Allogeneic hematopoietic cell transplantation is equally effective in secondary acute lymphoblastic leukemia (ALL) compared to de-novo ALL-a report from the EBMT registry

Secondary acute lymphoblastic leukemia (s-ALL) comprises up to 10% of ALL patients. However, data regarding s-ALL outcomes is limited. To answer what is the role of allogeneic hematopoietic cell transplantation (HCT) in s-ALL, a matched-pair analysis in a 1:2 ratio was conducted to compare outcomes between s-ALL and de novo ALL (dn-ALL) patients reported between 2000-2021 to the European Society for Blood and Marrow Transplantation registry. Among 9720 ALL patients, 351 (3.6%) were s-ALL, of which 80 were in first complete remission (CR1) with a known precedent primary diagnosis 58.8% solid tumor (ST), 41.2% hematological diseases (HD). The estimated 2-year relapse incidence (RI) was 19.1% (95%CI: 11-28.9), leukemia-free survival (LFS) 52.1% (95%CI: 39.6-63.2), non-relapse mortality (NRM) 28.8% (95%CI: 18.4-40), GvHD-free, relapse-free survival (GRFS) 39.4% (95%CI: 27.8-50.7), and overall survival (OS) 60.8% (95%CI: 47.9-71.4), and did not differ between ST and HD patients. In a matched-pair analysis, there was no difference in RI, GRFS, NRM, LFS, or OS between s-ALL and dn-ALL except for a higher incidence of chronic GvHD (51.9% vs. 31.4%) in s-ALL. To conclude, patients with s-ALL who received HCT in CR1 have comparable outcomes to patients with dn-ALL.

Metabolic syndrome and cardiovascular disease after haematopoietic cell transplantation (HCT) in adults: an EBMT cross-sectional non-interventional study

Metabolic syndrome (MetS) is associated with cardiovascular disease in the general population and is also a potential cardiovascular risk factor in survivors of haematopoietic cell transplantation (HCT). We report an EBMT cross-sectional, multi-centre, non-interventional study of 453 adult HCT patients surviving a minimum of 2 years post-transplant attending routine follow-up HCT and/or late effects clinics in 9 centres. The overall prevalence of MetS was 37.5% rising to 53% in patients >50 years of age at follow-up. There were no differences in rates of MetS between autologous and allogeneic HCT survivors, nor any association with graft-versus-host disease (GvHD) or current immunosuppressant therapy. Notably, there was a significantly higher occurrence of cardiovascular events (CVE, defined as cerebrovascular accident, coronary heart disease or peripheral vascular disease) in those with MetS than in those without MetS (26.7% versus 9%, p < 0.001, OR 3.69, 95% CI 2.09-6.54, p < 0.001), and, as expected, MetS and CVE were age-related. Unexpectedly, CVE were associated with occurrence of second malignancy. Screening for and management of MetS should be integrated within routine HCT long-term follow-up care for both allogeneic and autologous HCT survivors. Further research is warranted, including randomised controlled trials of interventional strategies and mechanistic studies of cardiovascular risk in HCT survivors.

Impact of patient: donor HLA disparity on reduced-intensity-conditioned allogeneic stem cell transplants from HLA mismatched unrelated donors for AML: from the ALWP of the EBMT

Patients with acute myeloid leukaemia (AML) who lack a matched sibling or unrelated donor commonly undergo transplantation from a donor matched at 9/10 HLA-A, -B, -C, -DRB1, -DQB1 alleles, and it is unclear if a specific locus mismatch is preferable to any other. We therefore studied 937 patients with AML in complete remission transplanted using a reduced intensity conditioning regimen from an unrelated donor mismatched at a single allele. In a multivariate analysis, patient age, adverse karyotype and patient cytomegalovirus (CMV) seropositivity were correlated with decreased leukaemia free survival (LFS) and overall survival (OS). There was no significant difference in LFS or OS between patients transplanted from donors mismatched at HLA-A, -B, -C or -DRB1 in comparison to a HLA-DQB1 mismatched transplant. In a multivariate analysis, patients transplanted with a HLA-A mismatched donor had higher rates of acute graft-versus-host disease (GVHD) and non-relapse mortality (NRM) than patients transplanted with a HLA-DQB1 mismatched donor. Patient CMV seropositivity was associated with an increase in NRM and acute GVHD and reduced LFS and OS, regardless of donor CMV status. For CMV seropositive patients lacking a fully matched donor, alternative GVHD and CMV prophylaxis strategies should be considered.

Postremission Consolidation by Autologous Hematopoietic Cell Transplantation (HCT) for Acute Myeloid Leukemia in First Complete Remission (CR) and Negative Implications for Subsequent Allogeneic HCT in Second CR: A Study by the Acute Leukemia Working Party of the European Society for Blood and Marrow Transplantation (EBMT)

After autologous hematopoietic cell transplantation (HCT) in the first complete remission (CR1), patients with acute myeloid leukemia (AML) may relapse and undergo allogeneic HCT in the second complete remission (CR2). The aim of this study was to analyze the outcome of allogeneic HCT performed in CR2 comparing patients with prior consolidation by autologous HCT versus patients with chemotherapy consolidation. Included were 2619 adults with allogeneic HCT in CR2 from 2000 to 2017 with (n = 417) or without (n = 2202) prior autologous HCT. Patient groups were not entirely comparable; patients with prior autologous HCT were younger, had less often a favorable cytogenetic profile, had more commonly donors other than matched siblings, and more often received reduced-intensity conditioning. In multivariate analysis, nonrelapse mortality risks in patients with prior autologous HCT were 1.34 (1.07 to 1.67; P = .01) after adjustment for age, cytogenetic risk, transplant year, donor, conditioning intensity, sex matching, interval diagnosis-relapse, and relapse-allogeneic HCT as compared with chemotherapy consolidation. Similarly, risks of events in leukemia-free survival and graft-versus-host disease, relapse-free survival were higher with prior autologous HCT, 1.17 (1.01 to 1.35), P = .03 and 1.18 (1.03 to 1.35), P = .02, respectively. Risk of death was also higher, 1.13 (0.97 to 1.32), P = .1, but this was not significant. Postremission consolidation with autologous HCT for AML in CR1 increases toxicity of subsequent allogeneic HCT in CR2.

