Age-related risk profile and chemotherapy dose response in acute myeloid leukemia: a study by the German Acute Myeloid Leukemia Cooperative Group

Acute Myeloid Leukemia: Aging and Epigenetics

Acute myeloid leukemia (AML) is an aggressive hematological disorder mainly affecting people of older age. AML initiation is primarily attributed to mutations in crucial cellular regulators such as epigenetic factors, transcription factors, and signaling genes. AML’s aggressiveness and responsiveness to treatment depends on the specific cell type where leukemia first arose. Aged hematopoietic cells are often genetically and/or epigenetically altered and, therefore, present with a completely different cellular context for AML development compared to young cells. In this review, we summarize key aspects of AML development, and we focus, in particular, on the contribution of cellular aging to leukemogenesis and on current treatment options for elderly AML patients. Hematological disorders and leukemia grow exponentially with age. So far, with conventional induction therapy, many elderly patients experience a very poor overall survival rate requiring substantial social and medical costs during the relatively few remaining months of life. The global population’s age is increasing rapidly without an acceptable equal growth in therapeutic management of AML in the elderly; this is in sharp contrast to the increase in successful therapies for leukemia in younger patients. Therefore, a focus on the understanding of the biology of aging in the hematopoietic system, the development of appropriate research models, and new therapeutic approaches are urged.

Gemtuzumab Ozogamicin in NPM1-Mutated Acute Myeloid Leukemia: Early Results From the Prospective Randomized AMLSG 09-09 Phase III Study

PURPOSE

High CD33 expression in acute myeloid leukemia (AML) with mutated NPM1 provides a rationale for the evaluation of gemtuzumab ozogamicin (GO) in this AML entity. We conducted a randomized trial to evaluate GO in combination with intensive induction and consolidation therapy in NPM1-mutated AML.

PATIENTS AND METHODS

Between May 2010 and September 2017, patients ≥ 18 years old and considered eligible for intensive therapy were randomly assigned up front for induction therapy with idarubicin, cytarabine, etoposide, and all-trans-retinoic acid with or without GO. The early (P = .02) primary end point of event-free survival (EFS) was evaluated 6 months after completion of patient recruitment.

RESULTS

Five hundred eighty-eight patients were randomly assigned (standard arm, n = 296; GO arm, n = 292). EFS in the GO arm was not significantly different compared with that in the standard arm (hazard ratio, 0.83; 95% CI, 0.65 to 1.04; P = .10). The early death rate during induction therapy was 10.3% in the GO arm and 5.7% in the standard arm (P = .05). Causes of death in both arms were mainly infections. The cumulative incidence of relapse (CIR) in patients achieving a complete remission (CR) or CR with incomplete hematologic recovery (CRi) was significantly reduced in the GO arm compared with the standard arm (P = .005), with no difference in the cumulative incidence of death (P = .80). Subgroup analysis revealed a significant beneficial effect of GO in female, younger (≤ 70 years), and FLT3 internal tandem duplication-negative patients with respect to EFS and CIR.

CONCLUSION

The trial did not meet its early primary end point of EFS, mainly as a result of a higher early death rate in the GO arm. However, in patients achieving CR/CRi after induction therapy, significantly fewer relapses occurred in the GO compared with the standard arm.

Characterization of a 4 lncRNAs-based prognostic risk scoring system in adults with acute myeloid leukemia

PURPOSE

The study aims to develop a prognostic scoring system based on prognostic lncRNAs for acute myeloid leukemia (AML).

METHODS

Based on lncRNA expression profiles downloaded from The Cancer Genome Atlas (TCGA), differentially expressed long noncoding RNAs (DELs) between good prognosis and bad prognosis samples were screened, from which prognosis-related lncRNAs were selected using uni-variate and multi-variate Cox regression analysis. Based on the expression profiles of these signature prognosis-related lncRNAs, a risk scoring system was developed and applied to a training set and validated on a testing set. With sample-matched mRNAs of the signature lncRNAs, lncRNA-mRNA networks were built, followed by function analysis for the mRNAs in these networks.

RESULT

Total 66 DELs were identified between good prognosis and bad prognosis samples. Among these DELs, LINC01003, CTD-2234N14, RP1-137K24, and RP11-834C111 were found to be independent predictors of prognosis. A risk scoring system based on the expressions of the 4 signature lncRNAs was developed. Kaplan-Meier survival analysis found that the risk score system could classify patients into high-risk and low-risk groups with significantly different survival outcomes. Function analysis showed that the mRNAs in these lncRNA-mRNA networks were significantly linked to mTOR signaling pathway, apoptosis, Fc epsilon RI signaling pathway, B cell receptor signaling pathway, natural killer cell mediated cytotoxicity, and T cell receptor signaling pathway.

CONCLUSION

This study suggested a promising 4 prognostic lncRNAs-based risk scoring system in AML. These 4 lncRNAs may play roles in regulating prognosis partly via mTOR signaling pathway, apoptosis, and some immune-related pathways.

Will new agents impact survival in AML?

In recent years, several drugs-including midostaurin, gilteritinib, and gemtuzumab ozogamicin, to name a few-have been approved or reapproved in the United States to treat patients with acute myeloid leukemia (AML). Yet survival rates for younger patients had improved with chemotherapy alone even before the approvals of these new agents. This begs the question whether the new therapies will actually have a positive impact on survival. The 5-year survival rate for older patients has also risen, again without the addition of these new agents. The challenge will be to incorporate new therapies and use them where they will have the greatest impact-major work for clinicians and researchers alike.

HLA-Mismatched Microtransplant in Older Patients Newly Diagnosed With Acute Myeloid Leukemia: Results From the Microtransplantation Interest Group

Importance

The outcome of older patients with acute myeloid leukemia (AML) remains unsatisfactory. Recent studies have shown that HLA-mismatched microtransplant could improve outcomes in such patients.

Objective

To evaluate outcomes in different age groups among older patients with newly diagnosed AML who receive HLA-mismatched microtransplant.

Design, Setting, and Participants

This multicenter clinical study included 185 patients with de novo AML at 12 centers in China, the United States, and Spain in the Microtransplantation Interest Group. Patients were divided into the following 4 age groups: 60 to 64 years, 65 to 69 years, 70 to 74 years, and 75 to 85 years. The study period was May 1, 2006, to July 31, 2015.

Exposures

Induction chemotherapy and postremission therapy with cytarabine hydrochloride with or without anthracycline, followed by highly HLA-mismatched related or fully mismatched unrelated donor cell infusion. No graft-vs-host disease prophylaxis was used.

Main Outcomes and Measures

The primary end point of the study was to evaluate the complete remission rates, leukemia-free survival, and overall survival in different age groups. Additional end points of the study included hematopoietic recovery, graft-vs-host disease, relapse rate, nonrelapse mortality, and other treatment-related toxicities.

Results

Among 185 patients, the median age was 67 years (range, 60-85 years), and 75 (40.5%) were female. The denominators in adjusted percentages in overall survival, leukemia-free survival, relapse, and nonrelapse mortality are not the sample proportions of observations. The overall complete remission rate was not significantly different among the 4 age groups (75.4% [52 of 69], 70.2% [33 of 47], 79.1% [34 of 43], and 73.1% [19 of 26). The 1-year overall survival rates were 87.7%, 85.8%, and 77.8% in the first 3 age groups, which were much higher than the rate in the fourth age group (51.7%) (P = .004, P = .008, and P = .04, respectively). The 2-year overall survival rates were 63.7% and 66.8% in the first 2 age groups, which were higher than the rates in the last 2 age groups (34.2% and 14.8%) (P = .02, P = .03, P < .001, and P < .001, respectively). The 1-year cumulative incidences of nonrelapse mortality were 10.2%, 0%, 3.4%, and 26.0% in the 4 age groups and 8.1% in all patients. The median times to neutrophil and platelet recovery were 12 days and 14 days after induction chemotherapy, respectively. Five patients had full or mixed donor engraftment, and 30.8% (8 of 26) of patients demonstrated donor microchimerism. Two patients (1.1%) developed severe acute graft-vs-host disease.

