European LeukemiaNet Risk Research Articles

Re-Examination of 2017 ELN Risk Classification By a Cohort of 739 De Novo aml Patients in Taiwan: Co-Occurring Poor-Risk Mutations May Further Predict Outcome in FLT3-ITD Patients

IntroductionRecent advances in the discovery of the genomic landscape in AML prompts necessity to re-examine the 2017 European LeukemiaNet (ELN) recommendation. In this study we aimed to validate the usefulness of 2017 ELN risk stratification in a large Taiwan cohort with special focus on the prognostic relevance of FLT3-ITD allelic ratio and its interaction with other mutations.MethodsWe retrospectively included 1040 de novo non-M3 AML patients. AML was risk-stratified according to the 2017 ELN recommendation. 739 (71.1%) patients who received standard chemotherapy were included for survival analysis. Allogeneic hematopoietic stem cell transplantation (HSCT) was performed in 293 (39.6%) patients. Mutational analyses of fifteen genes, including CEBPA, NPM1, FLT3, RUNX1, ASXL1, TP53, splicing factors (SF), such as SRSF2, U2AF1, and SF3B1, as well as KIT, NRAS, KRAS, DNMT3A, TET2, and WT1 were performed. FLT3-ITD/wild allelic ratios were calculated as the ratio of the area under the curve by fragment analysis. High FLT3-ITD allelic ratio (FLT3-ITDhigh) was defined as ³ 0.5 and low allelic ratio (FLT3-ITDlow) defined as < 0.5.ResultsAccording to the 2017 ELN risk classification, favorable, intermediate and adverse categories comprised 34.6%, 29.2% and 36.2% patients, respectively. NPM1 mutations and FLT3-ITD, the most common mutations in this cohort, were detected in 217 (20.9%) and 216 (20.8%) patients, respectively, with a significant association between each other. The median value of the FLT3-ITD/wild ratio was 0.68 without difference between NPM1-mutated and NPM1-wild group. Of note, patients with FLT3-ITDhigh had higher WBC count and LDH level than those with FLT3-ITDlow.Overall, the CR rate and relapse rate were 74.2% and 54.7%, respectively and 5-year overall survival (OS) was 43.2±1.9%. The CR rate (92.3%) was higher in the 2017 ELN favorable risk group than in the intermediate (73.0%) and adverse groups (52.0%, P<0.001). Similarly, favorable-risk patients had lower relapse rate, longer disease-free survival (DFS) and OS compared to those with intermediate- and adverse-risk features (all P<0.001).As to the prognostic impact of FLT3-ITD, we showed that FLT3-ITD patients had significantly lower CR rate, higher relapse rate, reduced DFS and OS than those without. There was a strikingly difference in treatment response between the low and high FLT3-ITD allelic ratio groups: CR rate (80.7% vs. 63.6%, P=0.0319), relapse rate (56.5% vs. 66.2%, P=0.329), DFS (14.2 vs. 4.6 months P=0.011) and OS (24.0 vs. 11.9 months, P=0.048). Interestingly, patients with FLT3-ITDhigh had a better OS if they received allogeneic HSCT than those who did not.Among the 2017 ELN favorable-risk category, we found that patients with mutated NPM1 and FLT3-ITDlow had significantly shorter OS (median, not reached vs. 31.6 months, P=0.003, Figure. 1A) and a trend of shorter DFS (median 14.9 months vs. 93.9 months, P=0.089, Figure. 1B) compared to other ELN favorable subgroups. To find the cause of the difference, we investigated the concurrent mutations in the patients with mutated NPM1 and FLT3-ITDlow. 46.2% of them had concurrent poor-risk mutations, such as ASXL1, RUNX1, TP53, WT1, TET2, DNMT3A, and SF mutations. Similarly, among the 2017 ELN intermediate-risk category, patients with mutated NPM1 and FLT3-ITDhigh had more unfavorable outcomes compared to those with wild-type NPM1 and without FLT3-ITD (DFS, median 3.7 vs. 11.6 months, P=0.028 and OS, median, 11.4 vs. 26.5 months, P=0.067). Presence of concurrent poor-risk mutations were also identified in 72.9% of these patients. Based on these findings, we postulated that concomitant poor-risk genetic alterations at least partially affected the prognosis of FLT3/ITD patients. In the cohort of FLT3-ITD patients, patients harboring poor-risk mutations had shorter DFS and OS than those without (P=0.028 and P=0.031, respectively). Further, co-occurrence of FLT3-ITDhigh and poor-risk mutations that predicted a worst outcome, seemed to define a highly adverse prognostic group.ConclusionsWe showed that ELN 2017 risk classification could well stratify AML patients in Taiwan. The prognostic relevance of FLT3-ITD may further depend on the presence or absence of co-occurring poor-risk genetic alterations, which seemed to add an adverse effect in patients with FLT3-ITD. These observations warrant confirmation in other prospective and large-scale studies. [Display omitted] DisclosuresKo:Roche: Research Funding; GNT Biotech & Medicals Crop.: Research Funding; Abbevie: Research Funding; Mumdipharma Taiwan: Consultancy.

When to obtain genomic data in acute myeloid leukemia (AML) and which mutations matter.