Hematopoietic cell transplant nurse coordinators' perceptions of related donor care: a European survey from the EBMT Nurses Group

Allogeneic haematopoietic cell transplantation (HCT) is a curative procedure for patients with haematological malignancies and immune deficiencies. A human leukocyte antigen (HLA) identical sibling is only available for 25-35% of patients in need. The improvement in haplo-identical transplantation has led to a marked increase in cell donation from relatives. Despite international recommendations, discrepancies in related-donors (RD) care exist between centres, particularly regarding medical suitability criteria, consenting procedures and donor follow-up. This European survey aimed to explore hematopoietic cell transplantation coordinators nurses' (HCT-CNs) perceptions of RD care, in particular the association with the presence or not of an independent unit (IU). Ninety-three HCT-CNs from seventy-six EBMT centres responded, representing 19 countries (response rate: 27%). Our results did not show a significant association between IU and HCT-CNs perceptions of related-donors care. The practices for RD care vary among centres regarding presence or not of an IU (48%), person caring for RD (haematologist in 54%, HCT physician in 17%, HCT-CNs in 20%), person to whom the results of HLA typing are communicated, use of a booklet for RD, follow-up or not and periodicity of follow-up. Qualitative data highlight the related-donation ethical issues and the need for improvement in RD care. HCT-CNs' main concerns were: the necessary confidentiality to insure the voluntary status of RD, the perceived conflict of interest felt by professionals when managing both patients and RD, plus the psychosocial aspects of related-donation. Even if there is a variety of a practice among centres, the presence of an IU is not significantly associated with an improvement in RD care.

Trends in patient outcome over the past two decades following allogeneic stem cell transplantation for acute myeloid leukaemia: an ALWP/EBMT analysis

BACKGROUND

Outcomes for patients with acute myeloid leukaemia (AML) undergoing allogeneic stem cell transplantation (allo-SCT) have significantly improved in recent years.

OBJECTIVES

To assess the incremental improvement of transplanted AML patients in the last two decades.

METHODS

Patients included in this analysis were adult AML patients who underwent allo-SCT from an HLA-matched sibling donor (MSD) or HLA-matched unrelated donor (MUD) in first remission. Patient outcomes were assessed between three cohorts according to the year of transplant (1993-2002, 2003-2007 and 2008-2012).

RESULTS

The analysis comprised a total of 20 187 patients of whom 4763 were transplanted between 1993 and 2002, 5835 in 2003 and 2007, and 9589 in 2008 and 2012. In multivariate analysis, leukaemia-free survival (LFS) rates were significantly improved in more recently transplanted patients compared to patients transplanted in 1993-2002 [Hazard ratio (HR) = 0.84, confidence interval (CI) 95%, 0.77-0.92; P = 0.003], a benefit which also extended to improved overall survival (OS; HR = 0.8, CI 95%, 0.73-0.89; P < 0.0001), and decreased nonrelapse mortality (NRM) rates (HR = 0.65, CI 95%, 0.56-0.75; P < 0.0001). Subset analysis revealed that in MSD, the rates of LFS, NRM and OS significantly improved in patients in the more recent cohort with similar results also seen in MUD. Finally, the incidence of acute graft-versus-host disease (GVHD) was significantly reduced leading to improved GVHD-free/relapse-free survival (GRFS) rates in more recently transplanted patients.

CONCLUSION

Outcome of allo-SCT for AML patients has markedly improved in the last two decades owing to decreased nonrelapse mortality and improved rates of leukaemia-free survival resulting in significantly longer survival.

Cord blood transplantation is associated with good outcomes in secondary Acute Myeloid Leukaemia in first remission

BACKGROUND

We conducted a retrospective survey within the European Society for Blood and Marrow Transplantation (EBMT) registry to assess the outcomes of cord blood transplantation (CBT) in secondary acute myeloid leukaemia (sAML).

METHODS

Inclusion criteria consisted of ≥18 years of age, sAML, first CBT between 2002 and 2016, and either first complete remission (CR) or active disease at CBT.

RESULTS

One hundred forty-six patients met the study inclusion criteria. Status at transplantation was first CR (n = 97), primary refractory sAML (n = 30) or relapsed (n = 19) sAML. Neutrophil engraftment was achieved in 118 patients while the remaining 25 patients (17%) failed to engraft. This includes 13% of patients transplanted in first CR versus 30% of those transplanted with active disease (P = 0.008). Two-year incidences of relapse were 25% in first CR patients versus 36% in those with advanced disease (P = 0.06) while 2-year incidences of nonrelapse mortality were 35% and 49% (P = 0.03), respectively. At 2-year overall survival, leukaemia-free survival and graft-versus-host disease (GVHD)-free relapse-free survival were 42% vs. 19% (P < 0.001), 40% vs. 16% (P < 0.001), and 26% vs. 12% (P = 0.002) in first CR patients versus those with advanced disease, respectively.

CONCLUSIONS

We report here the first study of CBT in a large cohort of sAML patients. Main observation was that CBT rescued approximately 40% of patients with sAML in first CR.

Distinct factors determine the kinetics of disease relapse in adults transplanted for acute myeloid leukaemia

BACKGROUND

Disease recurrence remains the major cause of death in adults with acute myeloid leukaemia (AML) treated using either intensive chemotherapy (IC) or allogenic stem cell transplantation (allo-SCT).

AIMS

The timely delivery of maintenance drug or cellular therapies represent emerging strategies with the potential to reduce relapse after both treatment modalities, but whilst the determinants of overall relapse risk have been extensively characterized the factors determining the timing of disease recurrence have not been characterized.

MATERIALS AND METHODS

We have therefore examined, using a series of sequential landmark analyses, relapse kinetics in a cohort of 2028 patients who received an allo-SCT for AML in CR1 and separately 570 patients treated with IC alone.

RESULTS

In the first 3 months after allo-SCT, the factors associated with an increased risk of relapse included the presence of the FLT3-ITD (P < 0.001), patient age (P = 0.012), time interval from CR1 to transplant (P < 0.001) and donor type (P = 0.03). Relapse from 3 to 6 months was associated with a higher white cell count at diagnosis (P = 0.001), adverse-risk cytogenetics (P < 0.001), presence of FLT3-ITD mutation (P < 0.001) and time interval to achieve first complete remission (P = 0.013). Later relapse was associated with adverse cytogenetics, mutated NPM1, absence of chronic graft-versus-host disease (GVHD) and the use of in vivo T-cell depletion. In patients treated with IC alone, the factors associated with relapse in the first 3 months were adverse-risk cytogenetics (P < 0.001) and FLT3-ITD status (P = 0.001). The factors predicting later relapse were the time interval from diagnosis to CR1 (P = 0.22) and time interval from CR1 to IC (P = 0.012).

DISCUSSION AND CONCLUSION

Taken together, these data provide novel insights into the biology of disease recurrence after both allo-SCT and IC and have the potential to inform the design of novel maintenance strategies in both clinical settings.

Occurrence of graft-versus-host disease increases mortality after umbilical cord blood transplantation for acute myeloid leukaemia: a report from Eurocord and the ALWP of the EBMT

BACKGROUND

The efficacy of umbilical cord blood transplantation (UCBT) as treatment for acute myeloid leukaemia (AML) relies on immune-mediated graft-versus-leukaemia effects. Previous studies have suggested a strong association between graft-versus-host disease (GVHD) occurrence and graft-versus-leukaemia effects after allogeneic hematopoietic cell transplantation.

