to 80%), 61% (95% CI, 49% to 73%), and 51% (95% CI, 38% to 64%) for post-PV; and 71% (95% CI, 61% to 81%), 61% (95% CI, 50% to 72%), and 54% (95% CI, 42% to 66%) for post-ET myelofibrosis (P = .78). Overall, the DIPSS was not significantly predictive of outcome (P = .28). With respect to the MYSEC-PM, overall survival at 4 years was 69% for the low-risk, 55% for the intermediate 1-risk, 47% for the intermediate 2-risk, and 22% (0% to 45%) for the high-risk groups. The prognostic model was predictive of survival overall (P = .05), whereas groups with intermediate 2 and high risk showed no significant difference (P = .44). Assessment of prognostic utility yielded a C-index of .575 (95% CI, .502 to .648) for the DIPSS, whereas assessment of the MYSEC-PM resulted in a C-statistics of .636 (95% CI, .563 to .708), indicating improvement in prediction of post-transplant survival using the new MYSEC-PM. In addition, transplantations from an unrelated donor in comparison with an HLA-identical sibling showed worse outcome (P = .04), and transplant recipients seropositive for cytomegalovirus in comparison with seronegative recipients (P = .01) showed worse survival. In conclusion, incorporating transplant-specific and clinical and mutational information together with the MYSEC-PM may enhance risk stratification.

Allogeneic hematopoietic stem cell transplantation with myeloablative conditioning for adult cerebral X-linked adrenoleukodystrophy.

The adult cerebral form of X-linked adrenoleukodystrophy (ACALD), an acute inflammatory demyelinating disease, results in a rapidly progressive neurodegeneration, typically leading to severe disability or death within a few years after onset. We have treated 15 men who had developed ACALD with allogeneic hematopoietic stem cell transplantation (HSCT) from matched donors after myeloablative conditioning with busulfan and cyclophosphamide. All patients engrafted and 11 survived (estimated survival 73 ± 11%), 8 with stable cognition and 7 of them with stable motor function (estimated event-free survival 36 ± 17%). Death after transplantation occurred within the first year after HSCT and was caused either primarily by infection (N = 3) or due to disease progression triggered by infection (N = 1). Patients with minor myelopathic symptoms (N = 4) or with no or mild cerebral symptoms pre-transplant (N = 7) had an excellent outcome. In contrast, no patient with major neurological symptoms associated with an extensive involvement of pyramidal tract fibres in the internal capsule (N = 5) survived without cognitive deterioration. Notably, early leukocyte recovery was associated with dismal outcome for yet unknown reasons. All 10 tested survivors showed a reduction of plasma hexacosanoic acid (C26:0) in the absence of Lorenzo's oil. Over time, the event-free survival could be improved from 2 out of 8 patients (25%) before 2013 to 5 out of 7 patients (71%) thereafter. Therefore, allogeneic HSCT appears to be a suitable treatment option for carefully selected ACALD patients when transplanted from matched donors after myeloablative, busulfan-based conditioning.

Long-term outcome after allogeneic hematopoietic cell transplantation for myelofibrosis.

Allogeneic hematopoietic stem cell transplant remains the only curative treatment for myelofibrosis. Most post-transplantation events occur during the first two years and hence we aimed to analyze the outcome of 2-year disease-free survivors. A total of 1055 patients with myelofibrosis transplanted between 1995 and 2014 and registered in the registry of the European Society for Blood and Marrow Transplantation were included. Survival was compared to the matched general population to determine excess mortality and the risk factors that are associated. In the 2-year survivors, disease-free survival was 64% (60-68%) and overall survival was 74% (71-78%) at ten years; results were better in younger individuals and in women. Excess mortality was 14% (8-21%) in patients aged <45 years and 33% (13-53%) in patients aged ≥65 years. The main cause of death was relapse of the primary disease. Graft-versus-host disease (GvHD) before two years decreased the risk of relapse. Multivariable analysis of excess mortality showed that age, male sex recipient, secondary myelofibrosis and no GvHD disease prior to the 2-year landmark increased the risk of excess mortality. This is the largest study to date analyzing long-term outcome in patients with myelofibrosis undergoing transplant. Overall it shows a good survival in patients alive and in remission at two years. However, the occurrence of late complications, including late relapses, infectious complications and secondary malignancies, highlights the importance of screening and monitoring of long-term survivors.

