Acute Myelogenous Leukemia Patients Research Articles

Prognosis of vascular endothelial growth factor gene polymorphism in Egyptian patients with acute myeloid leukemia

BackgroundAngiogenesis is an important process in hematological malignancies especially leukemia. Its role in acute leukemia has been discussed since the cloning of the vascular endothelial growth factor (VEGF) gene from acute myelogenous leukemia (AML). HL-60 is a human promyelocytic leukemia cell line. VEGF, a polymorphic gene, plays a key role in angiogenesis and tumor growth. Its different genotypes are associated with many human diseases. Increased angiogenesis, mediated by VEGF, was associated with poor prognosis in AML patients. AML that arises from neoplastic transformation of hematopoietic stem and progenitor cells remains one of the greater challenges in treating this AML. In adults, leukemia is included in the top 15 of the most common forms of cancer. Single-nucleotide polymorphism of the VEGF gene, 699947 is found in peripheral blood mononuclear cells of Iranian, Australian, Caucasian, and African patients with AML. The main target of this study is to investigate the relationship between VEGF gene polymorphism (rs699947) with AML.Patients and methodsThis a controlled study which included 100 and 76 individuals in each group, respectively. Group 1: a healthy control group and group 2: AML diagnosed patients. Blood samples were genotyped using the tetra-primer amplification-refractory mutation system-PCR and the results were confirmed by PCR-restriction fragment length polymorphism method.ResultsOur results suggest that there is a correlation between rs699947 single-nucleotide polymorphism and AML development and prognosis. However, patients with −2578 AA/CC genotypes were associated with significant better complete remission in comparison to patients with −2578 CA genotype (P = 0.0001). We found that certain polymorphisms are associated significantly with remissions while others with worse response to induction chemotherapy.

1364. Effect of Cefepime Prophylaxis on Bacterial Bloodstream Infections in Neutropenic Patients with Acute Myelogenous Leukemia

BackgroundBacteremia is a major cause of morbidity and mortality among children with acute myelogenous leukemia (AML) and chemotherapy-induced neutropenia. Data evaluating the utility of bacterial prophylaxis in this pediatric population are limited. In April 2014, Children’s Health (CH) implemented the use of cefepime bacterial prophylaxis for AML patients undergoing induction and intensification chemotherapy. The objective of this study was to evaluate the impact of this practice on the frequency of documented bacterial bloodstream infections (BSIs).MethodsThis was an observational, retrospective cohort study of patients < 21 years of age with AML admitted at CH from January 2010 through December 2018. The primary outcome was frequency of documented BSIs before (PRE; Jan 2010 to Mar 2014) and after (POST; Apr 2014 to Dec 2018) implementation of routine bacterial prophylaxis. Secondary outcomes included differences in total antibiotic days per neutropenia days and the occurrence of neutropenia-associated C. difficile infection between groups.ResultsOf 90 patients with AML who met the cohort inclusion criteria, 38 and 52 were treated during the PRE and POST prophylaxis periods, respectively. The incidence rate of documented BSIs per 1000 neutropenia days decreased from 15.5 to 2.8 after the implementation of routine cefepime prophylaxis (incidence rate ratio 0.18, Poisson regression 95% CI 0.09 to 0.33, P< 0.001). Patients were more likely to have febrile neutropenia in the PRE group (OR 11.9, 95% CI 6.6 to 20.8). The POST group had more antibiotic days per total neutropenia days (0.76 PRE vs 0.97 POST, P< 0.0001), but the frequency of first-episode C. difficile infection was not significantly different between groups (OR 0.36, 95% CI 0.1 to 1.4).ConclusionUniversal cefepime prophylaxis for children with AML and chemotherapy-induced neutropenia was associated with a significant reduction in the incidence of febrile neutropenia and neutropenia-associated BSIs without increasing the incidence of C. difficile infection.Disclosures All Authors: No reported disclosures