METHODS

Here, we evaluated the kinetics of relapse rate in correlation with GVHD occurrence after UCBT. The kinetics of relapse rate over time in correlation to GVHD occurrence were assessed by calculating the relapse rate per patient-year within sequential 90-day intervals. The impact of GVHD on relapse and mortality was further studied in multivariate Cox models handling GVHD as a time-dependent covariate.

RESULTS

The study included data from 1068 patients given single (n = 567) or double (n = 501) UCBT. The proportion of patients with grade II, III and IV acute GVHD was 20%, 7% and 4%, respectively. At 2 years, the cumulative incidence of chronic GVHD was 42%, the cumulative incidence of relapse was 32%, and overall survival was 32% as well. Relapse rates declined gradually over time during the first 30 months after transplantation. There was a possible suggestion that grade II-IV acute (HR = 0.8, P = 0.1) and chronic (HR = 0.65, P = 0.1) GVHD decreased relapse risk. However, grade II-IV acute GVHD significantly increased early (the first 18 months after UCBT) mortality (HR = 1.3, P = 0.02), whilst chronic GVHD increased each early (HR = 2.7, P < 0.001) and late (HR = 4.9, P < 0.001) mortality after UCBT.

CONCLUSIONS

The occurrence of grade II-IV acute or chronic GVHD each increases overall mortality after UCBT for AML mitigating the possible graft-versus-leukemia effect of GVHD.

What is the outcome in patients with acute leukaemia who survive severe acute graft-versus-host disease?

BACKGROUND

Acute graft-versus-host disease (aGVHD) is a major complication of allogeneic haematopoietic stem cell transplantation (HSCT). With new promising therapies, survival may improve for severe aGVHD.

OBJECTIVES

We wanted to analyze the long-term outcome in patients who survive severe aGVHD.

METHODS

This study was a landmark analysis of 23 567 patients with acute Leukaemia who survived for more than 6 months after HSCT, 2002-2014. Patients alive after severe aGVHD (n = 1738) were compared to controls.

RESULTS

Patients with severe aGVHD had higher non-relapse mortality (NRM) and higher rate of extensive chronic GVHD (cGVHD) than the controls (P < 10^-5 ). The probability of relapse was significantly lower in the severe aGVHD group, but Leukaemia-free survival (LFS) and overall survival were significantly lower than for the controls (P < 10^-5 ). Five-year LFS in patients with severe aGVHD was 49%, as opposed to 61% in controls with no or mild GVHD and 59% in patients with moderate GVHD.

CONCLUSIONS

HSCT patients who survive severe aGVHD have higher risk of developing extensive cGVHD, a higher NRM, a lower relapse probability, and lower LFS than other HSCT patients. This study is a platform for outcome analysis in patients treated with novel therapies for acute GVHD.

A comparison between allogeneic stem cell transplantation from unmanipulated haploidentical and unrelated donors in acute leukemia

BACKGROUND

In the absence of a HLA-matched related or matched unrelated donor, allogeneic stem cell transplantation (allo-SCT) from mismatched unrelated donors or haploidentical donors are potential alternatives for patients with acute leukemia with an indication to allo-SCT. The objective of this study was to compare the outcome of allo-SCT from T cell-replete haploidentical (Haplo) versus matched (MUD 10/10) or mismatched unrelated donor at a single HLA-locus (MMUD 9/10) for patients with acute leukemia in remission.

METHODS

Two hundred sixty-five adult patients with de novo acute leukemia in first or second remission that received a Haplo-SCT between January 2007 and December 2013 were compared with 2490 patients receiving a MUD 10/10 and 813 receiving a MMUD 9/10. Propensity score weighted analysis was conducted in order to control for disease risk imbalances between the groups.

RESULTS

The weighted 3-year non-relapse mortality and relapse incidence were 29 and 30% for Haplo, 21 and 29% for MUD 10/10, and 29 and 25% for MMUD 9/10, respectively. The weighted 3-year leukemia-free survival (LFS) and overall survival (OS) were 41 and 46% for Haplo, 50 and 56% for MUD 10/10, and 46 and 48% for MMUD 9/10, respectively. Using weighted Cox model, both LFS and OS were significantly higher in transplants from MUD 10/10 compared from those in Haplo but not different between transplants from MMUD 9/10 and Haplo. The type of donor was not significantly associated with neither acute nor chronic graft-versus-host disease.

CONCLUSIONS

Patients with acute leukemia in remission have better outcomes if transplanted from a MUD 10/10. We did not find any significant difference in outcome between transplants from MMUD 9/10 and Haplo, suggesting that both can be equally used in the absence of a 10/10 MUD. KEY POINT 1: Better outcomes using fully (10/10) matched unrelated donor for allo-SCT in acute leukemia in remission. KEY POINT 2: Similar outcomes after allo-SCT from unmanipulated haploidentical graft or mismatched (9/10) unrelated donor in acute leukemia in remission.

Safety and efficacy of thiotepa-based conditioning for allogeneic transplantation in AML: a survey from the ALWP of the EBMT

This study evaluated the safety and efficacy of thiotepa-based regimens before allogeneic stem cell transplantation in 310 adult patients with AML. Disease status at the time of transplantation was CR1 in 50%, CR2+ in 23.5% and advanced disease in 26.5%. Transplantation was performed from haploidentical (35%), matched sibling (27%), unrelated (20%) or cord blood (18%) donors. As for safety: mucositis occurred in 46.8% of the patients and the cumulative incidence (CI) of sinusoidal obstruction syndrome was 4.0%. With a median follow-up of 37 months, the CI of acute GvHD grade>II was 26.5%, whereas CI of chronic GvHD was 28.1% at 3 years. CI for non-relapse mortality at 3 years was 38.4%, 49.7% and 45.4% for patients in CR1, CR2+ and advanced disease, respectively (P=0.10). Relapse incidence at 3 years was 20.2, 30.7 and 40.6% in these three respective groups (P=0.002). CI for 3-year leukemia-free survival and overall survival were 41.4% and 45.6% (CR1), 19.6% and 27.7% (CR2+), and 13.9% and 13.6% (advanced disease), respectively (P<10^-4 for both). Our data suggest that thiotepa-based conditioning therapy in AML is feasible, effective and safe, as investigated for sinusoidal obstruction syndrome and mucositis.