Conclusions and Relevance

Microtransplant achieved a high complete remission rate in AML patients aged 60 to 85 years and higher 1-year overall survival in those aged 60 to 74 years.

Metabolic Plasticity of Acute Myeloid Leukemia

Acute myeloid leukemia (AML) is one of the most common and life-threatening leukemias. A highly diverse and flexible metabolism contributes to the aggressiveness of the disease that is still difficult to treat. By using different sources of nutrients for energy and biomass supply, AML cells gain metabolic plasticity and rapidly outcompete normal hematopoietic cells. This review aims to decipher the diverse metabolic strategies and the underlying oncogenic and environmental changes that sustain continuous growth, mediate redox homeostasis and induce drug resistance in AML. We revisit Warburg's hypothesis and illustrate the role of glucose as a provider of cellular building blocks rather than as a supplier of the tricarboxylic acid (TCA) cycle for energy production. We discuss how the diversity of fuels for the TCA cycle, including glutamine and fatty acids, contributes to the metabolic plasticity of the disease and highlight the roles of amino acids and lipids in AML metabolism. Furthermore, we point out the potential of the different metabolic effectors to be used as novel therapeutic targets.

Venetoclax in patients with acute myeloid leukemia refractory to hypomethylating agents-a multicenter historical prospective study

Patients with acute myeloid leukemia (AML) who progress after exposure to hypomethylating agents (HMA) have a dismal prognosis. We hypothesized that the addition of venetoclax, a BCL-2 inhibitor, to AML patients who previously failed HMA might overcome resistance. Adult patients (≥ 18 years) with AML were eligible if leukemia relapsed after, or was refractory to HMA. In general, in addition to venetoclax, patients continued HMA or other low-intensity therapies. Patients who previously underwent allogeneic hematopoietic cell transplantation (HCT) were also eligible. Data were analyzed in November 2018. Twenty-three patients were treated between October 2016 and October 2018 and were eligible for this study. Median age was 76 years and 6 patients had leukemia that relapsed post allogeneic HCT. None of the patients experienced tumor lysis syndrome and toxicities were as expected and manageable. Febrile neutropenia was the most common toxicity (78% of patients). Median hospitalization time was 13 days. Forty-three percent of the patients achieved CR/CRi. Overall survival (OS) was 74% at 6 months and median OS in patients who achieved remission was 10.8 months. Higher number of blasts in both bone marrow and peripheral blood was associated with lower chances of CR, while higher WBC, LDH, and bone marrow or peripheral blasts were associated with increased mortality rate. The addition of venetoclax to patients with HMA-refractory AML may result in a substantial anti-leukemic activity, specifically in those achieving complete remission. This should be further tested in a well-designed prospective trial.

Clonal Hematopoiesis and risk of Acute Myeloid Leukemia

Acute Myeloid Leukemia, the most common form of acute leukemia in adults, is an aggressive hematopoietic stem cell malignancy that is associated with significant morbidity and mortality. Though AML generally presents de novo, risk factors include exposure to chemotherapy and/or radiation, as well as both familial and acquired bone marrow failure syndromes. Clonal Hematopoiesis (CH) refers to an expansion of blood or marrow cells resulting from somatic mutations in leukemia-associated genes detected in individuals without cytopenias or hematological malignancies. While CH is considered part of normal ageing, CH is also significantly associated with cardiovascular disease, solid tumors, and hematological malignancies. In this review, we will discuss evidence linking CH with the development of AML, as well as describe challenges in and strategies for monitoring patients with high risk CH mutations.

Importance of prognostic stratification via gene mutation analysis in elderly patients with acute myelogenous leukemia

INTRODUCTION

Acute myelogenous leukemia (AML) in elderly patients is associated with an increased incidence of complications and treatment-related toxicity because of the frequency of comorbid disease and age-related deterioration in organ function. Despite advances in AML treatment in recent years, elderly patients have experienced limited benefit, and their outcomes remain poor. This study aimed to perform a comprehensive gene mutation analysis in elderly AML patients and identify gene mutations that could serve as prognostic factors.

METHODS

An analysis of gene mutations was performed for 281 AML patients, including 98 elderly patients aged 65 years or above.

RESULTS

Compared to younger AML patients, elderly patients showed a higher frequency of the following gene mutations: TP53 (P = 0.026), PTPN11 (P = 0.006), RUNX1 (P = 0.024), TET2 (P = 0.002), and ASXL1 (P = 0.023). The complete remission rate was significantly lower in DNMT3A mutation-positive cases (4.26%, P = 0.011) and TP53 mutation-positive cases (2.13%, P = 0.031) than in negative cases. The overall survival rate was significantly poorer in cases with FLT3-ITD (P = 0.003), DNMT3A (P = 0.033), or TP53 mutation (P < 0.001). Conversely, cases with PTPN11 mutation (P = 0.014) had a significantly more favorable prognosis. In multivariate analysis, FLT3-ITD (P = 0.011) and TP53 mutation positivity (P = 0.002) were independent poor prognostic factors, as were a performance status of 3 or above (P < 0.001) and poor cytogenetic prognosis (P = 0.001). In contrast, PTPN11 mutation positivity (P = 0.023) was an independent favorable prognosis factor.

CONCLUSION

Analysis of gene mutations in elderly AML patients is very important, not only for establishing prognosis, but also for introducing appropriate molecular-targeted treatments.

Azacitidine maintenance after intensive chemotherapy improves DFS in older AML patients

The prevention of relapse is the major therapeutic challenge in older patients with acute myeloid leukemia (AML) who have obtained a complete remission (CR) on intensive chemotherapy. In this randomized phase 3 study (HOVON97) in older patients (≥60 years) with AML or myelodysplastic syndrome with refractory anemia with excess of blasts, in CR/CR with incomplete hematologic recovery (CRi) after at least 2 cycles of intensive chemotherapy, we assessed the value of azacitidine as postremission therapy with respect to disease-free survival (DFS; primary end point) and overall survival (OS; secondary end point). In total, 116 eligible patients were randomly (1:1) assigned to either observation (N = 60) or azacitidine maintenance (N = 56; 50 mg/m2, subcutaneously, days 1-5, every 4 weeks) until relapse, for a maximum of 12 cycles. Fifty-five patients received at least 1 cycle of azacitidine, 46 at least 4 cycles, and 35 at least 12 cycles. The maintenance treatment with azacitidine was feasible. DFS was significantly better for the azacitidine treatment group (logrank; P = .04), as well as after adjustment for poor-risk cytogenetic abnormalities at diagnosis and platelet count at randomization (as surrogate for CR vs CRi; Cox regression; hazard ratio, 0.62; 95% confidence interval, 0.41-0.95; P = .026). The 12-month DFS was estimated at 64% for the azacitidine group and 42% for the control group. OS did not differ between treatment groups, with and without censoring for allogeneic hematopoietic cell transplantation. Rescue treatment was used more often in the observation group (n = 32) than in the azacitidine maintenance group (n = 9). We conclude that azacitidine maintenance after CR/CRi after intensive chemotherapy is feasible and significantly improves DFS. The study is registered with The Netherlands Trial Registry (NTR1810) and EudraCT (2008-001290-15).