Allogeneic Hematopoietic Stem Cell Transplantation Improved Survival for Adult Core Binding Factor Acute Myelogenous Leukemia Patients with Intermediate- and Adverse-Risk Genetics in the 2017 European LeukemiaNet

The use of allogeneic hematopoietic stem cell transplantation (allo-HSCT) for consolidation therapy in patients with core binding factor (CBF) acute myelogenous leukemia (AML) with intermediate- and adverse-risk genetics remains controversial. We retrospectively analyzed the clinical outcomes of 286 CBF-AML patients with intermediate- and adverse-risk genetics in first complete remission following consolidation with chemotherapy (n=122), auto-HSCT (n=27), or allo-HSCT (n=137) between January 2009 and December 2018 at our center. Patients with allo-HSCT showed superior 5-year overall survival (OS; 74% versus 38% or 49%; P < .001) and progression-free survival (PFS; 74% versus 26% or 49%; P < .001) and lower cumulative incidence of relapse (CIR; 9% versus 69% or 31%; P < .001) compared with chemotherapy alone or auto-HSCT. In the allo-HSCT group, minimal residual disease (MRD) at the second and third months after allo-HSCT could predict relapse in t(8;21) patients (2 months: PCIR=.002; 3 months: PCIR < .001) but not in inv(16) patients. Moreover, positive MRD after 2 courses of consolidation chemotherapy before allo-HSCT was an independent risk factor for survival in CBF-AML patients with intermediate- and adverse-risk genetics, whereas haploidentical donor (haplo-) HSCT could overcome the adverse prognosis (5-year OS, 87%; 5-year PFS, 81%; 5-year CIR, 7%). Allo-HSCT could be the optimal first-line consolidation therapy for patients with intermediate- and adverse-risk genetics, and haplo-HSCT could improve survival for patients with positive MRD after 2 courses of consolidation chemotherapy.

Expression of ERV3-1 in leukocytes of acute myelogenous leukemia patients.

Acute myelogenous leukemia (AML) is one of the major hematological malignancies. In the human genome, several have been found to originate from retroviruses, and some of which are involved in the progression of various cancers. Hence, to investigate whether retroviral-like genes are associated with AML development, we conducted a transcriptome sequencing analysis of 12 retroviral-like genes of 150 AML patients and 32 healthy donor samples, of which RNA sequencing data were obtained from public databases. We found high expression of ERV3-1, an envelope gene of endogenous retrovirus group 3 member 1, in all AML patients examined in this study. In particular, blood and bone marrow cells of the myeloid lineage in AML patients, exhibited higher expression of ERV3-1 than those of the monocytic AML lineage. We also examined the protein expression of ERV3-1 by immunohistochemical analysis and found expression of the ERV3-1 protein in all 12 myeloid-phenotype patients and 7 out of 12 monocytic-phenotype patients, with a particular concentration observed at the membrane of some leukemic cells. Transcriptome analysis further suggested that upregulated ERV3-1 expression may be associated with chromosome 8 trisomy as anomaly was found to be more common among the high expression group than the low expression group. However, this finding was not corroborated by the immunohistochemical data. This discrepancy may have been caused, in part, by the small number of samples analyzed in this study. Although the precise associated molecular mechanisms remain unclear, our results suggest that ERV3-1 may be involved in AML development.

Malignant Progenitors From Patients With Acute Myelogenous Leukemia Are Sensitive to a Diphtheria Toxin–Granulocyte-Macrophage Colony-Stimulating Factor Fusion Protein