Investigating covariate-by-centre interaction in survival data

In survival analysis, assessing the existence of potential centre effects on the baseline hazard or on the effect of fixed covariates on the baseline hazard, such as treatment-by-centre interaction, is a frequent clinical concern in multicentre studies. Survival models with random effects on the baseline hazard and/or on the effect of the covariates of interest have been largely applied, for instance, to investigate potential centre effects. We aimed to develop a procedure to routinely test for multiple random effects in survival analyses. We propose a statistic and a permutation approach to test whether all or a subset of components of the variance-covariance matrix of random effects are non-zero in a mixed-effects Cox model framework. Performances of the proposed permutation tests are examined under different null hypotheses corresponding to the different components of the variance-covariance matrix, i.e ., to the different random effects considered on the baseline hazard and/or on the covariates effects. Several alternative hypotheses are evaluated using simulations. The results indicate that the permutation tests have valid type I error rates under the null and achieve satisfactory power under all alternatives. The procedure is applied to two European cohorts of haematological stem cell transplants in acute leukaemia to investigate the heterogeneity across centres in leukaemia-free survival and the potential heterogeneity in prognostic factors effects across centres.

Does ex vivo CD34+ positive selection influence outcome after autologous hematopoietic stem cell transplantation in systemic sclerosis patients?

This EBMT Autoimmune Disease Working Party study aimed to evaluate the influence of CD34+ positive graft selection (CD34+) on the outcome of systemic sclerosis (SSc) patients after autologous hematopoietic stem cell transplantation (AHSCT). Clinical and laboratory data from 138 SSc patients at diagnosis, before and after AHSCT were retrospectively analyzed. CD34+ selection was performed in 47.1% (n=65) patients. By multivariate analysis adjusting for all factors differing between the two groups (without or with CD34+), there was no statistically significant difference in terms of overall survival (hazard ratio (HR): 0.98, 95% confidence interval (CI) 0.40-2.39, P=0.96), PFS (HR: 1.55, 95% CI 0.83-2.88, P=0.17) and incidence of relapse or progression (HR: 1.70, 95% CI 0.85-3.38, P=0.13). We demonstrate that CD34+ does not add benefit to the outcome of SSc patient treated with AHSCT. These findings should be further confirmed by prospective randomized trials.

Impact of conditioning with TBI in adult patients with T-cell ALL who receive a myeloablative allogeneic stem cell transplantation: a report from the acute leukemia working party of EBMT

Allogeneic hematopoietic stem cell transplantation (allo-SCT) is a therapeutic option for adult patients with T-cell ALL (T-ALL). Meanwhile, few allo-SCT data specific to adult T-ALL have been described thus far. Specifically, the optimal myeloablative conditioning regimen is unknown. In this retrospective study, 601 patients were included. Patients received allo-SCT in CR1, CR2, CR >2 or in advanced disease in 69%, 15%, 2% and 14% of cases, respectively. With an overall follow-up of 58 months, 523 patients received a TBI-based regimen, whereas 78 patients received a chemotherapy-based regimen including IV busulfan-cyclophosphamide (IV Bu-Cy) (n=46). Unlike patients aged ⩾35 years, patients aged <35 years who received a TBI-based regimen displayed an improved outcome compared with patients who received a chemotherapy-based regimen (5-year leukemia-free survival (LFS) of 50% for TBI versus 18% for chemo-only regimen or IV Bu-Cy regimens, P=10(-5) and 10(-4), respectively). In multivariate analysis, use of TBI was associated with an improved LFS (hazard ratio (HR)=0.55 (0.34-0.86), P=0.01) and overall survival (HR=0.54 (0.34-0.87), P=0.01) in patients aged <35 years. In conclusion, younger adult patients with T-ALL entitled to receive a myeloablative allo-SCT may benefit from TBI-based regimens.

Incidence and risk factors for hemorrhagic cystitis in unmanipulated haploidentical transplant recipients

BACKGROUND

Hemorrhagic cystitis (HC) is a common complication after hematopoietic allogeneic stem cell transplantation (HSCT) associated with intensity of the conditioning regimen, cyclophosphamide (Cy) therapy, and BK polyomavirus (BKPyV) infection.

METHODS

We analyzed 33 consecutive haploidentical (haplo) HSCT recipients transplanted for hematologic diseases. Eleven patients had a previous transplant. Median follow-up was 11 months. Graft-versus-host disease (GVHD) prophylaxis consisted of cyclosporine + mycophenolate mofetil and post-HSCT Cy.

RESULTS

Thirty-two of 33 patients achieved neutrophil recovery. Cumulative incidence (CI) of platelet recovery was 65%. CI grade II-IV acute GVHD was 44%. Twenty patients developed HC in a median time of 38 days. CI of HC at day 180 was 62%. BKPyV was positive in blood and urine of 91% of patients at HC onset. HC resolved in 18/20 patients. Factors associated with HC were previous transplant (P = 0.01) and occurrence of cytomegalovirus reactivation before HC (P = 0.05). Grade II-IV acute GVHD was not associated with HC (P = 0.62). CI of day 180 viral infections was 73%. Two-year overall survival (OS) was 50%; HC did not impact OS (P = 0.29).

CONCLUSION

The incidence of HC after haplo with post-HSCT Cy is high and is associated with morbidity, especially in high-risk patients such as those with a previous transplant history and with impaired immune reconstitution.

In patients older than 55 years with AML in first CR, should we search for a matched unrelated donor when an old sibling donor is available?

Allogeneic hematopoietic transplantation is increasingly used in patients aged 55 years or more with AML. The question of whether outcomes can be improved with an allele-level 8/8 HLA-matched unrelated donor (MUD) rather than an older HLA-matched sibling (MSD, more than 55 years) is still unanswered. We thus analyzed outcomes in 714 patients aged 55 years and older with AML in first CR (CR1) who received PBSCs after a reduced-intensity conditioning hematopoietic cell transplant from a MUD (n=310) or a MSD (n=404) in a recent period (2005-2010). The 3-year cumulative incidences (CIs) of non-relapse mortality were 17% and 23% with MSD and MUD, respectively (P=0.17). The 3-year CIs of relapse were 37% and 30%, respectively (P=0.12), resulting in a 3-year CI of leukemia-free survival of 46% and 47%, respectively (P=0.51). The 3-year overall survival was 49% with both MSD and MUD. In conclusion, HLA-identical sibling donors aged 55 years or more should not be excluded because of age for patients aged 55 years and older with AML in CR1.

Is there a stronger graft-versus-leukemia effect using HLA-haploidentical donors compared with HLA-identical siblings?

Haploidentical hematopoietic stem cell transplants (HSCTs) are increasingly used, but it is unknown whether they have a stronger graft-versus-leukemia (GVL) effect. We analyzed 10 679 acute leukemia patients who underwent HSCT from an HLA-matched sibling donor (MSD, n=9815) or a haploidentical donor (⩾2 HLA-antigen disparity, n=864) between 2007 and 2012, reported to the European Group for Blood and Marrow Transplantation. In a Cox regression model, acute and chronic graft-versus-host disease (GVHD) was added as time-dependent variables. There was no difference in probability of relapse between recipients of haploidentical and MSD grafts. Factors of importance for relapse after T-cell-replete grafts included remission status at HSCT, Karnofsky score ⩽80, acute GVHD of grade II or higher and chronic GVHD (P<10(-5)). Patients with post-transplant cyclophosphamide (n=194) had similar outcome as other T-cell-replete haploidentical transplants (n=369). Non-relapse mortality was significantly higher in the haploidentical group compared with that in MSD patients (P<10(-5)). Leukemia-free survival was superior in the MSD patients receiving T-cell-replete (P<10(-5)) or T-cell-depleted grafts (P=0.0006). The risk of relapse was the same in acute leukemia patients who received haploidentical donor grafts as in those given MSD transplants, suggesting a similar GVL effect.