Hypomethylating agents in relapsed and refractory AML: outcomes and their predictors in a large international patient cohort

Although hypomethylating agents (HMAs) are frequently used in the frontline treatment of older acute myeloid leukemia (AML) patients, little is known about their effectiveness in relapsed or primary treatment-refractory (RR)-AML. Using an international multicenter retrospective database, we studied the effectiveness of HMAs in RR-AML and evaluated for predictors of response and overall survival (OS). A total of 655 patients from 12 centers received azacitidine (57%) or decitabine (43%), including 290 refractory (44%) and 365 relapsed (56%) patients. Median age at diagnosis was 65 years. Best response to HMAs was complete remission (CR; 11%) or CR with incomplete count recovery (CRi; 5.3%). Additionally, 8.5% experienced hematologic improvement. Median OS was 6.7 months (95% confidence interval, 6.1-7.3). As expected, OS differed significantly by best response, with patients achieving CR and CRi having a median OS of 25.3 and 14.6 months, respectively. In multivariate analysis, the presence of ≤5% circulating blasts and a 10-day schedule of decitabine were associated with improved response rates, whereas the presence of >5% circulating blasts and >20% bone marrow blasts were associated with decreased OS. A significant subset of RR-AML patients (16%) achieved CR/CRi with HMAs and experienced a median OS of 21 months. Outside of a clinical trial, HMAs represent a reasonable therapeutic option for some patients with RR-AML.

[Age-related clinical characteristics and prognosis in non-senile adults with acute myeloid leukemia]

目的

探讨非老年成人初发急性髓系白血病（AML）患者年龄相关的临床特征、早期治疗反应和预后。

方法

回顾性分析2008年1月至2017年12月收治的18~65岁初发AML（非急性早幼粒细胞白血病）连续病例，分析不同年龄组患者初诊时疾病特征、早期治疗反应、复发和生存，以及相关影响因素。

结果

共收集1 097例患者，男性591例（53.9%），中位年龄42岁。随着年龄的增长，患者WBC显著下降（P=0.003)，PLT显著上升（P=0.034），骨髓原始细胞比例显著下降（P=0.021）。SWOG危险度在各年龄组的分布差异无统计学意义（P=0.063）。NPM1阳性伴FLT3-ITD阴性的患者比例随年龄增长显著上升（P<0.001)。多因素分析显示，在总人群中，年龄增加是获得形态学无白血病状态（MLFS）（P=0.053）、完全缓解（CR）（P=0.004）和总生存（OS）（P=0.070）的不利影响因素，但在接受标准诱导治疗的患者中，年龄增加仅与CR相关（P=0.075），而与MLFS和OS无关。

结论

非老年初发AML患者的临床、细胞遗传学和分子学特征随年龄变化而不同。在接受标准诱导治疗的患者中，年龄增加与获得MLFS和OS均无显著相关性。

Myelodysplastic syndromes and acute myeloid leukemias in the elderly

Most patients above 60 years with acute myeloid leukemia (AML) will die from their disease. Nevertheless, the treatment concepts in elderly patients with myelodysplastic syndromes (MDS) and AML are rapidly evolving. A number of recent reports have identified better survival rates with intensive induction chemotherapy for patients up to 80 years, with the exception of patients with unfavorable genomic risk abnormalities or with major co-morbidities. Gemtuzumab ozogamicin is increasingly added to induction therapy for AML patients up to 70 years with favorable or intermediate risk profile, and Midostaurin for patients with a FLT3 mutation. The recommended dose of daunorubicin is 60 mg/m² for 3 + 7 induction therapy. Elderly patients with acute promyelocytic leukemia should receive all-trans retinoic acid and arsenic trioxide, and cytotoxic treatment is limited upfront to patients with initial leukocytosis. Allogeneic transplantation can be recommended to selected patients up to 70-75 years. For patients unfit for intensive treatment, therapeutic options comprise a hypomethylating agent (HMA), low-dose cytarabin and supportive care. HMA treatment is also increasingly applied for relapsed/refractory AML after intensive chemotherapy. A considerable number of candidate compounds are currently being studied in older AML patients, with their potential role in the treatment of elderly AML patients remaining to be clarified.

Improved Survival by Adding Lomustine to Conventional Chemotherapy for Elderly Patients With AML Without Unfavorable Cytogenetics: Results of the LAM-SA 2007 FILO Trial

Purpose

Acute myeloid leukemia (AML) in elderly patients has a poor prognosis. In an attempt to improve outcome for these patients, the prospective open-label phase III LAM-SA 2007 (Adding Lomustine to Chemotherapy in Older Patients With Acute Myelogenous Leukemia (AML), and Allogeneic Transplantation for Patients From 60 to 65 Years Old) trial randomly assigned patients to a standard induction regimen with lomustine added or to a consolidation regimen with cytarabine and idarubicin.

Patients and Methods

Adults age 60 years or older with previously untreated AML who were fit to receive intensive chemotherapy and who were without unfavorable cytogenetics received standard chemotherapy with lomustine (idarubicin, cytarabine, and lomustine [ICL]) or without (idarubicin and cytarabine [IC]). The primary objective of the study was overall survival (OS); secondary objectives were response rate, cumulative incidence of relapse (CIR), event-free survival (EFS), and safety.

Results

From February 2008 to December 2011, 459 patients were enrolled. Comparing patients in the IC and ICL arms, complete response or complete response with incomplete recovery was achieved in 74.9% versus 84.7% ( P = .01). The proportional hazards assumption was rejected for OS ( P = .02), which led us to consider two separate time intervals: during and after induction. There was no significant difference between the two arms during induction, although induction deaths were 3.7% versus 7.7%, respectively ( P = .11). However, significantly better results were observed after induction with an improved 2-year OS of 56% in the ICL arm versus 48% in the IC arm ( P = .02). At 2 years, EFS was improved at 41% in the ICL arm versus 26% in the IC arm ( P = .01). The CIR at 2 years was 41.2% in the ICL arm versus 60.9% in the IC arm ( P = .003). Grade 3 and 4 toxicities, mostly hematologic, were significantly higher in the ICL arm ( P = .04), and fewer patients required a second treatment after ICL.

Conclusion

Adding lomustine to standard chemotherapy significantly improved the outcome of elderly patients with AML.

Deferasirox selectively induces cell death in the clinically relevant population of leukemic CD34+CD38- cells through iron chelation, induction of ROS, and inhibition of HIF1α expression

Despite a high remission rate after therapy, only 40-50% of acute myeloid leukemia (AML) patients survive 5 years after diagnosis. The main cause of treatment failure is thought to be insufficient eradication of CD34⁺CD38^- AML cells. In order to induce preferential cell death in CD34⁺CD38^- AML cells, two separate events may be necessary: (1) inhibition of survival signals such as nuclear factor kappa-beta (NF-κB) and (2) induction of stress responses such as the oxidative stress response. Therefore, regimens that mediate both effects may be favorable. Deferasirox is a rationally designed oral iron chelator mainly used to reduce chronic iron overload in patients who receive long-term blood transfusions. Our study revealed that clinically relevant concentrations of deferasirox are cytotoxic in vitro to AML progenitor cells, but even more potent against the more primitive CD34⁺CD38^- cell population. In addition, we found that deferasirox exerts its effect, at least in part, by inhibiting the NF-κB/hypoxia-induced factor 1-alpha (HIF1α) pathway and by elevating reactive oxygen species levels. We believe that, pending further characterization, deferasirox can be considered as a potential therapeutic agent for eradicating CD34⁺CD38^- AML cells.

