Abstract

While evidence for measurable residual disease (MRD) is a harbinger of inferior outcome in acute myeloid leukemia (AML) patients referred for allogeneic stem cell transplantation (allo-SCT), the exact clinical trajectory of specific patient subsets in this clinical setting is undefined. Using a recently published prognostic cytogenetic model (Leukemia 2019) we evaluated whether this model applied also to studies of patients with positive MRD. The analysis comprised MRD(+) patients in first complete remission undergoing allo-SCT from a matched sibling donor or unrelated donor. Seven hundred and seventy-five patients were evaluated with a median follow-up duration of 22 months. Cytogenetic risk score was favorable, intermediate/FLT3(wt) intermediate/FLT3-ITD, and adverse in 15%, 28.3%, 37% and 19.7% of the patients, respectively. Favorable and intermediate/FLT3(wt) risk patients had 2-year leukemia-free survival rates of 78% and 61%, respectively, compared with only 50% and 37% for intermediate FLT3-ITD and adverse risk patients, respectively (p<0.0001). In multivariate analysis adverse and intermediate/FLT3-ITD risk patients were more likely to experience disease relapse compared with favorable risk patients [Hazard ratio (HR)=3.9, 95% confidence interval (CI), 2.1-7.3; p<0.0001, and HR=4.4, CI 95%, 2.4-7.8; p<0.0001, respectively]. The EBMT cytogenetic risk score is a valuable adjunct for risk stratification of MRD(+) AML patients. This article is protected by copyright. All rights reserved.

Abstract

Graft-vs.-host disease (GvHD) is a major complication after allogeneic hematopoietic stem cell transplantation that causes mortality and severe morbidity. Genetic disparities in human leukocyte antigens between the recipient and donor are known contributors to the risk of the disease. However, the overall impact of genetic component is complex, and consistent findings across different populations and studies remain sparse. To gain a comprehensive understanding of the genes responsible for GvHD, we combined genome-wide association studies (GWAS) from two distinct populations with previously published gene expression studies on GvHD in a single gene-level meta-analysis. We hypothesized that genes driving GvHD should be associated in both data modalities and therefore could be detected more readily through their combined effects in the integrated analysis rather than in separate analyses. The meta-analysis yielded a total of 51 acute GvHD-associated genes (false detection rate [FDR] <0.1). In support of our hypothesis, this number was significantly higher than that in a permutation meta-analysis involving the whole data set, as well as in separate meta-analyses on the GWAS and gene expression data sets. The genes indicated by the meta-analysis were significantly enriched in 277 Gene Ontology terms (FDR < 0.05), such as T cell function and cytokine-mediated signaling pathways, and the results highlighted several established immune mediators, such as interleukins and JAK-STAT signaling, and presented TRAF6 and TERT as potential effector candidates. Altogether, the results support the chosen methodological approach, implicate a role of gene-level variation in donors' key immunological regulators predisposing patients to acute GVHD, and present potential targets for therapeutic intervention.

Abstract

Allogeneic hematopoietic stem cell transplantation (allo-HSCT) is curative for bone marrow failure in patients with Fanconi anemia (FA), but the presence of a malignant transformation is associated with a poor prognosis and the management of these patients is still challenging. We analyzed outcome of 74 FA patients with a diagnosis of myelodysplastic syndrome (n = 35), acute leukemia (n = 35) or with cytogenetic abnormalities (n = 4), who underwent allo-HSCT from 1999 to 2016 in EBMT network. Type of diagnosis, pre-HSCT cytoreductive therapies and related toxicities, disease status pre-HSCT, donor type, and conditioning regimen were considered as main variables potentially influencing outcome. The 5-year OS and EFS were 42% (30-53%) and 39% (27-51%), respectively. Patients transplanted in CR showed better OS compared with those transplanted in presence of an active malignant disease (OS:71%[48-95] vs 37% [24-50],P = .04), while none of the other variables considered had an impact. Twenty-two patients received pre-HSCT cytoreduction and 9/22 showed a grade 3-4 toxicity, without any lethal event or negative influence on survival after HSCT(OS:toxicity pre-HSCT 48% [20-75%] vs no-toxicity 51% [25-78%],P = .98). The cumulative incidence of day-100 grade II-IV a-GvHD and of 5-year c-GvHD were 38% (26-50%) and 40% (28-52%). Non-relapse-related mortality and incidence of relapse at 5-years were 40% (29-52%) and 21% (11-30%) respectively, without any significant impact of the tested variables. Causes of death were transplant-related events in most patients (34 out of the 42 deaths, 81%). This analysis confirms the poor outcome of transformed FA patients and identifies the importance of achieving CR pre-HSCT, suggesting that, in a newly diagnosed transformed FA patient, a cytoreductive approach pre-HSCT should be considered if a donor have been secured. This article is protected by copyright. All rights reserved.