Outcome of allogeneic hematopoietic stem-cell transplantation for adult patients with AML and 11q23/MLL rearrangement (MLL-r AML)

Acute myeloid leukemia (AML) with 11q23/MLL rearrangement (MLL-r AML) is allocated to the intermediate- or high-risk cytogenetic prognostic category depending on the MLL fusion partner. A more favorable outcome has been reported in patients receiving an allogeneic hematopoietic stem-cell transplantation (alloHSCT), but this has not been confirmed in large series. We analyzed the outcome of alloHSCT among adult patients reported to the Acute Leukemia Working Party between 2000 and 2010. We identified 159 patients with 11q23/MLL rearranged AML allografted in first complete remission (CR1, n=138) or CR2, mostly corresponding to t(9;11), t(11;19), t(6;11) and t(10;11) translocations. Two-year overall survival (OS), leukemia-free survival (LFS), relapse incidence and non-relapse mortality were 56±4%, 51±4%, 31±3% and 17±4%, respectively. The outcome differed according to 11q23/MLL rearrangement, being more favorable in patients with t(9;11) and t(11;19) compared with t(10;11) and t(6;11) (2-year OS: 64±6% and 73±10% vs 40±13% and 24±11%, respectively; P<0.0001). Multivariate analysis for OS identified t(6;11), t(10;11), age>40 years and CR2 as unfavorable features, whereas t(6;11), t(10;11), CR2 and the use of reduced-intensity conditioning regimen affected poorly the LFS. This study confirms the potential role of alloHSCT for adult patients with 11q23/MLL rearranged AML in CR1.

Increased incidence of chronic GvHD and CMV disease in patients with vitamin D deficiency before allogeneic stem cell transplantation

Vitamin D has emerged as a central player in the immune system, with its deficiency being implicated in the pathogenesis of several autoimmune diseases, including chronic GvHD. This is a retrospective cohort analysis of 166 patients, who underwent allogeneic hematopoietic stem cell transplantation (HSCT) at the Karolinska University Hospital, evaluating GvHD, graft failure, infectious complications and survival after HSCT in relation to pre-transplantation vitamin D levels. Most of the patients were deficient in vitamin D before HSCT (median 42 nmol/L). In multivariate analysis, vitamin D level before HSCT was identified as a significant independent risk factor for development of cGvHD. The increased incidence of cGvHD was not coupled to better disease-free survival; instead there was a trend towards lower overall survival in the vitamin D-deficient patients. In addition, we found a significant correlation between vitamin D deficiency and incidence of CMV disease, with no case of CMV disease occurring in patients with sufficient levels of vitamin D before HSCT. Our results support a role of vitamin D in immune tolerance following HSCT. These findings could be highly relevant for the care of HSCT patients, and prospective, randomized studies on the effect of vitamin D supplementation are therefore needed.

Comparison of outcomes after unrelated cord blood and unmanipulated haploidentical stem cell transplantation in adults with acute leukemia

Outcomes after unmanipulated haploidentical stem cell transplantation (Haplo) and after unrelated cord blood transplantation (UCBT) are encouraging and have become alternative options to treat patients with high-risk acute leukemia without human leukocyte antigen (HLA) matched donor. We compared outcomes after UCBT and Haplo in adults with de novo acute myeloid leukemia (AML) and acute lymphoblastic leukemia (ALL). Median follow-up was 24 months. Analysis was performed separately for patients with AML, n=918 (Haplo=360, UCBT=558) and ALL, n=528 (Haplo=158 and UCBT=370). UCBT was associated with delayed engraftment and higher graft failure in both AML and ALL recipients. In multivariate analysis, UCBT was associated with lower incidence of chronic graft-vs-host disease both in the AML group (hazard ratio (HR)=0.63, P=0.008) and in the ALL group (HR=0.58, P=0.01). Not statistically significant differences were observed between Haplo and UCBT for relapse incidence (HR=0.95, P=0.76 for AML and HR=0.82, P=0.31 for ALL), non-relapse mortality (HR=1.16, P=0.47 for AML and HR=1.23, P=0.23 for ALL) and leukemia-free survival (HR 0.78, P=0.78 for AML and HR=1.00, P=0.84 for ALL). There were no statistically differences on main outcomes after unmanipulated Haplo and UCBT, and both approaches are valid for acute leukemia patients lacking a HLA matched donor. Both strategies expand the donor pool for patients in need.

Allogeneic hematopoietic stem cell transplantation in solid organ transplant recipients: a retrospective, multicenter study of the EBMT

We conducted a questionnaire survey of the 565 European Society for Blood and Marrow Transplantation centers to analyze the outcome of allogeneic hematopoietic stem cell transplantation (alloSCT) in recipients of solid organ transplantation (SOT). We investigated 28 patients with malignant (N = 22) or nonmalignant diseases (N = 6), who underwent 31 alloSCT procedures: 12 after kidney, 13 after liver and 3 after heart transplantation. The incidence of solid organ graft failure at 60 months after first alloSCT was 33% (95% confidence interval [CI], 16-51%) for all patients, 15% (95% CI, 2-40%) for liver recipients and 50% (95% CI, 19-75%) for kidney recipients (p = 0.06). The relapse rate after alloSCT (22%) was low following transplantation for malignant disorders, despite advanced stages of malignancy. Overall survival at 60 months after first alloSCT was 40% (95% CI, 19-60%) for all patients, 51% (95% CI, 16-86%) for liver recipients and 42% (95% CI, 14-70%) for kidney recipients (p = 0.39). In summary, we show that selected SOT recipients suffering from hematologic disorders may benefit from alloSCT and experience enhanced long-term survival without loss of organ function.

A survey on unmanipulated haploidentical hematopoietic stem cell transplantation in adults with acute leukemia

The use of unmanipulated graft is increasingly adopted in the setting of allogeneic hematopoietic stem cell transplantation from haploidentical family donors (haplo-SCT) in acute leukemia (AL). We analyzed the outcome of 229 adult patients with de novo AL, who received an unmanipulated haploidentical transplant as their first allo-SCT between 2007 and 2011. Median follow-up was 30 months. Disease status at transplant was: first complete remission (CR1) for 77, second CR (CR2) for 56, and advanced for 96 patients. One hundred and seventy-one patients received in vivo T-cell depletion by monoclonal antibodies (75%). The 60-day cumulative incidence (CI) of engraftment was 93±2%. The 100-day CI of acute graft-versus-host disease (GvHD) was 32±3% for grade II-IV, 12±3% for grade III-IV. The 3-year CI of chronic GvHD was 34±3%. The 3-year CI of non-relapse mortality was 31±4% with in vivo T-cell depletion and 17±5% without. At 3 years, for patients transplanted in CR1, CR2 or advanced disease leukemia-free survival was 44±6, 42±7 and 12±3%, overall survival was 55±6, 51±7 and 14±4% and CI of relapse was 32±6, 24±6 and 61±5%, respectively. These data suggest that unmanipulated haplo-SCT is a valid treatment option for adult AL patients in complete remission lacking a matched donor.