Mutational profiling has fundamentally changed our approach to patients with acute myeloid leukemia (AML). Patients with AML are routinely profiled for the presence of mutations in FLT3, NPM1, CEBPA, and, more recently, TP53 In this chapter, we review the role of mutational profiling to help define disease biology in AML, particularly among patients with putatively intermediate-risk disease. We describe the body of evidence supporting the utility of mutational profiling when performed at the time of diagnosis (to identify prognostic and targetable mutations), at the time of complete remission (to assess minimal residual disease as a marker for relapse), and at the time of relapse (to identify therapeutic targets and eligibility for clinical trials). We further identify particular mutations that have been shown to affect prognosis across the established European LeukemiaNet risk categories and discuss which mutational events might be used to alter the approach to patient care at various time points during the disease course. We also review the evidence in support of molecular profiling for assessment of minimal/measurable residual disease and describe the current landscape of studies designed to validate this approach.

Next-generation sequencing–based posttransplant monitoring of acute myeloid leukemia identifies patients at high risk of relapse

AbstractNext-generation sequencing (NGS) has been applied to define clinically relevant somatic mutations and classify subtypes in acute myeloid leukemia (AML). Persistent allelic burden after chemotherapy is associated with higher relapse incidence, but presence of allelic burden in AML patients after receiving allogeneic hematopoietic cell transplantation (HCT) has not been examined longitudinally. As such, we aimed to assess the feasibility of NGS in monitoring AML patients receiving HCT. Using a targeted gene panel, we performed NGS in 104 AML patients receiving HCT using samples collected at diagnosis, pre-HCT, and post-HCT at day 21 (post-HCTD21). NGS detected 256 mutations in 90 of 104 patients at diagnosis, which showed stepwise clearances after chemotherapy and HCT. In a subset of patients, mutations were still detectable pre-HCT and post-HCT. Most post-HCT mutations originate from mutations initially detected at diagnosis. Post-HCTD21 allelic burdens in relapsed patients were higher than in nonrelapsed patients. Post-HCTD21 mutations in relapsed patients all expanded at relapse. Assessment of variant allele frequency (VAF) revealed that overall VAF post-HCTD21 (VAF0.2%-post-HCTD21) is associated with an increased risk of relapse (56.2% vs 16.0% at 3 years; P < .001) and worse overall survival (OS; 36.5% vs 67.0% at 3 years; P = .006). Multivariate analyses confirmed that VAF0.2%-post-HCTD21 is an adverse prognostic factor for OS (hazard ratio [HR], 3.07; P = .003) and relapse incidence (HR, 4.75; P < .001), independent of the revised European LeukemiaNet risk groups. Overall, current study demonstrates that NGS-based posttransplant monitoring in AML patients is feasible and can distinguish high-risk patients for relapse.

1028P - Prognostic factors of clinical use in acute myeloid leukemia

Background: The heterogeneity in acute myeloid leukemia (AML) is influenced by disease and host-specific factors. In recent years, independent molecular factors and host characteristics that affect prognosis have been described. Nevertheless, data is needed to warrant their clinical use. Methods: We retrospectively reviewed data on 356 AML patients from October 2008 to June 2017, including age, Charlson Comorbity Index (CCI), ECOG performance status (PS), laboratory parameters (complete blood count, bone marrow blasts, lactic dehydrogenase) and disease factors (de novo or secondary AML (sAML), genetic alterations). The 2017 European Leukemia Net genetics risk stratification (GRS) was used. Univariate and multivariate Cox regression analysis was performed. Results: The intensive chemotherapy (IC) group comprised of 241 patients, median age 58 years (y), 95% having PS ≤ 1, 67% CCI ≤2 and 22% were sAML. GRS was 23% favorable, 44% intermediate, 27% adverse and 6% unknown. Median overall survival (OS) was 15 months (mo), with 28% 3y-OS. In multivariate analysis (Table), age older than 60y (median 6 versus (vs) 22mo), PS ≥ 2 (median 7 vs 15mo) and higher risk GRS (median 35mo favorable vs 13mo intermediate and 11mo adverse) impacted on survival. The non-IC group included 112 patients, median age 67y, 76% having PS ≤ 1, 6% CCI ≤2 and 37% were sAML. GRS was 12% favorable, 49% intermediate, 24% adverse and 15% unknown. Median OS was 3mo, with 10% 3y-OS. In multivariate analysis (Table), age older than 60y (median 2 vs 17mo), PS ≥ 2 (median 1 vs 5mo) and higher risk GRS (median not reached in favorable vs 4mo intermediate and 1mo adverse) impacted on prognosis.Table: 1028PIntensive chemotherapy HR [95% CI]Non-intensive therapy HR [95% CI]Age≤60 yearsRefRef>60 years2.41 [1.76-3.31]3.09 [1.70-5.65]ECOG PS≤ 1RefRef> 12.36 [1.23-4.53]2.25 [1.27-3.98]ELN2017 geneticsFavorableRefRefIntermediate2.04 [1.33-3.14]3.26 [1.30-8.15]Adverse2.26 [1.42-3.59]5.55 [2.13-14.44] Open table in a new tab Conclusions: In spite of the high number of recognized risk factors, in real-life only GRS, age and PS were of clinical use to predict survival in both IC and non-IC sets. In our sample, there was no significant impact of sAML, CCI and laboratory parameters. Efforts are needed to identify more factors that aid clinical decision in the treatment of AML. Legal entity responsible for the study: Clinical Hematology Department, Centro Hospitalar São João, EPE. Funding: Has not received any funding. Disclosure: All authors have declared no conflicts of interest.

NF1 mutations are recurrent in adult acute myeloid leukemia and confer poor outcome.