AML: high serum ferritin at initial diagnosis has a negative impact on long-term survival.

Increased serum ferritin (SF) is common in hematologic malignancies; however, its prognostic role in acute myeloid leukemia (AML) is not clearly established. We examined the impact of baseline SF on long-term survival in 137 intensively treated AML patients. Patients and baseline characteristics were retrieved from an AML database at Charité University Medical Center Berlin, Campus Virchow Clinic. After c-reactive protein (CRP)-based adjustment for inflammation, patients were grouped according to their baseline SF level. Survival analysis was performed accordingly. A significant decline in overall survival and relapse-free survival was observed in patients with high SF as compared to those with low SF. Furthermore, elevated baseline SF remained an independent poor prognostic factor within the multivariate analysis and was associated with a significant higher risk of relapse and non-relapse mortality (NRM). In conclusion, our data show that elevated baseline SF has a negative impact on long-term survival in intensively treated AML patients.

Peptide-specific recognition of human cytomegalovirus strains controls adaptive natural killer cells.

Natural killer (NK) cells are innate lymphocytes that lack antigen-specific rearranged receptors, a hallmark of adaptive lymphocytes. In some people infected with human cytomegalovirus (HCMV), an NK cell subset expressing the activating receptor NKG2C undergoes clonal-like expansion that partially resembles anti-viral adaptive responses. However, the viral ligand that drives the activation and differentiation of adaptive NKG2C+ NK cells has remained unclear. Here we found that adaptive NKG2C+ NK cells differentially recognized distinct HCMV strains encoding variable UL40 peptides that, in combination with pro-inflammatory signals, controlled the population expansion and differentiation of adaptive NKG2C+ NK cells. Thus, we propose that polymorphic HCMV peptides contribute to shaping of the heterogeneity of adaptive NKG2C+ NK cell populations among HCMV-seropositive people.

Erratum: Sorafenib promotes graft-versus-leukemia activity in mice and humans through IL-15 production in FLT3-ITD-mutant leukemia cells.

This corrects the article DOI: 10.1038/nm.4484.

Sorafenib promotes graft-versus-leukemia activity in mice and humans through IL-15 production in FLT3-ITD-mutant leukemia cells.

Individuals with acute myeloid leukemia (AML) harboring an internal tandem duplication (ITD) in the gene encoding Fms-related tyrosine kinase 3 (FLT3) who relapse after allogeneic hematopoietic cell transplantation (allo-HCT) have a 1-year survival rate below 20%. We observed that sorafenib, a multitargeted tyrosine kinase inhibitor, increased IL-15 production by FLT3-ITD+ leukemia cells. This synergized with the allogeneic CD8+ T cell response, leading to long-term survival in six mouse models of FLT3-ITD+ AML. Sorafenib-related IL-15 production caused an increase in CD8+CD107a+IFN-γ+ T cells with features of longevity (high levels of Bcl-2 and reduced PD-1 levels), which eradicated leukemia in secondary recipients. Mechanistically, sorafenib reduced expression of the transcription factor ATF4, thereby blocking negative regulation of interferon regulatory factor 7 (IRF7) activation, which enhanced IL-15 transcription. Both IRF7 knockdown and ATF4 overexpression in leukemia cells antagonized sorafenib-induced IL-15 production in vitro. Human FLT3-ITD+ AML cells obtained from sorafenib responders following sorafenib therapy showed increased levels of IL-15, phosphorylated IRF7, and a transcriptionally active IRF7 chromatin state. The mitochondrial spare respiratory capacity and glycolytic capacity of CD8+ T cells increased upon sorafenib treatment in sorafenib responders but not in nonresponders. Our findings indicate that the synergism of T cells and sorafenib is mediated via reduced ATF4 expression, causing activation of the IRF7-IL-15 axis in leukemia cells and thereby leading to metabolic reprogramming of leukemia-reactive T cells in humans. Therefore, sorafenib treatment has the potential to contribute to an immune-mediated cure of FLT3-ITD-mutant AML relapse, an otherwise fatal complication after allo-HCT.