Comparing i.v. BU dose intensity between two regimens (FB2 vs FB4) for allogeneic HCT for AML in CR1: a report from the Acute Leukemia Working Party of EBMT

This retrospective analysis compared two regimens of fludarabine combined with i.v. BU 6.4 mg/kg (FB2) or BU 12.8 mg/kg (FB4) for allografting of AML in first CR. A total of 437 patients (median age: 50 years) were administered FB2 (n = 225, 51%) or FB4 (n = 212, 49%). Median follow-up time was 28 months. Use of FB2 resulted in a longer time to neutrophil engraftment (17 vs 15 days, P < 0.0001) but no difference in incidence of grade II-IV acute (P = 0.54) or chronic GVHD (P = 0.51). In patients < 50 years of age, FB2 was associated with a higher 2-year cumulative incidence of relapse (33 ± 6% vs 20 ± 4%, P = 0.04), but there was no difference in 2-year leukemia-free survival (LFS) (P = 0.45), OS (P = 0.53) or non-relapse mortality (P = 0.17). In recipients ⩾ 50 years of age, FB2 resulted in better 2-year LFS (63 ± 4% vs 42 ± 7%, P = 0.02) and OS (68 ± 4% vs 45 ± 7%, P = 0.006); a lower 2-year non-relapse mortality, albeit not statistically significant (15 ± 3% vs 29 ± 6%, P = 0.06), was observed with FB2. FB2 is an effective and well-tolerated regimen in patients ⩾ 50 years of age and does not compromise survival when used in patients <50 years undergoing allogeneic transplantation for AML in first CR.

Prediction of non-relapse mortality in recipients of reduced intensity conditioning allogeneic stem cell transplantation with AML in first complete remission

Non-relapse mortality (NRM) after allogeneic hematopoietic stem cell transplantation (alloHSCT) can be predicted by the hematopoietic cell transplantation comorbidity index (HCT-CI) and the European Group for Blood and Marrow Transplantation (EBMT) score, which are composed of different parameters. We set out to integrate the parameters of both scores in patients with acute myeloid leukemia (AML) in first complete remission (CR1) receiving reduced intensity conditioning (RIC) alloHSCT. All parameters from the HCT-CI and the EBMT-score with the addition of patient and donor cytomegalovirus serology were evaluated in 812 patients by multivariable analysis with end-point NRM at 2 years. Subsequently, 16 parameters were selected based on hazard ratio >1.2, and were incorporated into a novel score, which was further internally validated by bootstrapping. Both the HCT-CI and the EBMT-score showed relatively weak predictive value, whereas the integrated score allowed to identify three clearly distinct risk groups with 2-year NRM estimates of 8±2% (low-risk), 17±2% (intermediate-risk) and 38±4% (high-risk), which also translated in prediction of overall survival. Collectively, integration of the most dominant parameters from the HCT-CI and the EBMT-score allowed to develop a simple and robust, integrated score with improved prediction of NRM for AML patients proceeding to RIC alloHSCT in CR1.

Use of G-CSF to hasten neutrophil recovery after auto-SCT for AML is not associated with increased relapse incidence: a report from the Acute Leukemia Working Party of the EBMT

Application of G-CSF in AML is controversial as leukemic blasts may express receptors interacting with the cytokine, which may stimulate leukemia growth. We retrospectively analyzed the impact of G-CSF use to accelerate neutrophil recovery after auto-SCT on outcome. Adults with AML in first CR autografted between 1994 and 2010 were included. Nine hundred and seventy two patients were treated with G-CSF after auto-SCT whereas 1121 were not. BM and PB were used as a source of stem cells in 454 (22%) and 1639 (78%) cases, respectively. The incidence of relapse at 5 years in the BM-auto-SCT group was 38% for patients receiving post-transplant G-CSF and 43% for those not treated with G-CSF, P=0.46. In the PB-auto-SCT cohort, respective probabilities were 48% and 49%, P=0.49. No impact of the use of G-CSF could be demonstrated with respect to the probability of leukemia-free survival: in the BM-auto-SCT group, 51% for G-CSF(+) and 48% for G-CSF(-), P=0.73; in PB-auto-SCT group, 42% for G-CSF(+) and 43% for G-CSF(-), P=0.83. Although G-CSF administration significantly shortened the neutropenic phase, no beneficial effect was observed with regard to non-relapse mortality. In patients with AML, the use of G-CSF after auto-SCT is not associated with increased risk of relapse irrespective of the source of stem cells used.

Allogeneic hematopoietic SCT for adults AML using i.v. BU in the conditioning regimen: outcomes and risk factors for the occurrence of hepatic sinusoidal obstructive syndrome

I.v. BU is frequently used in the conditioning regimen prior to allogeneic hematopoietic SCT (allo-HSCT); however, overall outcomes, incidence of hepatic sinusoidal obstructive syndrome (SOS) and its risk factors are not well known. With this aim, we performed a study on 257 AML adult recipients. Seattle Criteria were used for diagnosis and classification of SOS. The median age was 44 years. Donors were HLA-identical siblings in 60%, HLA-matched unrelated in 29% and HLA mismatched in 11%. Conditioning regimen was myeloablative in 84% (i.v. BU with CY was the most frequently used regimen) and it was reduced intensity in 16% (i.v. BU associated with fludarabine). Acute and chronic GVHD was observed in 28% and 44%, respectively. Two-year incidence of non-relapse mortality was 16±2% and 2-year leukemia-free survival for patients in CR1, CR2 and non remission at HSCT were 55±4%, 58±7%, and 20±5%, respectively. At 6 months, incidence of SOS was 7.8±2%; and it was severe in eight patients (3%). Factors associated with the occurrence of SOS were: HLA-mismatched donor HSCT (P=0.002) and patients transplanted in non-remission (P=0.002). In conclusion, outcomes of HSCT using i.v. BU are encouraging in this setting, SOS incidence is low and it is influenced by the type of donor and disease status at the time of transplant.