Targeted mutation assessment of 81 genes in 1,021 adults with de novo acute myeloid leukemia (AML) identified recurrent mutations in the neurofibromin 1 (NF1) gene in 52 (5.1%) patients, including 36 (5.2%) younger and 16 (4.8%) older patients, which suggests NF1 belongs to the 20 most frequently mutated genes in adult AML. NF1 mutations were found throughout the gene, and comprised missense, frame-shift and nonsense mutations. One mutation hotspot, at amino acid threonine 676 (Thr676), was found in 27% of AML patients with NF1 mutations. NF1-mutated patients belonged more often to the adverse European LeukemiaNet (ELN) risk category than NF1 wild-type patients. Among patients aged <60 years, the presence of NF1 Thr676 mutations was associated with lower complete remission (CR) rates (P=0.04) and shorter overall survival (OS; P=0.01), as was the presence of any NF1 mutation in patients in the adverse ELN risk category (CR, P=0.05; OS, P<0.001). CR rates were also lower in NF1-mutated patients aged ≥60 years compared with NF1 wild-type patients (P=0.001). In summary, our findings provide novel insights into the frequency of NF1 mutations in AML, and are suggestive of an adverse prognostic impact in patients treated with standard chemotherapy.

Validation of the Revised Pretransplant Assessment of Mortality Score in Patients with Acute Myelogenous Leukemia Undergoing Allogeneic Hematopoietic Stem Cell Transplantation

Despite recent advances, allogeneic hematopoietic stem cell transplantation (allo-HSCT) continues to be accompanied by a high rate of morbidity and mortality. Several scores have been developed to predict outcome after allo-HSCT. The recently revised Pretransplant Assessment of Mortality (PAM) score is based on patient age, donor type, disease risk, cytomegalovirus (CMV) serostatus of patient and donor, and forced expiratory volume in 1 second (FEV1). The aim of this study was to analyze the predictive power of the PAM score in an independent large cohort of patients with acute myelogenous leukemia (AML). We selected adult patients with AML who underwent a first allo-HSCT at the University Hospital of Dresden, a tertiary care hospital with a large transplantation program. All adult patients treated between January 1, 2003, and July 1, 2015, were included. The PAM score was calculated as described previously. Overall survival (OS), cumulative incidence of relapse (CIR), and nonrelapse mortality (NRM) after allo-HSCT were analyzed. Age, AML type, sex match, CMV match, donor type, European Leukemia Net risk classification, type of conditioning, disease stage, and PAM score as a continuous variable were selected a priori for multivariate Cox regression analyses. A total of 544 patients met the inclusion criteria. The median patient age was 57 years. With a median follow-up of 47 months (range, 1 to 161 months), the estimated OS for the whole cohort at 4 years was 43%, with a CIR of 30% and an NRM of 31%. The probability of OS at 4 years was 65% for patients with a PAM score of 0, 52% in those with a PAM score of 1, 33% in those with a PAM score of 2, and 22% in those with a PAM score of 3 (P < .001, log-rank test). Both the CIR and NRM increased with higher PAM scores (P = .005 and P < .001, respectively, Gray test). In multivariate analysis, age (hazard ratio [HR], 1.02 per year; P = .004), disease stage (primary induction failure versus first complete remission (CR1); HR, 1.5; P = .03), and the PAM score (HR 1.04; P = .03) had a significant impact on OS. This is the first independent validation of the revised PAM score allowing for simple and valid estimation of transplantation outcomes. It can serve as an important tool in counseling patients with AML, as well as in designing future trials.

Development and Validation of a Novel RNA Sequencing-Based Prognostic Score for Acute Myeloid Leukemia.

BackgroundRecent progress in sequencing technologies allows us to explore comprehensive genomic and transcriptomic information to improve the current European LeukemiaNet (ELN) system of acute myeloid leukemia (AML).MethodsWe compared the prognostic value of traditional demographic and cytogenetic risk factors, genomic data in the form of somatic aberrations of 25 AML-relevant genes, and whole-transcriptome expression profiling (RNA sequencing) in 267 intensively treated AML patients (Clinseq-AML). Multivariable penalized Cox models (overall survival [OS]) were developed for each data modality (clinical, genomic, transcriptomic), together with an associated prognostic risk score.ResultsOf the three data modalities, transcriptomic data provided the best prognostic value, with an integrated area under the curve (iAUC) of a time-dependent receiver operating characteristic (ROC) curve of 0.73. We developed a prognostic risk score (Clinseq-G) from transcriptomic data, which was validated in the independent The Cancer Genome Atlas AML cohort (RNA sequencing, n = 142, iAUC = 0.73, comparing the high-risk group with the low-risk group, hazard ratio [HR]OS = 2.42, 95% confidence interval [CI] = 1.51 to 3.88). Comparison between Clinseq-G and ELN score iAUC estimates indicated strong evidence in favor of the Clinseq-G model (Bayes factor = 26.78). The proposed model remained statistically significant in multivariable analysis including the ELN and other well-known risk factors (HRos = 2.34, 95% CI = 1.30 to 4.22). We further validated the Clinseq-G model in a second independent data set (n = 458, iAUC = 0.66, adjusted HROS = 2.02, 95% CI = 1.33 to 3.08; adjusted HREFS = 2.10, 95% CI = 1.42 to 3.12).ConclusionsOur results indicate that the Clinseq-G prediction model, based on transcriptomic data from RNA sequencing, outperforms traditional clinical parameters and previously reported models based on genomic biomarkers.