RAS mutations in acute myeloid leukaemia patients: A review and meta-analysis

RAS oncogene mutations frequently occur in acute myeloid leukaemia (AML), but the prognostic significance of RAS mutations in AML is inconclusive. We searched the databases of PubMed, Web of Science, EMBASE, and Cochrane from 1990 to 2018. In this study, 24 eligible studies were included, and the meta-analysis was conducted with the Comprehensive Meta-Analysis Version 2 software program. The row hazard ratio (HR) was adjusted and re-evaluated when publication bias existed after detecting all the heterogeneities. A combined analysis showed that RAS mutations were not associated with a poor prognosis in general AML patients (HR: 0.96, 95% CI: 0.78-1.19, p = 0.70). To further verify the results, a subgroup analysis was conducted. Interestingly, in the analysis of age bracket, children with RAS mutations had an unfavourable survival (HR: 1.35, 95% CI: 1.05-1.75, p = 0.02) of AML, but the adults did not (HR: 0.87, 95% CI: 0.70-1.09, p = 0.21). Further analysis of the subgroup of children indicated that patients with NRAS mutations had an adverse prognosis (HR: 1.55, 95% CI: 1.13-2.12, p = 0.007), but not those with KRAS mutations (HR: 1.51, 95% CI: 0.34-6.73, p = 0.59). In conclusion, this study revealed that RAS mutations did not influence the over survival for adults with AML. However, NRAS mutations may be a key prognostic marker related with poor survival for children with AML.

Acute myelogenous leukemia in adolescents and young adults

The incidence of acute myelogenous leukemia (AML) increases progressively with age. Favorable genetic mutations are most prevalent in children, and unfavorable profiles increase proportionately in adolescents and young adults (AYA) and into later adulthood. Survival rates of AYA have improved over recent decades to 50-60%, but their accrual to clinical trials remains poor. In contrast to AYA with acute lymphoblastic leukemia, the prognostic benefit for AYA with AML enrolled in pediatric compared with adult trials is minor and only seen when different protocols are used. The distinctive needs of AYA, including intensive psychological services, call for their treatment within specialized centers that offer complex supportive care.

Increased optical pathlength through aqueous media for the infrared microanalysis of live cells

The study of live cells using Fourier transform infrared spectroscopy (FTIR) and FTIR microspectroscopy (FT-IRMS) intrinsically yields more information about cell metabolism than comparable experiments using dried or chemically fixed samples. There are, however, a number of barriers to obtaining high-quality vibrational spectra of live cells, including correction for the significant contributions of water bands to the spectra, and the physical stresses placed upon cells by compression in short pathlength sample holders. In this study, we present a water correction method that is able to result in good-quality cell spectra from water layers of 10 and 12 μm and demonstrate that sufficient biological detail is retained to separate spectra of live cells based upon their exposure to different novel anti-cancer agents. The IR brilliance of a synchrotron radiation (SR) source overcomes the problem of the strong water absorption and provides cell spectra with good signal-to-noise ratio for further analysis. Supervised multivariate analysis (MVA) and investigation of average spectra have shown significant separation between control cells and cells treated with the DNA cross-linker PL63 on the basis of phosphate and DNA-related signatures. Meanwhile, the same control cells can be significantly distinguished from cells treated with the protein kinase inhibitor YA1 based on changes in the amide II region. Each of these separations can be linked directly to the known biochemical mode of action of each agent.

Incidence and survival of hematological cancers among adults ages ≥75 years

Evaluating population-based data of hematologic malignancies (HMs) in older adults provides prognostic information for this growing demographic. Incidence rates and one- and five-year relative survival rates were examined for specific HMs among adults ages ≥75 years using data from the Surveillance, Epidemiology and End Results (SEER) Program. Hematologic malignancy cases (Hodgkin lymphoma (HL), non-Hodgkin lymphoma (NHL), multiple myeloma (MM), acute lymphocytic leukemia (ALL), chronic lymphocytic leukemia (CLL), acute myeloid leukemia (AML), and chronic myeloid leukemia (CML)) were reported to one of 18 SEER registries. Recent average annual (2010-2014) incidence rates and incidence trends from 1973 to 2014 were examined for cases ages ≥75 years. One- and five-year relative cancer survival rates were examined for adults ages ≥75 years diagnosed 2007-2013, with follow-up into 2014. From 1973 to 2014, incidence rates increased for NHL, MM, and AML, decreased for HL, and remained relatively stable for ALL, CLL, and CML among adults ages ≥75 years. The highest one- and five-year relative survival rates were observed among adults with CLL ages 75-84 years (1 year: 91.8% (95% CI = 91.8-90.8)) and 5 years: 76.5% (95% CI = 74.2-78.6)). The lowest one- and five-year survival rates were observed among adults with AML ages 75-84 (1 year: 18.2% (95% CI = 74.2-78.6) and 5 years: 2.7% (95% CI = 2.0-3.6)). Survival for older adults ages ≥75 years with HMs is poor, particularly for acute leukemia. Understanding the heterogeneity in HM outcomes among older patients may help clinicians better address the hematological cancer burden and mortality in the aging population.

Economic burden of elderly patients with acute myeloid leukemia treated in routine clinical care in the United States

This retrospective claims database study examined healthcare utilization (HCU) and costs associated with acute myeloid leukemia (AML) in 237 elderly patients who received chemotherapy or a stem cell transplant (SCT) following AML diagnosis. Patients with secondary AML were excluded. Over the entire follow-up period, 92.0% of patients had ≥1 inpatient admission; 85.7% had ≥1 AML-related admission, and 42.6% had ≥1 non-AML-related admission. During inpatient admissions, 39.2% of patients had ≥1 intensive care unit (ICU) admission, with 20.7% having ≥1 AML-related ICU admission, and 27.8% having ≥1 non-AML-related ICU admission. Total mean per-patient per-month (PPPM) costs over the follow-up period were $25,243 (SD: $21,909), with costs from Year 1 ($27,756 [SD: $22,121]) more than double those in Year 2 ($12,953 [SD: $26,334]) following AML diagnosis. The majority of total costs were medical ($24,512 PPPM [SD: $21,704]), which included inpatient admissions ($6548 PPPM [SD: $10,777]), other outpatient visits ($5021 PPPM [SD: $7997]), supportive care ($3640 PPPM [SD: $5589], and chemotherapy administration ($2029 PPPM [SD: $2345]). Healthcare costs of treated elderly AML patients are substantial, particularly in the first year following diagnosis. Further research is needed to understand factors contributing to high costs in various settings of care for elderly AML patients.

Prognostic markers in core-binding factor AML and improved survival with multiple consolidation cycles of intermediate-/high-dose cytarabine

OBJECTIVES

Core-binding factor acute myeloid leukaemia (CBF AML) defined by t(8;21)(q22;q22) or inv(16)(p13q22)/t(16;16)(p13;q22) has a favourable prognosis; however, 30%-40% of patients still relapse after chemotherapy. We sought to evaluate the risk factors for relapse in a de novo CBF AML cohort.

PATIENTS/MATERIALS/METHODS

A retrospective review of patients from four Australian tertiary centres from 2001 to 2012, comprising 40 t(8;21) and 30 inv(16) AMLs.

RESULTS

Multivariate analysis identified age (P = .032) and white cell count (WCC)>40 (P = .025) as significant predictors for inferior OS and relapse, respectively. Relapse risk was higher in the inv(16) group vs the t(8;21) group (57% vs 18%, HR 4.31, 95% CI: 1.78-10.42, P = .001). Induction therapy had no bearing on OS or relapse-free survival (RFS); however, consolidation treatment with >3 cycles of intermediate-/high-dose cytarabine improved OS (P = .035) and RFS (P = .063). Five patients demonstrated post-treatment stable q PCR positivity without relapse.

CONCLUSIONS

>3 consolidation cycles of intermediate-/high-dose cytarabine improves patient outcomes Age and inv(16) CBF AML subtype are predictors of inferior OS and RFS, respectively. Stable low-level MRD by qPCR does not predict relapse Similar OS in the inv(16) cohort compared to the t(8;21) cohort, despite a higher relapse rate, confirms salvageability of relapsed disease.