Impact of in vivo T-cell depletion on outcome of AML patients in first CR given peripheral blood stem cells and reduced-intensity conditioning allo-SCT from a HLA-identical sibling donor: a report from the Acute Leukemia Working Party of the European Group for Blood and Marrow Transplantation

The impact of in vivo T-cell depletion on transplantation outcomes in patients transplanted with reduced-intensity conditioning (RIC) remains controversial. This study assessed the outcome of 1250 adult patients with de novo AML in first CR (CR1) given PBSC from HLA-identical siblings after chemotherapy-based RIC. A total of 554 patients did not receive any form of in vivo T-cell depletion (control group), whereas antithymocyte globulin (ATG) and alemtuzumab were given in 444 and 252 patients, respectively. The incidences of grade II-IV acute GVHD were 21.4, 17.6 and 10.2% in control, ATG and alemtuzumab patients, respectively (P<0.001). In multivariate analysis, the use of ATG and the use of alemtuzumab were each associated with a lower risk of chronic GVHD (P<0.001 each), but a similar risk of relapse, and of nonrelapse mortality, and similar leukemia-free survival and OS. Further, among patients given BU-based RIC, the use of <6 mg/kg ATG did not increase the risk of relapse (hazard ratio, HR=1.1), whereas there was a suggestion for higher relapse risk in patients given 6 mg/kg ATG (HR=1.4, P=0.08). In summary, these data suggest that a certain amount of in vivo T-cell depletion can be safely used in the conditioning of AML patients in CR1 given PBSC after chemotherapy-based RIC.

Comparison of outcomes after single or double cord blood transplantation in adults with acute leukemia using different types of myeloablative conditioning regimen, a retrospective study on behalf of Eurocord and the Acute Leukemia Working Party of EBMT

We report outcomes after single (s) and double (d) umbilical cord blood transplantation (UCBT) after myeloablative conditioning (MAC) regimen for 239 patients transplanted for acute leukemia in first complete remission (CR1). All sUCBT patients received a total nucleated cell dose >2.5 × 10(7)/kg. Conditioning regimen for sUCBT was total body irradiation (TBI)12 Gy- or busulfan (BU)-based ± fludarabine (Flu) (n=68, group 1), thiotepa+BU+Flu (TBF) (n=88, group 2), and for dUCBT it was TBI12 Gy+cyclophosphamide ± Flu (n=83, group 3). dUCBT recipients were younger, received higher cell dose and less frequently antithymocyte globulin. In multivariate analysis, we found similar neutrophil recovery among the three groups; however, acute graft-versus-host disease II-IV was higher in dUCBT compared with others. Non-relapse mortality and relapse incidence were not statistically different among the three groups. Leukemia-free survival was 30% for sUCBT using TBI- or BU-based MAC compared with 48% for sUCBT TBF and 48% for dUCBT (P=0.02 and P=0.03, respectively), and it was not statistically different between sUCBT with TBF and dUCBT. In conclusion, use of sUCBT with adequate cell dose (>2.5 × 10(7)/kg) and a specific conditioning regimen in the MAC setting results in similar outcomes as dUCBT. The choice of TBF conditioning regimen for sUCBT may improve results, and whether this regimen may be effective in dUCBT should be further analyzed.

Autologous haematopoietic stem cell transplantation for systemic lupus erythematosus: data from the European Group for Blood and Marrow Transplantation registry

OBJECTIVES

Patients with systemic lupus erythematosus (SLE) refractory to conventional immunosuppression suffer substantial morbidity and mortality due to active disease and treatment toxicity. Immunoablation followed by autologous stem cell transplantation (ASCT) is a novel therapeutic strategy that potentially offers new hope to these patients.

METHODS

This retrospective survey reviews the efficacy and safety of ASCT in 28 SLE patients from eight centres reported to the European Group for Blood and Marrow Transplantation (EBMT) registry between 2001 and 2008.

RESULTS

Median disease duration before ASCT was 52 (nine to 396) months, 25/28 SLE patients (89%) were female, age 29 (16-48) years. At the time of ASCT, eight (one to 11) American College of Rheumatology (ACR) diagnostic criteria for SLE were present and 17 (60%) patients had nephritis. Peripheral blood stem cells were mobilized with cyclophosphamide and granulocyte-colony stimulating factor in 93% of patients, and ex vivo CD34 stem cell selection was performed in 36%. Conditioning regimens were employed with either low (n = 10) or intermediate (18) intensities. With a median follow-up of 38 (one to 110) months after ASCT, the five-year overall survival was 81 ± 8%, disease-free survival was 29 ± 9%, relapse incidence (RI) was 56 ± 11% and non-relapse mortality was 15 ± 7%. Graft manipulation by CD34+ selection was associated with a lower RI (p = 0.001) on univariate analysis. There were five deaths within two years after ASCT: three caused by infection, one by secondary autoimmune disease and one by progressive SLE.

CONCLUSIONS

Our data further support the concept of immunoablation and ASCT to re-induce long-term clinical and serologic remissions in refractory SLE patients even in the absence of maintenance therapy. This study also suggests a beneficial effect of ex vivo graft manipulation on prevention of relapses post-transplantation in SLE.

Bone marrow or peripheral blood stem cell transplantation from unrelated donors in adult patients with acute myeloid leukaemia, an Acute Leukaemia Working Party analysis in 2262 patients

BACKGROUND

No survival benefit of using blood stem cells instead of bone marrow (BM) has been shown in matched unrelated donor (MUD) transplantation.

DESIGN AND METHODS

In a retrospective registry analysis, we compared the use of blood stem cells (n = 1502) and BM (n = 760) from unrelated donors in patients aged 18-60 years with acute myeloid leukaemia (AML) undergoing myeloablative conditioning between 1997 and 2008. The blood stem cell recipients were older (P < 0.01), had more advanced disease (P < 0.0001) and received less total body irradiation (P < 0.0001) and more antithymocyte globulin (P = 0.01).

RESULTS

Recovery of neutrophils and platelets was faster with blood stem cells (P < 0.0001). The incidence of acute graft-versus-host disease (GVHD) was similar, but there was more chronic GVHD in the blood stem cell group [hazard ratio (HR) = 1.29, P = 0.02]. There were no significant differences in nonrelapse mortality (NRM), relapse incidence and leukaemia-free survival (LFS) between the two groups amongst patients with AML in remission. In patients with advanced leukaemia, NRM was lower (HR = 0.61, P = 0.02) and LFS was prolonged (HR = 0.67, P = 0.002) when blood stem cells were used. At 3 years, LFS for all patients, regardless of remission status, was 41% for both treatment groups. The outcome was not affected after multivariable analysis adjusted for confounders.

CONCLUSION

Blood stem cells compared with BM in MUD transplantation for patients with AML in remission resulted in the same rates of LFS. In patients with advanced leukaemia, the blood stem cell group had reduced NRM and improved LFS.