Early Post-Transplant Minimal Residual Disease Assessment Improves Risk Stratification in Acute Myeloid Leukemia

We studied if the inclusion of early post–stem cell transplantation (SCT) minimal residual disease (MRD) assessments improved prognostication in patients with acute myeloid leukemia (AML). Two hundred sixty-nine AML patients in morphological complete remission (CR) who underwent a first SCT were included if they had evaluable pre-SCT MRD assessment by multiparametric flow cytometry. Post-SCT MRD assessments were performed at days +30, +100, and +180. The primary outcome was 1-year relapse incidence (RI). Of 269 patients in CR, 83 (30.8%) had detectable MRD pre-SCT. Post-SCT, during routine disease assessment time points, 9 of 241 evaluable patients (3.7%) at day +30, 6 of 191 evaluable patients (3.1%) at day +100, and 4 of 133 evaluable patients (3%) at day +180 were MRD positive while in CR. MRD positivity at day +30 predicted the highest risk of relapse at 1 year (group 1, 1-year RI 78%). Among MRD-negative patients at day +30, either adverse risk category by European Leukemia Net (ELN) or intermediate risk who were aged ≥60 years and/or pre-SCT MRD-positive represented the intermediate-risk group (group 2, 1-year RI 29%). The remaining patients represented the low-risk group (group 3, 1-year RI 5%). For patients in CR beyond day +30 post-SCT, detectable MRD at any time point predicted impending relapse within 2 months. Early post-SCT MRD assessment—combined with pre-SCT MRD assessment, ELN risk category, and age—improves risk stratification for relapse in AML patients post-transplant. Studies aimed at preventing impending relapse in this high-risk population are urgently needed.

Incorporation of Long Non-Coding RNA Expression Profile in the 2017 ELN Risk Classification Can Improve Prognostic Prediction of Acute Myeloid Leukemia Patients

Background: Expression of long non-coding RNAs (lncRNAs) has recently been recognized as a potential prognostic marker in acute myeloid leukemia (AML). However, it remains unclear whether incorporation of the lncRNAs expression in the 2017 European LeukemiaNet (ELN) risk classification can further improve the prognostic prediction. Methods: We enrolled 275 newly diagnosed non-M3 AML patients and randomly assigned them into the training (n=183) and validation cohorts (n=92). In the training cohort, we formulated a prognostic lncRNA scoring system composed of five lncRNAs with significant prognostic impact from the lncRNA expression profiling. Findings: Higher lncRNA scores were significantly associated with older age and adverse gene mutations. Further, the higher-score patients had shorter overall and disease-free survival than lower-score patients, which were also confirmed in both internal and external validation cohorts (TCGA database). The multivariate analyses revealed the lncRNA score was an independent prognosticator in AML, irrespective of the risk based on the 2017 ELN classification. Moreover, in the 2017 ELN intermediate-risk subgroup, lncRNA scoring system could well dichotomize the patients into two groups with distinct prognosis. Within the ELN intermediate-risk subgroup, we found that allogeneic hematopoietic stem cell transplantation could provide better outcome on patients with higher lncRNA scores. Through bioinformatics approach, we identified high lncRNA scores were correlated with leukemia/hematopoietic stem cell signatures. Interpretation: Incorporation of lncRNA scoring system in 2017 ELN classification can improve risk-stratification of AML patients and help clinical decision-making. Funding Statement: This work was supported Ministry of Science and Technology, and Ministry of Health and Welfare of Taiwan. Declaration of Interests: The authors declare no competing interests. Ethics Approval Statement: This study was approved by the Research Ethics Committee of the NTUH in accordance with the Declaration of Helsinki.

Prognostic analysis according to the 2017 ELN risk stratification by genetics in adult acute myeloid leukemia patients treated in the Japan Adult Leukemia Study Group (JALSG) AML201 study

Many genetic alterations that are associated with the prognosis of acute myeloid leukemia (AML) have been identified, and several risk stratification systems based on the genetic status have been recommended. The European LeukemiaNet (ELN) first proposed the risk stratification system for AML in 2010 (ELN-2010), and recently published the revised system (ELN-2017). We validated the long-term prognosis and clinical characteristics of each ELN-2017 risk category in Japanese adult AML patients who were treated in the Japan Adult Leukemia Study Group (JALSG) AML-201 study. We demonstrated that the 3-risk category system of the ELN-2017 successfully discriminated the overall survival and complete remission rates in our cohort in comparison with the 4-risk category of the ELN-2010. However, there were still genetic categories in which stratification of patients into favorable or intermediate risk categories was controversial; the low allelic ratio of FLT3-ITD was not necessarily associated with a better prognosis in patients with FLT3-ITD, and cytogenetic abnormalities may affect the prognosis in patients with favorable genetic lesions such as NPM1 and CEBPA mutations. As many molecular targeting agents, such as FLT3 inhibitors, have been developed, we must continue to modify the genetic risk stratification system to match the progression of therapeutic strategies.