Risk factors for length of stay and charge per day differ between older and younger hospitalized patients with AML

Acute myeloid leukemia (AML) is associated with frequent hospitalizations. We evaluated factors associated with length of stay (LOS) and charge per day (CPD) for admissions in older (≥60 years) and younger patients (<60 years). We identified patients with ICD‐9‐CM codes for AML or myeloid sarcoma in the 2012 HCUP‐NIS. In separate models based on age, we examined patient (sex, race, income, insurance payer, chronic conditions, chemotherapy administration, death) and hospital (type, geography) characteristics. Multivariable negative binomial regression estimated factor effects on LOS and CPD using rate ratios, with HCUP‐NIS weights. In 43,820 discharges, LOS was longer in patients <60 than ≥60 (6.8 vs. 5.4 days). For patients <60, longer LOS was seen with more chronic conditions (RR = 1.10), Black race (RR = 1.16), chemotherapy (RR = 2.27), and geography; shorter LOS was associated with older age (RR = 0.93), Medicare (RR = 0.83), and hospital type. For patients ≥60, longer LOS associated with chronic conditions (RR = 1.07) and Asian race (RR = 1.33). Shorter LOS associated with older age (RR = 0.86), higher income (RR = 0.93), and hospital type. For patients <60, higher CPD associated with chronic conditions (RR = 1.05), death (RR = 1.93), and geography; lower CPD associated with increasing age (RR = 0.96), Medicaid (RR = 0.93), and rural hospitals (RR = 0.65). For patients ≥60, higher CPD associated with Medicare (RR = 1.05), more chronic conditions (RR = 1.02), younger age (RR = 1.1), west geography (RR = 1.37), death (RR = 1.45), and Hispanic race (RR = 1.15). We identify predictors for increased healthcare utilization in hospitalized patients with AML, which differ within age groups. Future efforts are needed to link utilization outcomes with clinical treatments and response.

Prognosis of Acute Myeloid Leukemia in the General Population: Data from Southern Switzerland

Aims and background

To evaluate the outcome of adult patients with de novo acute myeloid leukemia in the Italian-speaking part of Switzerland and to identify prognostic factors, time to progression and overall survival.

Methods and study design

Data of all adult patients diagnosed with acute myeloid leukemia from January 1984 to December 2003 were collected retrospectively. Univariate and multivariate analysis for time to progression and overall survival were performed.

Results

The incidence of acute myeloid leukemia in the adult population in southern Switzerland is 2.6/100,000 per year. Complete clinical and pathological data and follow-up information were available for 128 patients. The median age was 67 years (range, 18 to 94). The median follow-up was 97 months. Median overall survival was 6 months, with a 2-year overall survival of 16%. Median time to progression was 3 months. Thirty-five patients (median age, 80 years) were given best supportive care and/or palliative chemotherapy. The median survival in this subset was 2 months. Of the 93 patients treated with a curative intent, 48 were older than 60 years. The complete remission rate after induction chemotherapy was 80% for patients younger than 60 years and 31% for those older than 60 years (P <0.0001). Overall survival at 2 years was 40% and 12%, respectively (P <0.0005). The relapse rate was 61%, and only 28% of the patients who were given reinduction chemotherapy reached a second complete remission. Of the patients treated with curative intent, 52% were treated in a clinical trial. Their median age was significantly lower than those not included in a trial: 57 vs 66 years (P <00001). Patients treated in a trial had a significantly better prognosis than those not so treated (median survival, 12 vs 6 months). Patients treated with high-dose cytarabine as first-line therapy (given to 25 of 93 patients treated with a curative intent) had a better survival than those given standard cytarabine doses (P <0.0005). The outcome of the patients treated after 1993 was significantly better (P = 0.026) than that of the previously treated cohort. In multivariate analysis (not including cytogenetic data), only age (P = 0.005), performance status >1 (P = 0.001) and treatment given before/after 1993 (P = 0.044) were found to be independent prognostic factors for both overall survival and time to progression.

Conclusions

Most patients with acute myeloid leukemia are older than 60 years, and their outcome is still disappointing. For younger patients, the prognosis is better if they receive high-dose cytarabine as post-remission therapy and if they are treated in the setting of a clinical trial.

Phase I clinical study of RG7356, an anti-CD44 humanized antibody, in patients with acute myeloid leukemia

RG7356, a recombinant anti-CD44 immunoglobulin G1 humanized monoclonal antibody, inhibits cell adhesion and has been associated with macrophage activation in preclinical models. We report results of a phase I dose-escalation study of RG7356 in relapsed/refractory acute myeloid leukemia (AML).Eligible patients with refractory AML, relapsed AML after induction chemotherapy, or previously untreated AML not eligible for intensive chemotherapy were enrolled and received intravenous RG7356 at dosages ≤ 2400 mg every other week or ≤ 1200 mg weekly or twice weekly; dose escalation started at 300 mg.Forty-four patients (median age, 69 years) were enrolled. One dose-limiting toxicity occurred (grade 3 hemolysis exacerbation) after one 1200 mg dose (twice-weekly cohort). The majority of adverse events were mild/moderate. Infusion-related reactions occurred in 64% of patients mainly during cycle 1. Two patients experienced grade 3 drug-induced aseptic meningitis. Pharmacokinetics increased supraproportionally, suggesting a target-mediated drug disposition (TMDD) at ≥ 1200 mg. Two patients achieved complete response with incomplete platelet recovery or partial response, respectively. One patient had stable disease with hematologic improvement.RG7356 was generally safe and well tolerated. Maximum tolerated dose was not reached, but saturation of TMDD was achieved. The recommended dose for future AML evaluations is 2400 mg every other week.

DNA-hypomethylating agents as epigenetic therapy before and after allogeneic hematopoietic stem cell transplantation in myelodysplastic syndromes and juvenile myelomonocytic leukemia

Myelodysplastic syndrome (MDS) is a clonal bone marrow disorder, typically of older adults, which is characterized by ineffective hematopoiesis, peripheral blood cytopenias and risk of progression to acute myeloid leukemia. Juvenile myelomonocytic leukemia (JMML) is an aggressive myeloproliferative neoplasm occurring in young children. The common denominator of these malignant myeloid disorders is the limited benefit of conventional chemotherapy and a particular responsiveness to epigenetic therapy with the DNA-hypomethylating agents 5-azacytidine (azacitidine) or decitabine. However, hypomethylating therapy does not eradicate the malignant clone in MDS or JMML and allogeneic hematopoietic stem cell transplantation (HSCT) remains the only curative treatment option. An emerging concept with intriguing potential is the combination of hypomethylating therapy and HSCT. Possible advantages include disease control with good tolerability during donor search and HSCT preparation, improved antitumoral alloimmunity, and reduced risk of relapse even with non-myeloablative regimens. Herein we review the current role of pre- and post-transplant therapy with hypomethylating agents in MDS and JMML.

Evaluation of the European LeukemiaNet recommendations for predicting outcomes of patients with acute myeloid leukemia treated in low- and middle-income countries (LMIC): A Brazilian experience

BACKGROUND

Current results regarding treatment outcomes in acute myeloid leukemia (AML) point to significant differences between low- and middle-income countries (LMIC) and high-income countries (HIC). Excluding well-known socioeconomic issues, genetic markers important for prognosis have not been properly incorporated into the clinical practice so far and their usefulness outside of well-controlled clinical trials remain unknown.