The impact of center experience on results of reduced intensity: allogeneic hematopoietic SCT for AML. An analysis from the Acute Leukemia Working Party of the EBMT

Allogeneic hematopoietic SCT with reduced-intensity conditioning (RIC-HSCT) is increasingly adopted for the treatment of older adults with AML. Our goal was to verify for the first time, if center experience influences outcome of RIC-HSCT. Results of 1413 transplantations from HLA-matched related or unrelated donors for adult patients with AML in first CR were analyzed according to the level of center activity. Transplants were performed in 203 European centers between 2001 and 2007. The 2-year probability of leukemia-free survival (LFS) after RIC-HSCT performed in centers with the lowest activity (< or =15 procedures/7 years) was 43±3% compared with 55±2% in the remainder (P<0.001). The incidence of non-relapse mortality (NRM) was 24±3% and 15±1% (P=0.004), whilst relapse rate was 33±3% and 31±1% (P=0.33), respectively. In a multivariate model, adjusted for other prognostic factors, low RIC-HSCT activity was associated with decreased chance of LFS (hazard ratio (HR)=0.64; P<0.001) and increased risk of NRM (HR=1.47, P=0.04) and relapse (HR=1.41, P=0.01). Center experience is a very important predictor of outcome and should be considered in future analyses evaluating the results of RIC-HSCT. The reasons why centers with low RIC-HSCT activity have worse outcomes should be further investigated.

Haematopoietic SCT in severe autoimmune diseases: updated guidelines of the European Group for Blood and Marrow Transplantation

In 1997, the first consensus guidelines for haematopoietic SCT (HSCT) in autoimmune diseases (ADs) were published, while an international coordinated clinical programme was launched. These guidelines provided broad principles for the field over the following decade and were accompanied by comprehensive data collection in the European Group for Blood and Marrow Transplantation (EBMT) AD Registry. Subsequently, retrospective analyses and prospective phase I/II studies generated evidence to support the feasibility, safety and efficacy of HSCT in several types of severe, treatment-resistant ADs, which became the basis for larger-scale phase II and III studies. In parallel, there has also been an era of immense progress in biological therapy in ADs. The aim of this document is to provide revised and updated guidelines for both the current application and future development of HSCT in ADs in relation to the benefits, risks and health economic considerations of other modern treatments. Patient safety considerations are central to guidance on patient selection and HSCT procedural aspects within appropriately experienced and Joint Accreditation Committee of International Society for Cellular Therapy and EBMT accredited centres. A need for prospective interventional and non-interventional studies, where feasible, along with systematic data reporting, in accordance with EBMT policies and procedures, is emphasized.

Impact of graft-versus-host disease after reduced-intensity conditioning allogeneic stem cell transplantation for acute myeloid leukemia: a report from the Acute Leukemia Working Party of the European group for blood and marrow transplantation

This report investigated the impact of graft-versus-host disease (GVHD) on transplantation outcomes in 1859 acute myeloid leukemia patients given allogeneic peripheral blood stem cells after reduced-intensity conditioning (RIC allo-SCT). Grade I acute GVHD was associated with a lower risk of relapse (hazards ratio (HR)=0.7, P=0.02) translating into a trend for better overall survival (OS; HR=1.3; P=0.07). Grade II acute GVHD had no net impact on OS, while grade III-IV acute GVHD was associated with a worse OS (HR=0.4, P<0.0.001) owing to high risk of nonrelapse mortality (NRM; HR=5.2, P<0.0001). In time-dependent multivariate Cox analyses, limited chronic GVHD tended to be associated with a lower risk of relapse (HR=0.72; P=0.07) translating into a better OS (HR=1.8; P<0.001), while extensive chronic GVHD was associated with a lower risk of relapse (HR=0.65; P=0.02) but also with higher NRM (HR=3.5; P<0.001) and thus had no net impact on OS. In-vivo T-cell depletion with antithymocyte globulin (ATG) or alemtuzumab was successful at preventing extensive chronic GVHD (P<0.001), but without improving OS for ATG and even with worsening OS for alemtuzumab (HR=0.65; P=0.001). These results highlight the role of the immune-mediated graft-versus-leukemia effect in the RIC allo-SCT setting, but also the need for improving the prevention and treatment of severe GVHD.

Outcomes and prognostic factors of adults with acute lymphoblastic leukemia who relapse after allogeneic hematopoietic cell transplantation. An analysis on behalf of the Acute Leukemia Working Party of EBMT

To describe outcomes, treatment and prognostic factors that influence survival of adult patients with acute lymphoblastic leukemia (ALL), who relapsed after allogeneic hematopoietic cell transplantation (HCT), we retrospectively analyzed 465 ALL adult patients from European Group for Blood and Marrow Transplantation (EBMT) centers who relapsed after a first HCT performed in complete remission (CR1 65%, CR2/3 35%). Salvage treatments were: supportive care (13%), cytoreductive therapy (43%), donor lymphocyte infusion without or with prior chemotherapy (23%) and second HCT (20%). Median time from HCT to relapse was 6.9 months, median follow-up was 46 months and median survival after relapse was 5.5 months. Estimated 1-, 2- and 5-year post-relapse survival was 30 ± 2%, 16 ± 2% and 8 ± 1%, respectively. In a multivariate analysis, adverse factors for survival were: late CR (CR2/3) at transplant (P<0.012), early relapse after transplant (<6.9 months, P <0.0001) and peripheral blast percent at relapse (P <0.0001). On the basis of multivariate model for survival, three groups of patients were identified with estimated 2 year survival of 6 ± 2, 17 ± 3 and 30 ± 7%. Outcome of ALL patients relapsing after HCT is dismal and there is a need for new therapies. Our study provides the standard expectations in ALL relapse and may help in the decision of post-relapse therapy.

A new Leukemia Prognostic Scoring System for refractory/relapsed adult acute myelogeneous leukaemia patients: a GOELAMS study

A simplified prognostic score is presented based on the multivariate analysis of 138 refractory/relapsed acute myeloid leukaemia (AML) patients (median age 55 years, range: 19-70) receiving a combination of intensive chemotherapy+Gemtuzumab as salvage regimen. Overall, 2-year event-free survival (EFS) and overall survival (OS) were 29±4% and 36±4%, respectively. Disease status (relapse <12 months, including refractory patients), FLT3-ITD-positive status and high-risk cytogenetics were the three strongest independent adverse prognostic factors for OS and EFS in this series. We then defined three subgroups with striking different outcomes at 2 years: no adverse factor (favourable, N=36): OS 58%, EFS 45%; one adverse factor (intermediate, N=54): OS 37%, EFS 31%; two or three adverse factors (poor, N=43): OS 12%, EFS 12% (P<10(-4), P=0.001). This new simplified Leukemia Prognostic Scoring System was then validated on an independent cohort of 111 refractory/relapsed AML patients. This new simplified prognostic score, using three clinical and biological parameters routinely applied, allow to discriminate around two third of the patients who should benefit from a salvage intensive regimen in the setting of refractory/relapsed AML patients. The other one third of the patients should receive investigational therapy.