Epidemiological, genetic, and clinical characterization by age of newly diagnosed acute myeloid leukemia based on an academic population-based registry study (AMLSG BiO)

We describe genetic and clinical characteristics of acute myeloid leukemia (AML) patients according to age from an academic population-based registry. Adult patients with newly diagnosed AML at 63 centers in Germany and Austria were followed within the AMLSG BiO registry (NCT01252485). Between January 1, 2012, and December 31, 2014, data of 3525 patients with AML (45% women) were collected. The median age was 65 years (range 18–94). The comparison of age-specific AML incidence rates with epidemiological cancer registries revealed excellent coverage in patients < 70 years old and good coverage up to the age of 80. The distribution according to the European LeukemiaNet (ELN) risk categorization from 2010 was 20% favorable, 31% intermediate-1, 28% intermediate-2, and 21% adverse. With increasing age, the relative but not the absolute prevalence of patients with ELN favorable and intermediate-1 risk (p < 0.001), with activating FLT3 mutations (p < 0.001), with ECOG performance status < 2 (p < 0.001), and with HCT-CI comorbidity index < 3 (p < 0.001) decreased. Regarding treatment, obesity and favorable risk were associated with an intensive treatment, whereas adverse risk, higher age, and comorbidity index > 0 were associated with non-intensive treatment or best supportive care. The AMLSG BiO registry provides reliable population-based distributions of genetic, clinical, and treatment characteristics according to age.

Validation of risk stratification models in acute myeloid leukemia using sequencing-based molecular profiling.

Risk stratification of acute myeloid leukemia (AML) patients needs improvement. Several AML risk classification models based on somatic mutations or gene-expression profiling have been proposed. However, systematic and independent validation of these models is required for future clinical implementation. We performed whole-transcriptome RNA-sequencing and panel-based deep DNA sequencing of 23 genes in 274 intensively treated AML patients (Clinseq-AML). We also utilized the The Cancer Genome Atlas (TCGA)-AML study (N=142) as a second validation cohort. We evaluated six previously proposed molecular-based models for AML risk stratification and two revised risk classification systems combining molecular- and clinical data. Risk groups stratified by five out of six models showed different overall survival in cytogenetic normal-AML patients in the Clinseq-AML cohort (P-value<0.05; concordance index >0.5). Risk classification systems integrating mutational or gene-expression data were found to add prognostic value to the current European Leukemia Net (ELN) risk classification. The prognostic value varied between models and across cohorts, highlighting the importance of independent validation to establish evidence of efficacy and general applicability. All but one model replicated in the Clinseq-AML cohort, indicating the potential for molecular-based AML risk models. Risk classification based on a combination of molecular and clinical data holds promise for improved AML patient stratification in the future.

Simple matters in complex times.

Simple matters in complex times.

Outcome of Acute Myeloid Leukemia (AML) Induction Therapy Based on D14 Marrow Biopsy According to European Leukemia Net (ELN) Risk Classification

OBJECTIVEAccording to standard protocol, the earliest post treatment marker of response following intensive induction therapy in patients with AML is a D14 marrow biopsy. Some controversy has surrounded this practice. This study aims to evaluate response to induction therapy based on D14 marrow assessment meeting genetic risk classifications as defined by the ELN. METHODSIn a single center, retrospective chart analysis subjects diagnosed with AML treated with 7+3 therapy were included if they had molecular and cytogenetic testing performed at baseline, day 14, and day 28. Baseline characteristics and treatment results at these time points were extracted. Sample demographics and treatment were described descriptively. Risk ratios were calculated to investigate the likelihood of achieving a chemo-ablated[1] bone marrow biopsy at Day 14 across the ELN risk classifications. All analyses were performed using SAS 9.4 (SAS Institute Inc., Cary, NC). RESULTSOne hundred thirty eight pts were included. The median age at diagnosis was 57 years (range 26 to 69). The median white blood cell count at diagnosis was 12,800 (range 0.1 to 122,000 per microliter). 6.5% of the pts had secondary AML and 8.7% had AML arising from an antecedent hematologic disorder. ELN risk classifications at diagnosis were 47.1%, 8.7%, 20.3% and 23.9% for favorable, intermediate-I, intermediate-II and adverse, respectively. Demographic variables and baseline characteristics did not differ across risk groups. The percentage of pts achieving a chemo-ablated marrow biopsy at Day 14 was 88%, 83%, 68% and 67% for the Favorable, Intermediate-I, Intermediate-II and Adverse group, respectively (Table 1, p=0.0385). Similarly, the percentage of patients achieving CR at Day 28 was highest for patients with a favorable ELN risk classification (92%) compared to intermediate-I (83%), intermediate-II (71%) and adverse (79%) (Table 2, p=0.0440). Re-induction rate was significantly different when stratified across ELN risk groups (p=0.0487). Risk ratio analysis showed a 26% increased likelihood of achieving a chemo-ablated marrow biopsy when comparing Favorable ELN risk pts to those to those in the non-favorable ELN risk group (RR:1.2552; 95% CI: 1.0526-1.468). A test of discordance comparing hypocellular/hypercellular results based on the Day 14 marrow biopsy with having CR/non CR at end of cycle 1 were not significant across the ELN risk classifications. CONCLUSIONWith the advent of personalized therapy comes the potential to customize treatment and hope to optimize pt outcomes. Our results indicate that karyotype and a range of genetic mutations predict marrow morphology at Day 14. How these results predict long-term outcome needs to be further explored.[1] (defined as cellularity <10% and residual blasts <5%) DisclosuresRay:Ipsen Biopharmaceuticals: Employment. Koprivnikar:Alexion: Consultancy, Speakers Bureau. McCloskey:Amgen: Speakers Bureau; Ariad: Consultancy, Speakers Bureau; Novartis: Speakers Bureau; Incyte: Consultancy. Stanislaus:Novartis: Consultancy, Speakers Bureau. Howlett:Pfizer: Honoraria; Sandoz: Honoraria; Teva: Speakers Bureau; Amgen: Honoraria; Eisai: Honoraria. Depadova:Amgen: Speakers Bureau. Goldberg:Novartis: Consultancy; Pfizer: Honoraria; Bristol Myers Squibb, Novartis: Speakers Bureau; Neostem: Equity Ownership; COTA Inc: Employment.