METHODS

Here, we assessed the clinical significance of the European LeukemiaNet (ELN) recommendations in 196 consecutive patients with AML in a real-life setting. All patients were younger than 60 years of age (49% male) and treated with conventional chemotherapy for induction and consolidation in three Brazilian Institutions that well represent Brazilian geographic and socioeconomic diversity.

FINDINGS

Multivariable analysis showed that ELN recommendations had a slight association with complete remission achievement (odds ratio: 0.74, 95% confidence interval, CI: 0.53-1.01; P=0.06), but were independently associated with poor overall survival (OS) (hazard ratio, HR: 1.3, 95% CI: 1.1-1.54; P=0.002), disease-free survival (DFS) (HR: 1.42, 95% CI: 1.03-1.95; P=0.028) and event-free survival (EFS) (HR: 1.24, 95% CI: 1.06-1.47; P=0.007), considering initial leukocyte counts and age as confounders. ELN recommendations had no impact on cumulative incidence of relapse (P=0.09).

INTERPRETATION

Our results suggest that within the context of LMIC, the prognostic markers recommended by ELN may be useful to predict patient's clinical outcomes; however, the OS, DFS and EFS were shorter than the reported in Europe and US for the respective risk groups.

Vosaroxin in combination with decitabine in newly diagnosed older patients with acute myeloid leukemia or high-risk myelodysplastic syndrome

Vosaroxin is an anti-cancer quinolone-derived DNA topoisomerase II inhibitor. We investigated vosaroxin with decitabine in patients ≥60 years of age with newly diagnosed acute myeloid leukemia (n=58) or myelodysplastic syndrome (≥10% blasts) (n=7) in a phase II non-randomized trial. The initial 22 patients received vosaroxin 90 mg/m² on days 1 and 4 with decitabine 20 mg/m² on days 1–5 every 4–6 weeks for up to seven cycles. Due to a high incidence of mucositis the subsequent 43 patients were given vosaroxin 70 mg/m² on days 1 and 4. These 65 patients, with a median age of 69 years (range, 60–78), some of whom with secondary leukemia (22%), adverse karyotype (35%), or TP53 mutation (20%), are evaluable. The overall response rate was 74% including complete remission in 31 (48%), complete remission with incomplete platelet recovery in 11 (17%), and complete remission with incomplete count recovery in six (9%). The median number of cycles to response was one (range, 1–4). Grade 3/4 mucositis was noted in 17% of all patients. The 70 mg/m² induction dose of vosaroxin was associated with similar rates of overall response (74% versus 73%) and complete remission (51% versus 41%, P=0.44), reduced incidence of mucositis (30% versus 59%, P=0.02), reduced 8-week mortality (9% versus 23%; P=0.14), and improved median overall survival (14.6 months versus 5.5 months, P=0.007). Minimal residual disease-negative status by multiparametric flow-cytometry at response (± 3 months) was achieved in 21 of 39 (54%) evaluable responders and was associated with better median overall survival (34.0 months versus 8.3 months, P=0.023). In conclusion, the combination of vosaroxin with decitabine is effective and well tolerated at a dose of 70 mg/m² and warrants randomized prospective evaluation. ClinicalTrials.gov: NCT01893320

Activity cliff for 7-substituted pyrrolo-pyrimidine inhibitors of HCK explained in terms of predicted basicity of the amine nitrogen

We previously reported the structure-based design of a highly potent hematopoietic cell kinase (HCK) inhibitor, a pyrrolo-pyrimidine compound designated RK-20449, for treatment of recurrent leukemia. Herein we report the synthesis and structure-activity relationships of some amino acid derivatives of 7-substituted pyrrolo-pyrimidine. Although these derivatives had the same predicted binding conformation as RK-20449, their IC₅₀ values were 100-1000 times larger than that of the parent compound. We assumed that the basicity of the amine nitrogen, which formed an ionic bond with Asp348 of HCK, markedly affected inhibitory activity against HCK. The pKa values of the nitrogen were predicted by means of an ab initio quantum mechanical method, and complexes of the derivatives with HCK were analyzed by X-ray crystallography. We observed a significant correlation between the predicted pKa and IC₅₀ values, and the crystal structures of the less potent derivatives showed various types of defects around the ionic bond.

Probing the action of a novel anti-leukaemic drug therapy at the single cell level using modern vibrational spectroscopy techniques

Acute myeloid leukaemia (AML) is a life threatening cancer for which there is an urgent clinical need for novel therapeutic approaches. A redeployed drug combination of bezafibrate and medroxyprogesterone acetate (BaP) has shown anti-leukaemic activity in vitro and in vivo. Elucidation of the BaP mechanism of action is required in order to understand how to maximise the clinical benefit. Attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy, Synchrotron radiation FTIR (S-FTIR) and Raman microspectroscopy are powerful complementary techniques which were employed to probe the biochemical composition of two AML cell lines in the presence and absence of BaP. Analysis was performed on single living cells along with dehydrated and fixed cells to provide a large and detailed data set. A consideration of the main spectral differences in conjunction with multivariate statistical analysis reveals a significant change to the cellular lipid composition with drug treatment; furthermore, this response is not caused by cell apoptosis. No change to the DNA of either cell line was observed suggesting this combination therapy primarily targets lipid biosynthesis or effects bioactive lipids that activate specific signalling pathways.

Therapy of older persons with acute myeloid leukaemia

Most persons age≥60 y with acute myeloid leukaemia (AML) die from their disease. When interpreting clinical trials data from these persons one must be aware of substantial selection biases. Randomized trials of post-remission treatments can be performed upfront or after achieving defined landmarks. Both strategies have important limitations. Selection of the appropriate treatment is critical. Age, performance score, co-morbidities and frailty provide useful data to treatment selection. If an intensive remission induction therapy is appropriate, therapy with cytarabine and an anthracycline is the most common regimen. Non-intensive therapies consist of the hypo-methylating drugs azacitidine and decitabine, low-dose cytarabine and supportive care. Feasibility of doing an allotransplant in older persons with AML is increasing. However, only very few qualify. Results of cytogenetic testing are risk factor in young and old persons with AML. Adverse abnormalities are more frequent in older persons. Although data about the frequency of mutations in older persons with AML is increasing their prognostic impact is less clear than in younger subjects. Neither differences in the distribution of cytogenetic risk, mutations, nor differences in clinical risk factors between younger and older persons with AML completely explain the age-dependent outcome. Many drugs are in clinical development in older persons with AML. Their potential role in the treatment of older persons with AML remains to be defined.

UNC2025, a MERTK Small-Molecule Inhibitor, Is Therapeutically Effective Alone and in Combination with Methotrexate in Leukemia Models

Purpose: MERTK tyrosine kinase is ectopically expressed in 30% to 50% of acute lymphoblastic leukemias (ALL) and more than 80% of acute myeloid leukemias (AML) and is a potential therapeutic target. Here, we evaluated the utility of UNC2025, a MERTK tyrosine kinase inhibitor, for treatment of acute leukemia.Experimental Design: Preclinical in vitro and in vivo assays using cell lines and primary leukemia patient samples were used to evaluate antileukemic effects of UNC2025.Results: UNC2025 potently inhibited prosurvival signaling, induced apoptosis, and reduced proliferation and colony formation in MERTK-expressing ALL and AML cell lines and patient samples. Approximately 30% of primary leukemia patient samples (78 of 261 total) were sensitive to UNC2025. Sensitive samples were most prevalent in the AML, T-ALL, and minimally differentiated (M0) AML subsets. UNC2025 inhibited MERTK in bone marrow leukemia cells and had significant therapeutic effects in xenograft models, with dose-dependent decreases in tumor burden and consistent two-fold increases in median survival, irrespective of starting disease burden. In a patient-derived AML xenograft model, treatment with UNC2025 induced disease regression. In addition, UNC2025 increased sensitivity to methotrexate in vivo, suggesting that addition of MERTK-targeted therapy to current cytotoxic regimens may be particularly effective and/or allow for chemotherapy dose reduction.Conclusions: The broad-spectrum activity mediated by UNC2025 in leukemia patient samples and xenograft models, alone or in combination with cytotoxic chemotherapy, supports continued development of MERTK inhibitors for treatment of leukemia. Clin Cancer Res; 23(6); 1481-92. ©2016 AACR.