AbstractWe have previously demonstrated that human granulocyte-macrophage colony-stimulating factor (GM-CSF) fused to a truncated diphtheria toxin (DT388-GMCSF) kills acute myelogenous leukemia (AML) cell lines bearing the GM-CSF receptor. We now report that exposure of malignant cells from 50 different patients with AML for 48 hours in culture to DT388-GMCSF reduces by a median of 1.6 logs (range, 0 to 3.7 logs) the number of leukemic cells capable of forming colonies in semisolid media (leukemic colony-forming cells [CFU-L]) with a median IC50 of 3 × 10−12 mol/L (range, 5 to >4,000 × 10−12 mol/L). Furthermore, the cell kill is dependent on the presence of high-affinity GM-CSF receptors on leukemic blasts, because CFU-L from 27 of 28 AML samples expressing ≥35 GM-CSF receptors per cell were inhibited by the toxin, whereas the colony growth from all 4 leukemic samples (2 AML, 1 acute lymphoblastic leukemia [ALL], and 1 prolymphocytic leukemia [PLL]) that had less than 35 receptors per cell was unaffected by the drug. Sensitivity of CFU-L to DT388-GMCSF was seen regardless of the clinical responsiveness of the patient's leukemia to standard chemotherapy agents. In contrast, clonogenic cells from normal bone marrow formed colonies at near control numbers after exposure to much higher toxin concentrations (4 × 10−9 mol/L) than those required to kill CFU-L from most patients. Thus, leukemic progenitors isolated directly from the peripheral blood of most AML patients show the same sensitivity to DT388-GMCSF as previously demonstrated for AML cell lines. Under the same conditions of exposure, normal hematopoietic progenitors are relatively unaffected by DT388-GMCSF, suggesting its potential as a therapeutic agent in AML.

Protein Energy Malnutrition Significantly Increases Mortality and Adverse Outcomes in Acute Myelogenous Leukemia (AML) Patients with Neutropenic Fever: Findings of a Nationwide Inpatient Sample Analysis

Introduction: Neutropenic fever is a major cause of morbidity and mortality in all malignancies, especially acute leukemia. Protein energy malnutrition (PEM) is also a well-established risk factor for overall cancer related mortality. Acute myelogenous leukemia (AML) patients are frequently afflicted with neutropenic fever due to protracted neutropenia and community acquired, nosocomial, and opportunistic infections. They are also commonly malnourished due to poor oral intake, cachexia from underlying disease, and the toxicity of chemotherapy. To date, few studies have attempted to link neutropenic fever and PEM outcomes in AML. We thus aim to explore the prevalence and outcome of PEM in patients with AML and neutropenic fever. Methods: The Nationwide Inpatient Sample (NIS) database for 2016 and 2017 was searched for patients with primary discharge diagnosis of AML who had NF. This group was divided based on the presence or absence of PEM. The primary outcome was a comparison of inpatient mortality between the groups. Secondary outcomes included diagnosis of sepsis, mean total hospital charges (THC) and mean length of hospital stay (LOS). Outcomes were compared using multivariate regression analysis adjusting for sociodemographic and hospital characteristics and Charlson comorbidity index as a marker of severity. Results: A total of 10145 admissions met the inclusion criteria with AML and NF. Among the included patients, 1700 (16.7%) had PEM. Patient with PEM were significantly older (58.1 vs 55.2 years of age, p&amp;lt;0.001) but had no significant difference in sex (52.0 vs 55.0% females, p=0.308) and racial distribution, compared with patients without PEM. Overall, 825 (8.1%) hospitalizations had inpatient mortality. Patients with PEM had significantly higher adjusted odds ratio (aOR) of mortality (aOR: 2.00, 95% CI 1.335 - 2.998), developing sepsis (aOR: 2.06, 95% CI 1.514 - 2.812), as well as increase mean difference in LOS(8.6 days, 95% CI 5.77 - 11.37) and THC (105,600 USD 95% CI 57,000 - 154,000), compared to patients without PEM. Conclusion: PEM is associated with a significantly adverse outcome in patients with febrile neutropenia-- an almost double mortality rate and increased risk of complications like sepsis, increased LOS, and hospital costs. Neutropenic patients are markedly susceptible to fulminant systemic infections from various sources. PEM furthers this risk via weakening of host defenses including natural barriers and both innate and acquired immunity. Furthermore, in neutropenic patients with systemic infections, malnutrition may delay and impede wound healing along with immune responses which often contributes to a protracted course and adverse outcome. Nutrition in neutropenia has garnered limited attention, with some randomized trials showing limited to no benefit of the "neutropenic diet" in patients while depriving them of essential macro- and micronutrients. Nonetheless, current management guidelines for malnutrition in malignancies, particularly acute leukemias, are sparse. The profound impact of malnutrition in febrile neutropenia patients warrants further study, and we thus recommend further attention to screening practices and management strategies alongside primary treatment for malignancy and infection. Disclosures No relevant conflicts of interest to declare.