Transplant outcomes of the triple-negative NPM1/FLT3-ITD/CEBPA mutation subgroup are equivalent to those of the favourable ELN risk group, but significantly better than the intermediate-I risk group after allogeneic transplant in normal-karyotype AML.

The prognostic significance of molecular mutations (FLT3-ITD, NPM1, and CEBPA mutations) was examined in patients with normal-karyotype acute myeloid leukaemia (NK-AML) after allogeneic haematopoietic cell transplantation (HCT). In total, 115 patients received allogeneic HCT for NK-AML and were evaluated for FLT3-ITD, NPM1, and CEBPA mutations in diagnostic samples and for long-term outcomes following HCT, retrospectively. The prevalences of FLT3-ITD(pos), NPM1 (mut), and CEBPA (dm) (double mutations) were 32.2, 43.5, and 24.6%, respectively. The triple-negative group (NPM1 (wild)/FLT3-ITD(neg)/non-CEBPA (dm)) showed a similar transplant outcome to those in the favourable European LeukemiaNet (ELN) risk group for overall survival (OS) (60.9 vs. 63.7%; p = 0.810), but a more favourable OS than others in the intermediate-I risk group (40.0%; p = 0.034). Also, the triple-negative group showed a similar relapse rate at 5years compared with those in the favourable risk group (9.7 vs. 15.5%; p = 0.499), but a lower rate of relapse than the others in the intermediate-I risk group (15.5 vs. 48.6%; p = 0.004). The 5-year relapse incidences were 4.0% (NPM1 (mut)/FLT3-ITD(neg)), 14.7% (CEBPA (dm)), 15.5% (NPM1 (wild)/FLT3-ITD(neg)/non-CEBPA (dm)), 39.1% (NPM1 (mut)/FLT3-ITD(pos)/non-CEBPA (dm)), and 66.7% (NPM1 (wild)/FLT3-ITD(pos)/non-CEBPA (dm)). Thus, the triple-negative (NPM1 (wild)/FLT3-ITD(neg)/non-CEBPA (dm)) group showed favourable long-term outcomes after allogeneic HCT in NK-AML, similar to those of the favourable risk group by the ELN risk classification.

Dose-Escalation Study of Azacitidine Followed By High-Dose Cytarabine (HiDAC) and Mitoxantrone (Mito) for Remission Induction in High-Risk Acute Myeloid Leukemia (AML)

Dose-Escalation Study of Azacitidine Followed By High-Dose Cytarabine (HiDAC) and Mitoxantrone (Mito) for Remission Induction in High-Risk Acute Myeloid Leukemia (AML)

Unsupervised Cluster Analysis of Antigen Expression Patterns Identifies Subgroups with Distinct Biological and Clinical Features in Patients with Acute Myeloid Leukemia Undergoing Allogeneic Stem Cell Transplantation