TET2 exon 2 skipping is an independent favorable prognostic factor for cytogenetically normal acute myelogenous leukemia (AML): TET2 exon 2 skipping in AML

In AML, approximately one-third of expressed genes are abnormally spliced, including aberrant TET2 exon 2 expression. In a discovery cohort (n=99), TET2 exon 2 skipping (TET2E2S) was found positively associated with a significant reduction in the cumulative incidence of relapse (CIR). Age, cytogenetics, and TET2E2S were independent prognostic factors for disease-free survival (DFS), and favorable effects on outcomes predominated in cytogenetic normal (CN)-AML and younger patients. Using the same cutoff in a validation cohort of 86 CN-AML patients, TET2E2S^high patients were found to be younger than TET2^low patients without a difference in the rate of complete remission. However, TET2E2S^high patients exhibited a significantly lower CIR (p<10^-4). TET2E2S and FLT3-ITD, but not age or NPM1 mutation status were independent prognostic factors for DFS and event-free survival (EFS), while TET2E2S was the sole prognostic factor that we identified for overall survival (OS). In both the intermediate-1 and favorable ELN genetic categories, TET2E2S remained significantly associated with prolonged survival. There was no correlation between TET2E2S status and outcomes in 34 additional AML patients who were unfit for IC. Therefore our results suggest that assessments of TET2 exon 2 splicing status might improve risk stratification in CN-AML patients treated with IC.

A comparison of clofarabine with ara-C, each in combination with daunorubicin as induction treatment in older patients with acute myeloid leukaemia

The study was designed to compare clofarabine plus daunorubicin vs daunorubicin/ara-C in older patients with acute myeloid leukaemia (AML) or high-risk myelodysplastic syndrome (MDS). Eight hundred and six untreated patients in the UK NCRI AML16 trial with AML/high-risk MDS (median age, 67 years; range 56-84) and normal serum creatinine were randomised to two courses of induction chemotherapy with either daunorubicin/ara-C (DA) or daunorubicin/clofarabine (DClo). Patients were also included in additional randomisations; ± one dose of gemtuzumab ozogamicin in course 1; 2v3 courses and ± azacitidine maintenance. The primary end point was overall survival. The overall response rate was 69% (complete remission (CR) 60%; CRi 9%), with no difference between DA (71%) and DClo (66%). There was no difference in 30-/60-day mortality or toxicity: significantly more supportive care was required in the DA arm even though platelet and neutrophil recovery was significantly slower with DClo. There were no differences in cumulative incidence of relapse (74% vs 68%; hazard ratio (HR) 0.93 (0.77-1.14), P=0.5); survival from relapse (7% vs 9%; HR 0.96 (0.77-1.19), P=0.7); relapse-free (31% vs 32%; HR 1.02 (0.83-1.24), P=0.9) or overall survival (23% vs 22%; HR 1.08 (0.93-1.26), P=0.3). Clofarabine 20 mg/m2 given for 5 days with daunorubicin is not superior to ara-C+daunorubicin as induction for older patients with AML/high-risk MDS.

Frontline treatment of acute myeloid leukemia in adults

Recent years have highlighted significant progress in understanding the underlying genetic and epigenetic signatures of acute myeloid leukemia(AML). Most importantly, novel chemotherapy and targeted strategies have led to improved outcomes in selected genetic subsets. AML is a remarkably heterogeneous disease, and individualized therapies for disease-specific characteristics (considering patients' age, cytogenetics, and mutations) could yield better outcomes. Compared with the historical 5-to 10-year survival rate of 10%, the survival of patients who undergo modern treatment approaches reaches up to 40-50%, and for specific subsets, the improvements are even more dramatic; for example, in acute promyelocytic leukemia, the use of all-trans retinoic acid and arsenic trioxide improved survival from 30 to 40% up to 80 to 90%. Similar progress has been documented in core-binding-factor-AML, with an increase in survival from 30% to 80% upon the use of high-dose cytarabine/fludarabine/granulocyte colony-stimulating factor combination regimens. AML treatment was also recently influenced by the discovery of the superiority of regimens with higher dose Ara-C and nucleoside analogues compared with the "7+3"regimen, with about a 20% improvement in overall survival. Despite these significant differences, most centers continue to use the "7+3" regimen, and greater awareness will improve the outcome. The discovery of targetable molecular abnormalities and recent studies of targeted therapies (gemtuzumab ozagomycin, FLT3 inhibitors, isocitrate dehydrogenase inhibitors, and epigenetic therapies), future use of checkpoint inhibitors and other immune therapies such as chimeric antigen receptor T-cells, and maintenance strategies based on the minimal residual disease evaluation represent novel, exciting clinical leads aimed to improve AML outcomes in the near future.

Mutations in AML: prognostic and therapeutic implications

Acute myeloid leukemia (AML) is a heterogeneous hematologic malignancy characterized by the proliferation and aberrant differentiation of immature clonal myeloid cells. The prognosis of AML is variable, based on clinical features such as patient age, performance status, and comorbidities, as well as leukemia-specific genetic features including cytogenetics and molecular classification. The modern application of next-generation sequencing technology has uncovered marked heterogeneity and genomic complexity within AML, based on the presence or absence of cooperating mutations within functional categories such as epigenetic regulators, cell signaling and proliferation pathways, and master hematopoietic transcription factors. Although the treatment of AML has hitherto changed little in the past 40 years, the enhanced scientific understanding of AML pathophysiology and leukemogenesis has led to the recent development of multiple targeted and selective treatment approaches, and our increasing awareness of functional AML subsets will be evermore used to inform rational and personalized treatment strategies.

Efficacy of Azacitidine in the treatment of adult patients aged 65 years or older with AML

INTRODUCTION

Therapy for acute myeloid leukemia (AML) in elderly populations (>65 years) is still a challenge for scientists and hematologists worldwide, and represents an urgent medical need. Notably, the identification and the recognition of molecular and epigenetic mechanisms involved in the pathogenesis of such a heterogeneous disease, are providing new tools for a more successful and 'targeted' approach. Azacitidine is a hypomethylating agent (HMA) with relevant activity in patients affected by myelodysplastic syndrome (MDS) and AML with low blast cells percentage (>30%), in terms of reduction of transfusion dependence, and improvement of quality of life. Areas covered: This review summarizes the mechanism of action, safety profile and efficacy of azacitidine in the field of elderly AML populations, providing up-to-date references on this subset of high-risk patients. Expert opinion: HMAs are the first successful treatment for elderly patients with high-risk MDS and are effective for some AML subtypes. Translational studies based on gene expression profiling and molecular sequencing, would be able to identify, in the near future, patients with a favorable profile of response to these compounds suggesting new potential treatment combinations also.

Selecting initial treatment of acute myeloid leukaemia in older adults

More than half of the patients with acute myeloid leukaemia (AML) are older than 60years. The treatment outcomes in this group remain poor with a median overall survival of <1year. Selecting initial treatment for these patients involves an assessment of 'fitness' for induction chemotherapy. This is done based on patient and disease-related characteristics which help to estimate treatment-related mortality and chance of complete remission with induction chemotherapy. If the risk of treatment-related mortality is high and/or the likelihood of a patient achieving a complete remission is low, lower-intensity treatment (low-dose cytarabine, decitabine and azacitidine) should be discussed. As outcomes in both groups of patients remain poor, enrolment into clinical trials of novel agents with varying mechanisms of action should be considered for all older adults with AML. Novel agents in Phase III development include CPX-351, guadecitabine (SGI-110), quizartinib, crenolanib, sapacitabine, vosaroxin and volasertib.