Abstract

Following chemotherapy, secondary acute myeloid leukemia (sAML), occurring after antecedent hematologic diseases, previous chemotherapy or radiation, has an inferior prognosis compared with de novo AML. To define the outcome of sAML in the context of allogeneic stem cell transplantation (alloSCT), a retrospective, registry-based comparison was performed, including 11,439 patients with de novo and 1325 with sAML. Among transplants in first complete remission (CR1) (n = 8,600), the 3-year cumulative incidence of relapse (RI) and non-relapse mortality (NRM) was 28.5% and 16.4% for de novo, and 35% and 23.4% for sAML. Three-year overall survival (OS), leukemia-free survival (LFS) and Graft-versus-Host Disease/relapse-free survival (GRFS) was 60.8%, 55.1%, and 38.6% for de novo, and 46.7%, 41.6%, and 28.4% for sAML, respectively. In multivariate analysis, sAML was associated with a lower OS (HR = 1.33 [95% CI = 1.21-1.48]; p < 10(-5)), LFS (HR = 1.32 [95% CI = 1.19-1.45]; p < 10(-5)) and GRFS (HR = 1.2 [95% CI = 1.1-1.31]; p < 10(-4)) and higher NRM (HR = 1.37 [95% CI = 1.17-1.59]; p < 10(-4)) and RI (HR = 1.27 [95% CI = 1.12-1.44]; p < 10(-3)). Results of the Cox model were confirmed in a matched-pair analysis. In contrast, results did not differ between de novo and sAML after alloSCT in induction failure or relapse. Hence, this analysis identified sAML as an independent risk factor for outcome after alloSCT in CR1.

Abstract

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 >0.5 suggesting predictive ability). Median follow-up of the total cohort was 41 months (34-54 months) being different in post-PV (45 months) and post-ET myelofibrosis (38 months). Survival at one, two, and four years was 70% (63-77%), 61% (53- 69%) and 52% (43-61%) for the total cohort, 70% (59-80%), 61% (49-73%) and 51% (38-64%) for post-PV, and 71% (61-81%), 61% (50-72%) and 54% (42-66%) for post-ET myelofibrosis (p=0.78). Overall, the DIPSS was not significantly predictive of outcome (p=0.28). With respect to the MYSEC-PM, overall survival at four years was 69% for the low-risk, 55% for the intermediate-1-risk, 47% for the intermediate-2-risk, and 22% (0-45%) for the high-risk group. The prognostic model was predictive of survival overall (p=0.05) while groups with intermediate-2 and high risk showed no significant difference (p=0.44). Assessment of prognostic utility yielded C-index of 0.575 (0.502-0.648) for the DIPSS while assessment of the MYSEC-PM resulted in C-statistics of 0.636 (0.563-0.708) indicating improvement in prediction of posttransplant survival using the new MYSEC-PM. In addition, transplantations from an unrelated donor in comparison with an HLA-identical sibling showed worse outcome (p=0.04) and transplant recipients seropositive for cytomegalovirus in comparison with seronegative recipients (p=0.01) showed worse survival. In conclusion, incorporating transplant-specific as well as clinical and mutational information together with the MYSEC-PM may enhance risk stratification.