Characterisation of antigen expression patterns is part of the standard diagnostic work-up in acute myeloid leukemia (AML). But the biological & clinical implication of such antigen expression patterns have not been studied extensively & remain unclear in AML patients (pts) undergoing allogeneic stem cell transplantation (SCT).We analyzed the diagnostic antigen expression patterns of 162 AML pts (median age 64.7 years [y, range 46.6-76.2y]) with available data who received allogeneic peripheral blood SCT after non-myeloablative conditioning (NMA-SCT) between 2001 & 2013 at our institution. Conditioning regimen was fludarabine 3x30mg/m2 & 2Gy total body irradiation. Donors were human leukocyte antigen (HLA) matched related (12%) or HLA matched (59%) or mismatched unrelated (29%). Mutation (mut) status of the NPM1, CEBPA, IDH1, IDH2 &DNMT3A gene, presence of FLT3 -ITD &FLT3-TKD & the expression status of BAALC, ERG, MN1, EVI1, miR-9 &miR-181a at diagnosis were accessed. Pts were grouped according to the European LeukemiaNet (ELN) genetic classification in 22% favorable (fav), 24% intermediate-I (int-I), 21% intermediate-II (int-II) & 32% adverse (adv). Median follow up was 3.2y. To assess antigen expression patterns at diagnosis for all pts, flow cytometric analysis utilizing a standard panel (CD2, CD7, CD11b, CD13, CD14, CD15, CD33, CD34, CD38, CD45, CD56, CD61, CD64, CD65, CD117 & Glycophorin A) of mononuclear cells in bone marrow (BM) was performed. Using R's gplot package we performed unsupervised hierarchical clustering of the antigen expression which revealed 4 subgroups with distinct antigen expression patterns (Figure 1).At diagnosis, pts grouped in cluster 1 (n=19) had higher white blood count (WBC, P =.004) & lower peripheral blood (PB) blast count (P =.03) & were more likely to have de novo AML (P =.05). They were also less likely to have trisomy 8 (P =.08) by trend & more likely to have normal karyotype (KT, P =.05), to have ELN fav risk (P =.04), to be NPM1 mut (P =.002) & to be DNMT3A mut by trend (P =.08) & had lower miR-181a (P =.04), lower BAALC (P<.001), lower ERG (P =.01) & lower MN1 expression (P<.001).Pts grouped in cluster 2 (n=35) had higher WBC (P<.001), PB blasts (P<.001) & BM blasts (P =.005) at diagnosis. They were less likely to have trisomy 8 (P =.008) & to have deletion (del) 7/7q (P =.07) by trend, were more likely to be NPM1 mut (P =.002) & to have FLT3 -ITD (P <.001) & had lower BAALC (P =.1) & lower EVI1 expression (P =.09) by trend.Pts grouped in cluster 3 (n=59) had lower WBC (P<.001), PB blasts (P<.001) & BM blasts (P<.001) at diagnosis & were less likely to have de novo AML (P<.001). They were more likely to have trisomy 8 (P =.05), del5/5q (P =.004), monosomal KT (P =.04), complex KT (P =.07) by trend & ELN adv risk (P =.04), were less likely to be NPM1 mut (P =.03) &FLT3 -ITD by trend (P =.08) & had lower ERG (P =.008) & higher miR-9 (P =.009) expression.Pts grouped in cluster 4 (n=49) had lower WBC (P =.03), higher PB blasts (P =.007) & BM blasts (P<.001) at diagnosis. They were less likely to have del5/5q (P =.008) &NPM1 mut (P <.001) & had lower miR-9 (P =.007) & higher BAALC (P<.001), ERG (P<.001) &MN1 (P<.001) expression.For the entire set of pts, belonging to one of the antigen expression clusters did not impact on outcome. However, when the ELN groups were regarded separately, within the ELN fav group, cluster 1 pts had a significantly shorter event free survival (EFS, P =.04, Figure 2A) & within the ELN int-I group, cluster 3 pts had a trend for better (P =.096) & cluster 4 pts for worse EFS (P =.087).In conclusion, the antigen expression patterns at diagnosis obtained by unsupervised cluster analysis associated with distinct biological & clinical features (Figure 2B): NPM1 mut were enriched in clusters 1 & 2. Cluster 1 was characterized by ELN fav risk, normal KT, de novo disease & lower BAALC, ERG, MN1 &miR-181a expression. Cluster 2 was characterized by a high incidence of FLT3-ITD. We found more pts with ELN adv risk, monosomal KT, secondary AML & low miR-9 expression in cluster 3 & higher miR-9 as well as lower BAALC, ERG &MN1 expression levels in cluster 4. Even though we did not observe a prognostic impact of the antigen expression patterns in the entire cohort, the patterns may help to refine the ELN risk classification for AML pts undergoing SCT. Assessing the diagnostic antigen expression patterns provides information on disease biology, clinical parameters and potentially disease aggressiveness in AML. [Display omitted] [Display omitted] DisclosuresFranke:BMS: Honoraria; MSD: Other: Travel Costs; Novartis: Other: Travel Costs. Niederwieser:Novartis: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau.

Pretreatment d-2-hydroxyglutarate serum levels negatively impact on outcome in IDH1-mutated acute myeloid leukemia

Mutations in isocitrate dehydrogenases (IDHs) 1 and 2 frequently occur in acute myeloid leukemia (AML) and result in the production of the oncometabolite d-2-hydroxyglutarate (D2HG). D2HG has been shown to promote leukemogenesis even in the absence of mutated IDH, but the prognostic significance of pretreatment serum D2HG levels in patients with IDH-mutated AML is unclear. We measured D2HG serum levels in 84 patients with IDH-mutated AML treated in the prospective, randomized multicenter AML2003 trial of the German Study Alliance Leukemia. Multivariate Cox regression showed D2HG levels to negatively impact on event-free survival (EFS) as a continuous variable in the entire IDH(mut) cohort (P=0.04), with no effect on overall survival (OS). In a subgroup analysis, the negative impact of D2HG on EFS was found to be restricted to patients with mutations in IDH1 (P=0.003), adjusted for age, leukocyte count, serum lactate dehydrogenase and European LeukemiaNet risk score. We thus conclude that pretreatment D2HG serum levels may yield prognostic information in patients with IDH1-mutated, but not in IDH2-mutated AML, possibly due to different subcellular localizations of IDH1 and IDH2.

Age and Modified European LeukemiaNet Classification to Predict Transplant Outcomes: An Integrated Approach for Acute Myelogenous Leukemia Patients Undergoing Allogeneic Stem Cell Transplantation

We evaluated the prognostic significance of a modified European LeukemiaNet (ELN) classification for patients with acute myelogenous leukemia (AML) undergoing hematopoietic stem cell transplantation (HSCT) while in first complete remission (CR1). We analyzed 464 AML patients with matched related (n = 211, 45.5%), matched unrelated (n = 176, 37.9%), and mismatched donors (n = 77, 16.6%). Patients were classified into 4 modified ELN risk groups (favorable, intermediate-I, intermediate-II, and adverse) separately for 354 patients age < 60 years and 110 patients age ≥ 60 years. In this modified version of ELN classification, patients with normal cytogenetic were classified by FLT3-ITD mutational status: favorable risk if FLT3-ITDwild and intermediate-I if FLT3-ITDmut. The best outcomes occurred in the ELN favorable and intermediate-II groups in younger AML patients and in the favorable and intermediate-I groups in older AML patients. Older AML patients had worse transplant outcomes within each modified ELN risk group except intermediate-I when compared with younger patients; leukemia-free survival at 3 years was 67.8% versus 49.8% in favorable, 53.4% versus 50.7% in intermediate-I, 65.7% versus 20.2% in intermediate-II, and 44.6% versus 23.8% in adverse group younger and older patients, respectively. Among lesion-specific abnormalities, del5q/−5 and abnl(17p) had the worse transplant outcomes, with 3-year leukemia-free survival rates of 18.4% and 20% in younger CR1 patients. In conclusion, the modified ELN prognostic classification developed for chemotherapy outcomes also identifies prognostic groups for HSCT, which is useful for a selection of patients for post-transplant strategies to improve outcomes.