A Phase I Dose Escalation Study of the Triple Angiokinase Inhibitor Nintedanib Combined with Low-Dose Cytarabine in Elderly Patients with Acute Myeloid Leukemia

Nintedanib (BIBF 1120), a potent multikinase inhibitor of VEGFR-1/-2/-3, FGFR-1/-2/-3 and PDGFR-α/-β, exerts growth inhibitory and pro-apoptotic effects in myeloid leukemic cells, especially when used in combination with cytarabine. This phase I study evaluated nintedanib in combination with low-dose cytarabine (LDAC) in elderly patients with untreated or relapsed/refractory acute myeloid leukemia (AML) ineligible for intensive chemotherapy in a 3+3 design. Nintedanib (dose levels 100, 150, and 200 mg orally twice daily) and LDAC (20 mg subcutaneous injection twice daily for 10 days) were administered in 28-day cycles. Dose-limiting toxicity (DLT) was defined as non-hematological severe adverse reaction CTC grade ≥ 4 with possible or definite relationship to nintedanib. Between April 2012 and October 2013, 13 patients (median age 73 [range: 62-86] years) were enrolled. One patient did not receive study medication and was replaced. Nine (69%) patients had relapsed or refractory disease and 6 (46%) patients had unfavorable cytogenetics. The most frequently reported treatment-related adverse events (AE) were gastrointestinal events. Twelve SAEs irrespective of relatedness were reported. Two SUSARs were observed, one fatal hypercalcemia and one fatal gastrointestinal infection. Two patients (17%) with relapsed AML achieved a complete remission (one CR, one CRi) and bone marrow blast reductions without fulfilling PR criteria were observed in 3 patients (25%). One-year overall survival was 33%. Nintedanib combined with LDAC shows an adequate safety profile and survival data are promising in a difficult-to-treat patient population. Continuation of this trial with a phase II recommended dose of 2 x 200 mg nintedanib in a randomized, placebo-controlled phase II study is planned. The trial is registered to EudraCT as 2011-001086-41.

TRIAL REGISTRATION

ClinicalTrials.gov NCT01488344.

Spectrum and prognostic relevance of driver gene mutations in acute myeloid leukemia

We present comprehensive information on genetic driver events in a uniformly treated cohort of 664 adult AML patients aged 18 to 86 years. Mutations in NPM1, FLT3, CEBPA, TP53, and, in patients <60 years, DNMT3A and RUNX1, are the most important molecular risk factors in AML.

Management of Newly Diagnosed Acute Myeloid Leukemia in the Elderly: Current Strategies and Future Directions

The incidence of acute myeloid leukemia (AML) increases with age, and the majority of cases occur in adults aged >55 years. The prognosis of AML in older adults is generally poor; however, AML is a heterogeneous disease regardless of age, and prognosis depends on cytogenetic changes, genetic mutations, and patient characteristics. Several lines of evidence support offering treatment to the vast majority of older patients, and the survival benefit associated with this approach generally outweighs the risk of toxicity. Response and long-term survival using intensive induction regimens are significantly lower in older patients, although a small proportion of patients can achieve durable remissions. Selection of patients for intensive induction therapy requires comprehensive assessment of disease characteristics, performance status, and comorbidities. In unfit patients, options for treatment include hypomethylating agents, low-dose ara-C, or consideration of a clinical trial if available. The incorporation of novel therapies into treatment, such as FLT3 inhibitors and antibody-drug conjugates, offers significant promise in older patients, although, thus far, increased responses using novel agents have often not translated to improved survival outcomes. The development of reduced-intensity conditioning regimens and improvements in supportive care has increased the use of allogeneic stem cell transplant (ASCT) in older patients. Selection of patients for ASCT requires an estimation of the trade-off between toxicity and risk of relapse.

The outcome and prognostic factors of 248 elderly patients with acute myeloid leukemia treated with standard-dose or low-intensity induction therapy

The prognosis of elderly patients with acute myeloid leukemia (AML) is poor, and the recommendation of standard-dose or low-intensity induction regimen for these patients remains controversial. We retrospectively analyzed treatment outcome and prognostic factors of elderly AML patients who had received either standard-dose or low-intensity induction regimens.Two hundred forty-eight elderly AML patients with good Eastern Cooperative Oncology Group performance status (ECOG PS ≤ 2) received one of three regimens for induction in this study: standard-dose cytarabine plus idarubicin (IA; n = 144) or daunorubicin (DA; n = 42); low-intensity cytarabine, aclarubicin, and granulocyte colony-stimulating factor (G-CSF) (CAG; n = 62).After first induction treatment cycle, the overall complete remission (CR) rate was 42.7%. Patients in IA group had a higher CR rate than in DA or CAG group (49.3%, 35.7%, and 32.3%, respectively; P = 0.046). The 1-year, 3-year, and 5-year overall survival (OS) rates were 42.2%, 18.9%, and 13.5% for these 248 patients, with median survival of 9.2 months. Long-term survival of IA group was better than DA or CAG group. The 1-year, 3-year, and 5-year OS rates of IA group were 45.9%, 23.5%, and 19.4%, respectively, as compared to 39.8%, 8.3%, and estimated 2.4% in DA group, and 34.9%, 15.9%, and 6.3% in CAG group, respectively. Early induction mortality and 2-year relapse rates showed no difference among 3 groups. Univariate analysis and multivariate analysis identified lactic dehydrogenase (LDH) more than two times of upper normal limit at diagnosis and nonremission after first induction cycle as adverse prognostic factors for OS. A simple and valid scoring model was constructed for risk stratification and prediction of long-term survival of elderly AML patients.Standard-dose IA regimen could improve the prognosis of elderly AML patients with good performance status compared with standard-dose DA or low-intensity CAG regimen. All prognostic factors and risk assessment should be considered to ensure that each patient receives the suitable individualized treatment.

Prevalence and Clinical Significance of FLT3 Mutation Status in Acute Myeloid Leukemia Patients: A Multicenter Study

BACKGROUND AND AIMS

FLT3-ITD mutations in acute myeloid leukemia (AML) are associated with a poor prognosis. In Latin America, little epidemiological data exist about these mutations and their influence on clinical evolution and prognosis. Standardization and well-established clinical correlation make FLT3 mutational analysis by molecular methods an invaluable tool to decide among treatment options and to determine AML prognosis.

METHODS

We assessed the prevalence of FLT3-ITD mutations in 138 patients with AML at four hematology referral centers from Mexico and Colombia. Molecular methods based on polymerase chain reaction (PCR) were employed for determining FLT3-ITD status.

RESULTS

Mutations were present in 28 patients indicating a prevalence of 20.28%. Median age was 47 years (5-96). The FLT3 mutation positive group was older, had higher WBC and hemoglobin values and lower platelet counts but without statistical significance. A not previously described mutation in the FLT3 gene was found in one patient involving a nucleotide exchange of timine for cytosine at the 66608 position. A high mortality was found in the FLT3-mutated group, 67.8 vs. 42.72% in the non-mutated group and median survival was 4.9 months vs. 20.4 months, p = 0.009. A mutated FLT3 did not confer poor prognosis to those with M3 AML. The mutated FLT3 population had poor overall survival (OS) despite hematoprogenitor stem cell transplantation (HSCT).

CONCLUSION

Prevalence of FLT3-ITD mutation in AML was present in a proportion comparable to other populations and, when present, was associated with a very poor prognosis.