Advice from the Scientific Advisory Board of the Organisation for the Prohibition of Chemical Weapons on riot control agents in connection to the Chemical Weapons Convention.

Compounds that cause powerful sensory irritation to humans were reviewed by the Scientific Advisory Board (SAB) of the Organisation for the Prohibition of Chemical Weapons (OPCW) in response to requests in 2014 and 2017 by the OPCW Director-General to advise which riot control agents (RCAs) might be subject to declaration under the Chemical Weapons Convention (the "Convention"). The chemical and toxicological properties of 60 chemicals identified from a survey by the OPCW of RCAs that had been researched or were available for purchase, and additional chemicals recognised by the SAB as having potential RCA applications, were considered. Only 17 of the 60 chemicals met the definition of a RCA under the Convention. These findings were provided to the States Parties of the Convention to inform the implementation of obligations pertaining to RCAs under this international chemical disarmament and non-proliferation treaty.

Outcome after relapse of myelodysplastic syndrome and secondary acute myeloid leukemia following allogeneic stem cell transplantation: a retrospective registry analysis on 698 patients by the Chronic Malignancies Working Party of the European Society of Blood and Marrow Transplantation.

No standard exists for the treatment of myelodysplastic syndrome relapsing after allogeneic stem cell transplantation. We performed a retrospective registry analysis of outcomes and risk factors in 698 patients, treated with different strategies. The median overall survival from relapse was 4.7 months (95% confidence interval: 4.1-5.3) and the 2-year survival rate was 17.7% (95% confidence interval: 14.8-21.2%). Shorter remission after transplantation (P<0.001), advanced disease (P=0.001), older age (P=0.007), unrelated donor (P=0.008) and acute graft-versus-host disease before relapse (P<0.001) adversely influenced survival. At 6 months from relapse, patients had received no cellular treatment, (i.e. palliative chemotherapy or best supportive care, n=375), donor lymphocyte infusion (n=213), or a second transplant (n=110). Treatment groups were analyzed separately because of imbalanced characteristics and difficulties in retrospectively evaluating the reason for individual treatments. Of the patients who did not receive any cellular therapy, 109 were alive at 6 months after relapse, achieving a median overall survival from this landmark of 8.9 months (95% confidence interval: 5.1-12.6). Their 2-year survival rate was 29.7%. Recipients of donor lymphocytes achieved a median survival from first infusion of 6.0 months (95% confidence interval: 3.7-8.3) with a 2-year survival rate of 27.6%. Longer remission after first transplantation (P<0.001) and younger age (P=0.009) predicted better outcome. Among recipients of a second transplant, the median survival from second transplantation was 4.2 months (95% confidence interval: 2.5-5.9), and their 2-year survival rate was 17.0%. Longer remission after first transplantation (P<0.001), complete remission at second transplant (P=0.008), no prior chronic graft-versus-host disease (P<0.001) and change to a new donor (P=0.04) predicted better outcome. The data enabled identification of patients benefiting from donor lymphocyte infusion and second transplantation, and may serve as a baseline for prospective trials.

Prospective evaluation of the SeptiFAST multiplex real-time PCR assay for surveillance and diagnosis of infections in haematological patients after allogeneic stem cell transplantation compared to routine microbiological assays and an in-house real-time PCR method.