Validating the Patient’s “Fitness” Criteria Proposed to Guide Treatment Decision in Elderly AML: a Multicenter Study on a Population-Based Series of 362 Patients By the Network “Rete Ematologica Lombarda” (REL)

BACKGROUNDMedian age of patients (pts) with acute myeloid leukemia (AML) ranges between 69 and 72 years in population-based series (SEER, 2012; Juliusson, 2009). The prognosis of elderly AML is exceedingly poor with overall 2-year survival of 10% (Juliusson, 2011). The use of intensive chemotherapy (i-CT) in elderly AML patients as opposed to non-intensive chemotherapy (ni-CT) or best supportive care (BSC) is still debated. Age is still the major driver of treatment choice but, in recent years, the role of pts’ fitness and comorbidities was underscored. In 2013, a panel of experts proposed a set of objective criteria to define pts fit or unfit to conventional i-CT, ni-CT or BSC (Ferrara et al, Leukemia, 2013). Since such criteria derived from experts opinion, they need to be validated in the clinical setting to become an useful tool for therapy decision making. AIMSFitness criteria were retrospectively applied to a population-based series of pts with AML (no M3), to evaluate a) their actual applicability; b) the concordance between “fitness” categorization of pts and the type of treatment they actually received; c) the outcome of pts according to “fitness”, to the prognostic stratification of European Leukemianet (ELN) and to the treatment received.PATIENTS and METHODS. We evaluated 362 pts aged > 65 y, diagnosed at five Hematology Centres of the Hematological Network of Lombardy in Northern Italy (REL). Pts were diagnosed between January 2008 and May 2014. Their median age was 73 y (range 65-94 y). Their categorization according to “fitness” criteria was carried out retrospectively by the teams of physicians who had followed pts and through medical files. Pts were classified as fit to i-CT (FIT), unfit to i-CT (UNFIT), or unfit even to ni-CT (FRAIL). According to ELN prognostic criteria, applied in 201 “de novo” AML, pts were at low-risk (36 pts: 18%), of which 7 (3,4%) with CBF leukemia, intermediate-I (75 pts: 37%), intermediate-II (30 pts: 15%), or high risk (60 pts: 30%). Criteria were not applicable in 34 pts (14%) lacking karyotype or molecular data. The group of 127 pts (35%) with AML therapy-related or secondary to myeloid neoplasms was considered at high clinical risk (cHR). According to physicians decision, 139 pts (38.4%) had received i-CT, 65 pts (18%) ni-CT, including low-dose arac, azacytidine or experimental non-myelotoxic drugs, and 158 pts (43.6%) BSC.RESULTS. Fitness criteria were not applicable in 12 pts (3%), because of insufficient data. Among 350 evaluable pts (97%), 170 (46.9%) were FIT, 140 (38.7%) were UNFIT, and 40 (11%) were FRAIL. Their median age was 69, 79 and 75 years, respectively (p <0.0001). Median overall survival (OS) of FIT, UNFIT and FRAIL pts was 12.5, 3.7 and 1.8 months, respectively (FIT vs others: P=0.0001, UNFIT vs FRAIL: p=0.049) (Figure 1). Overall concordance between “fitness criteria” and the treatment actually received by pts was 80% (71% in FIT, 88% in UNFIT and 90% in FRAIL pts). Median OS of pts receiving i-CT, ni-CT or BSC was 14.7, 14.2 and 4.2 months in FIT, (p<0.0001), 8.6, 8.9, 2 months in UNFIT (p<0.0001) (i-CT vs ni-CT: P:NS), respectively. Median OS inFRAIL pts receiving ni-CT (4 pts only) or BSC was 11.5 and 2 months, respectively (p:NS). Considering pts receiving i-CT, their outcome was significantly related both to ELN/clinical risk and to fitness. CR rate was 96.5% in LR, 66% in Int-I, 54% in Int-II, 46% in HR, 53% in cHR (p=0.0013). OS at 2y was 40% in LR/Int-I vs 25% in Int-II/HR/cHR pts (P=0.04). Median OS was 14.7 in FIT vs 8.6 months in UNFIT/FRAIL pts (P=0.022). By integrating ELN prognostic stratification with fitness, the use of i-CT obtained a significantly better median OS of 20 months in FIT pts at ELN LR/Int-I compared to 8,5 months in pts at Int-II/HR/cHR (p 0.014) (Figure 2).CONCLUSIONS. The “fitness criteria” proposed were easily applicable even retrospectively and in a multicenter setting. Fitness was significantly related to patient’s survival. In FIT and UNFIT pts outcome was similar with either i-CT or ni-CT, but these results need to be tested prospectively on larger cohorts. Integrating fitness with ELN criteria identifies a subgroup of FIT pts at low/Int-I ELN risk with a CR rate of 76.6% and a median OS of 20 months when treated with i-CT. Therefore fitness criteria seem to be a good tool to identify pts who can benefit from i-CT or ni-CT in alternative to BSC and to assist in the decision to use i-CT in elderly AML patients. [Display omitted] [Display omitted] DisclosuresNo relevant conflicts of interest to declare.