Abstract

Baseline cytogenetic studies at diagnosis remain the single most important determinant of outcome in patients with acute myeloid leukemia (AML). However, the prognostic role of the complete gamut of cytogenetic aberrations in AML patients undergoing allogeneic hematopoietic stem cell transplantation (allo-HSCT) is currently undefined. In addition, their significance in conjunction with FLT3-ITD status has not been addressed thus far. Using the ALWP/EBMT registry we conducted a retrospective analysis to determine the clinical outcomes of AML patients undergoing allo-HSCT with respect to specific recurring cytogenetic abnormalities complemented with FLT3-ITD status. We analyzed a cohort consisting of 8558 adult AML patients who underwent allo-HSCT from either a matched sibling or a matched unrelated donor. Patients with inv(3)(q21q26)/t(3;3)(q21;q26), del(5q), monosomy 7, chromosome 17p abnormalities, t(10;11)(p11-14;q13-23), t(6;11)(q27;q23), as well as those patients with a monosomal or complex karyotype experienced significantly inferior leukemia-free survival (LFS) compared to patients with a normal karyotype. Trisomy 14, del(9q), and loss of chromosome X were associated with improved LFS rates. A novel prognostic model delineating 5 distinct groups incorporating cytogenetic complexity and FLT3-ITD status was constructed with significant prognostic implications. Our analysis supports the added prognostic significance of FLT3-ITD to baseline cytogenetics in patients undergoing allo-HSCT.

Abstract

Most myelodysplastic syndromes (MDS)-patients receive multiple red blood cell transfusions (RBCT). Transfusions may cause iron-related toxicity and mortality, influencing outcome after allogeneic HSCT. This prospective non-interventional study evaluated 222 MDS and CMML patients undergoing HSCT. Overall survival (OS), relapse-free survival (RFS), non-relapse mortality (NRM), and relapse incidence (RI) at 36 months were 52%, 44%, 25%, and 31%, respectively. Age, percentage of marrow blasts and severe comorbidities impacted OS. RFS was significantly associated with RBCT burden prior to HSCT (HR: 1.7; p = .02). High ferritin levels had a significant negative impact on OS and RI, but no impact on NRM. Administration of iron chelation therapy prior to HSCT did not influence the outcome, but early iron reduction after HSCT (started before 6 months) improved RFS significantly after transplantation (56% in the control group vs. 90% in the treated group, respectively; p = .04). This study illustrates the impact of RBCT and related parameters on HSCT-outcome. Patients with an expected prolonged survival after transplantation may benefit from early iron reduction therapy after transplantation.

Abstract

INTRODUCTION Gonadal impairment is an important late effect having a significant impact on quality of life of transplanted patients. The aim of this study was to compare gonadal function after Busulfan (Bu) or Treosulfan (Treo) conditioning regimens in pre and post-pubertal children. MATERIAL AND METHODS This is a retrospective, multicenter study including children transplanted in pediatric European Society for Blood and Marrow Transplantation (EBMT) centers between 1992 and 2012 who did not receive gonadotoxic chemo-radiotherapy before the transplant. RESULTS We evaluated 137 patients transplanted in 25 pediatric EBMT centers. Median age at transplant was 11.04 years (range 5-18); 89 patients were males and 48 were females. Eighty-nine patients were pre-pubertal at transplant, while 48 were post-pubertal. One hundred eighteen children received Bu and 19 Treo. A higher proportion of females treated with Treo in pre-pubertal stage reached spontaneous puberty compared to those treated with Bu (p=0.02). Spontaneous menarche was more frequent after Treo than after Bu (p< 0.001). Post-pubertal males and females treated with Treo had significantly lower luteinizing hormone (LH) levels (p=0.03 and p=0.04, respectively) compared to the Bu group. CONCLUSIONS Frequency of gonadal damage associated with Treo was significantly lower than that observed after Bu. These results need to be confirmed in a larger population.

Abstract

Preliminary data suggest that allogeneic stem cell transplantation (allo-SCT) may be effective in T-prolymphocytic leukemia (T-PLL). The purpose of the present observational study was to assess the outcome of allo-SCT in patients aged 65 years or younger with a centrally confirmed diagnosis of T-PLL. Patients were consecutively registered with the EBMT at the time of transplantation and followed by routine EBMT monitoring but with an extended dataset. Between 2007 and 2012, 37 evaluable patients (median age 56 years) were accrued. Pre-treatment contained alemtuzumab in 95% of patients. Sixty-two percent were in complete remission (CR) at the time of allo-SCT. Conditioning contained total body irradiation with 6 Gy or more (TBI6) in 30% of patients. With a median follow-up of 50 months, the 4-year non-relapse mortality, relapse incidence, progression-free (PFS) and overall survival were 32, 38, 30 and 42%, respectively. By univariate analysis, TBI6 in the conditioning was the only significant predictor for a low relapse risk, and an interval between diagnosis and allo-SCT of more than 12 months was associated with a lower NRM. This study confirms for the first time prospectively that allo-SCT can provide long-term disease control in a sizable albeit limited proportion of patients with T-PLL.