We prospectively evaluated a multiplex real-time PCR assay (SeptiFast, SF) in a cohort of patients undergoing allo-BMT in comparison to an in-house PCR method (IH-PCR). Overall 847 blood samples (mean 8 samples/patient) from 104 patients with haematological malignancies were analysed. The majority of patients had acute leukaemia (62%) with a mean age of 52 years (54% female). Pathogens could be detected in 91 of 847 (11%) samples by SF compared to 38 of 205 (18.5%) samples by BC, and 57 of 847 (6.7%) samples by IH-PCR. Coagulase-negative staphylococci (n=41 in SF, n=29 in BC) were the most frequently detected bacteria followed by Escherichia coli (n=9 in SF, n=6 in BC). Candida albicans (n=17 in SF, n=0 in BC, n=24 in IH-PCR) was the most frequently detected fungal pathogen. SF gave positive results in 5% of samples during surveillance vs in 26% of samples during fever episodes. Overall, the majority of blood samples gave negative results in both PCR methods resulting in 93% overall agreement resulting in a negative predictive value of 0.96 (95% CI: 0.95-0.97), and a positive predictive value of 0.10 (95% CI: -0.01 to 0.21). SeptiFast appeared to be superior over BC and the IH-PCR method.

Human leukocyte antigen-E mismatch is associated with better hematopoietic stem cell transplantation outcome in acute leukemia patients.

The immunomodulatory role of human leukocyte antigen (HLA)-E in hematopoietic stem cell transplantation (HSCT) has not been extensively investigated. To this end, we genotyped 509 10/10 HLA unrelated transplant pairs for HLA-E, in order to study the effect of HLA-E as a natural killer (NK)-alloreactivity mediator on HSCT outcome in an acute leukemia (AL) setting. Overall survival (OS), disease free survival (DFS), relapse incidence (RI) and non-relapse mortality (NRM) were set as endpoints. Analysis of our data revealed a significant correlation between HLA-E mismatch and improved HSCT outcome, as shown by both univariate (53% vs 38%, P=0.002, 5-year OS) and multivariate (hazard ratio (HR)=0.63, confidence interval (CI) 95%=0.48-0.83, P=0.001) analyses. Further subgroup analysis demonstrated that the positive effect of HLA-E mismatch was significant and pronounced in advanced disease patients (n=120) (5-year OS: 50% vs 18%, P=0.005; HR=0.40, CI 95%=0.22-0.72, P=0.002; results from univariate and multivariate analyses, respectively). The study herein is the first to report an association between HLA-E incompatibility and improved post-transplant prognosis in AL patients who have undergone matched unrelated HSCT. Combined NK and T cell HLA-E-mediated mechanisms may account for the better outcomes observed. Notwithstanding the necessity for in vitro and confirmational studies, our findings highlight the clinical relevance of HLA-E matching and strongly support prospective HLA-E screening upon donor selection for matched AL unrelated HSCTs.

Residual thymic tissue and lymph node involvement by acute myeloid leukaemia presenting as mediastinal, strongly 18 FDG-PET-positive masses.

We report on a multidisciplinary management of a 68-year-old AML patient presenting with a PET-positive mediastinal tumour typical for lymph node metastasis. It was removed via minimally invasive thoracoscopic intervention and was identified as a thymus residual infiltrated by AML. Follow-up PET-CT scan after resection and remission induction chemotherapy was completely normal. To our knowledge, this is the first documented case report of AML presenting with PET-positive infiltrates of thymic and lymph node tissue along the aortic bow mimicking a second intrathoracic malignancy. Our observation indicates the usefulness of this imaging technique and supports clarification of these unusual findings in AML patients, in case of need also by invasive diagnostic procedures, to enable an adequate therapeutic decision.

Long-term outcomes of allogeneic haematopoietic stem cell transplantation for adult cerebral X-linked adrenoleukodystrophy.

The adult cerebral inflammatory form of X-linked adrenoleukodystrophy is a rapidly progressive neurodegenerative disease, as devastating as childhood cerebral adrenoleukodystrophy. Allogeneic haematopoietic stem cell transplantation has been demonstrated to provide long-term neurological benefits for boys with the childhood cerebral form, but results in adults are sparse and inconclusive. We analysed data from 14 adult males with adult cerebral adrenoleukodystrophy treated with allogeneic haematopoietic stem cell transplantation on a compassionate basis in four European centres. All presented with cerebral demyelinating lesions and gadolinium enhancement. Median age at diagnosis of adult cerebral adrenoleukodystrophy was 33 years (range 21-48 years). In addition to cerebral inflammation, five patients had established severe motor disability from adrenomyeloneuropathy affecting only the spinal cord and peripheral nerves (Expanded Disability Status Scale score ≥ 6). Eight patients survived (estimated survival 57 ± 13%) with a median follow-up of 65 months (minimum 38 months). Death was directly transplant-/infection-related (n = 3), due to primary disease progression in advanced adult cerebral adrenoleukodystrophy (n = 1), or secondary disease progression (n = 2) after transient multi-organ failure or non-engraftment. Specific complications during stem cell transplantation included deterioration of motor and bladder functions (n = 12) as well as behavioural changes (n = 8). Arrest of progressive cerebral demyelination and prevention of severe loss of neurocognition was achieved in all eight survivors, but deterioration of motor function occurred in the majority (n = 5). Limited motor dysfunction (Expanded Disability Status Scale score < 6) prior to transplantation was associated with significantly improved survival [78 ± 14% (n = 9) versus 20 ± 18%(n = 5); P < 0.05] and maintenance of ambulation (Expanded Disability Status Scale score < 7) post-transplant (78% versus 0%; P = 0.021). In contrast, bilateral involvement of the internal capsule on brain MRI was associated with poorer survival [20 ± 18% (n = 5) versus 78 ± 14% (n = 9); P < 0.05]. This study is the first to support the feasibility, complications and potential long-term neurological benefit of allogeneic haematopoietic stem cell transplantation in adult cerebral adrenoleukodystrophy. Further studies are warranted to attempt to improve outcomes through patient selection and optimization of transplantation protocols.

Predictive significance of the European LeukemiaNet classification of genetic aberrations in patients with acute myeloid leukaemia undergoing allogeneic stem cell transplantation.

OBJECTIVES: The purpose of this study was to evaluate the predictive capacity of the European LeukemiaNet (ELN) classification of genetic risk in patients with acute myeloid leukaemia (AML) undergoing allogeneic stem cell transplantation (alloSCT). METHODS: We retrospectively analysed 274 patients transplanted at our centre between 2004 and 2014. RESULTS: The ELN grouping is comparable to the Southwest Oncology Group/Eastern Cooperative Oncology Group (SWOG/ECOG) stratification in predicting the outcome after alloSCT [overall P = 0.0064 for disease-free survival (DFS), overall P = 0.003 for relapse]. Patients with an intermediate-1 profile have a significantly elevated 5-yr relapse incidence as compared to favourable risk patients, that is 40% vs. 15%, [hazard ratio (HR) 2.58, P = 0.048]. An intermediate-1 risk profile is an independent predictor for relapse as determined by multivariate Cox regression analysis (HR 3.05, P = 0.023). In intermediate-1 patients, the presence of an FLT3 internal tandem duplication (FLT3-ITD) is associated with a significantly increased relapse incidence (P = 0.0323), and a lower DFS (P = 0.0465). FLT3-ITD is an independent predictor for overall survival, DFS and relapse incidence in the intermediate-1 subgroup. CONCLUSIONS: The ELN stratification of genetic risk predicts the outcome of patients with AML undergoing alloSCT. Patients with an intermediate-1 profile have a high risk for treatment failure due to relapse, which prompts the development of alternative treatment strategies.

Improving results of allogeneic hematopoietic cell transplantation for adults with acute lymphoblastic leukemia in first complete remission: an analysis from the Acute Leukemia Working Party of the European Society for Blood and Marrow Transplantation.

Allogeneic hematopoietic cell transplantation is widely used to treat adults with high-risk acute lymphoblastic leukemia. The aim of this study was to analyze whether the results changed over time and to identify prognostic factors. Adult patients treated between 1993 and 2012 with myeloablative allogeneic hematopoietic cell transplantation from HLA matched sibling (n=2681) or unrelated (n=2178) donors in first complete remission were included. For transplantations from sibling donors performed between 2008 and 2012, 2-year probabilities of overall survival were: 76% (18-25 years old), 69% (26-35 and 36-45 years old) and 60% (46-55 years old). Among recipients of transplantations from unrelated donors, the respective survival rates were 66%, 70%, 61%, and 62%. In comparison with the 1993-2007 period, significant improvements were observed for all age groups except for the 26-35-year old patients. In a multivariate model, transplantations performed between 2008 and 2012, when compared to 1993-2007, were associated with significantly reduced risks of non-relapse mortality (Hazard Ratio 0.77, P=0.00006), relapse (Hazard Ratio 0.85, P=0.007), treatment failure (Hazard Ratio 0.81, P<0.00001), and overall mortality (Hazard Ratio 0.79, P<0.00001). In the analysis restricted to transplantations performed between 2008 and 2012, the use of total body irradiation-based conditioning was associated with reduced risk of relapse (Hazard Ratio 0.48, P=0.004) and treatment failure (Hazard Ratio 0.63, P=0.02). We conclude that results of allogeneic hematopoietic cell transplantation for adults with acute lymphoblastic leukemia improved significantly over time. Total body irradiation should be considered as the preferable type of myeloablative conditioning.

Matching for the MICA-129 polymorphism is beneficial in unrelated hematopoietic stem cell transplantation.

Major histocompatibility complex class I polypeptide-related sequence A (MICA) is a highly polymorphic ligand of the activating NKG2D receptor on natural killer (NK) cells, γδ-T cells, and NKT cells. MICA incompatibilities have been associated with an increased graft-versus-host disease (GVHD) incidence, and the MICA-129 (met/val) dimorphism has been shown to influence NKG2D signaling in unrelated hematopoietic stem cell transplantation (uHSCT). We investigated the effect of MICA matching on survival after uHSCT. We sequenced 2172 patients and their respective donors for MICA. All patients and donors were high-resolution HLA-typed and matched for 10/10 (n = 1379), 9/10 (n = 636), or 8/10 (n = 157) HLA alleles. Within each HLA match group, cases matched and mismatched for MICA and MICA-129 were analyzed for the end points overall survival (OS), disease-free survival (DFS), nonrelapse mortality (NRM), relapse-incidence (RI), and GVHD. Mismatches at the MICA locus as well as MICA-129 increased with the number of HLA mismatches (MICA mismatched 10/10, 9.2% [n = 127]; 9/10, 22.3% [n = 142]; 8/10, 38.2% [n = 60]; MICA-129 mismatched 10/10, 3.9% [n = 54]; 9/10, 10.2% [n = 65]; 8/10, 17.2% [n = 27]). Adverse OS was observed in the 10/10 match group if MICA-129 was mismatched (10/10, hazard ratio [HR], 1.77; confidence interval [CI], 1.22-2.57; P = .003). MICA-129 mismatches correlated with a significantly worse outcome for DFS in the 10/10 HLA match group (HR, 1.77; CI, 1.26-2.50; P = .001). Higher rates of aGVHD were seen in MICA-129 mismatched cases. Our results indicate that MICA-129 matching is relevant in uHSCT. Prospective typing of patients and donors in unrelated donor search may identify mismatches for MICA-129, and compatible donor selection may improve outcome for this small but high-risk subgroup.