Survivorship in AML – a landmark analysis on the outcomes of acute myelogenous leukemia patients after maintaining complete remission for at least 3 years

Acute myeloid leukemia (AML) carries poor survival and high recurrence rate. We conducted a retrospective analysis of AML patients (N = 453) treated with chemotherapy only or chemotherapy + hematopoietic cell transplant (HCT) who maintained their first complete remission (CR) for ≥3 years. Prior comorbidities, new comorbidities, secondary malignancies, late relapse, and causes of death (COD) were documented. New comorbidities for chemotherapy only patients (n = 304) included renal disease (10%), and osteopenia/osteoporosis (38%) for HCT patients (n = 149). Incidence of hypertension was similar in the chemotherapy only cohort and chemotherapy + HCT cohort (14% vs 17%). Secondary malignancies occurred in 13%, commonly skin, prostate and breast cancers. Common COD included: secondary malignancy (4%), HCT complications (3%), and late relapses (5%). Overall, 12% had a late relapse. Median overall survival for chemotherapy only and HCT was 10.7 and 12.7 years, respectively. Long-term AML survivors need routine monitoring for comorbidities, secondary malignancies, and late relapses.

Combination of FLT3-ITD Allelic Ratio, NPM1 Mutation, and Immunophenotypic Markers to Modulate Outcome Prediction in Patients with Normal Karyotype Acute Myelogenous Leukemia Undergoing Hematopoietic Stem Cell Transplantation.

NPM1 mutation status and the allelic ratio (AR) of FLT3-internal tandem duplication (FLT3-ITD) are routinely tested for disease risk stratification in patients with normal karyotype (NK) acute myelogenous leukemia (AML); however, the predictive impact of immunophenotypic markers on different NPM1/FLT3 genotypes remains unclear. We performed a retrospective analysis of 423 patients with NK-AML subclassified into groups based onNPM1/FLT3 genotype. Allogeneic hematopoietic stem cell transplantation (HSCT) was performed in 124 of 423 patients (29%) and was significantly associated with longer event-free survival (EFS) and overall survival (OS), except for patients with the favorable genotype, defined as mutatedNPM1 (NPM1mut) combined with normal FLT3 status (FLT3-ITDneg) or FLT3-ITD AR <.5 (FLT3-ITDlow). A subset of AML patients bearing the favorable NPM1mut/FLT3-ITDneg/low genotype share similar outcomes with AML patients who have the intermediate FLT3/NPM1 genotype defined by normal NPM1 (NPM1wt) and FLT3-ITDneg/low. In these individuals, the lack of CD13 expression (CD13neg) was associated with shorter EFS (P=.041) and OS (P=.017). CD13neg was an independent predictor for shorter OS (hazard ratio, 1.985; P=.028).

Novel Approach for Bone Marrow Transplantation Conditioning in Acute Myelogenous Leukemia not Responding to the Induction Therapy Using Etoposide Carried in Lipid Core Nanoparticles: A Pilot Clinical Study

Allogeneic hematopoietic cell transplantation (HCT) is the treatment of choice for acute myelogenous leukemia (AML) not responding to induction therapy. It is a therapeutic choice for the blast phase of chronic myelogenous leukemia (CML-BP) in patients failing to respond to tyrosine kinase inhibitors (TKIs). Lipid core nanoparticles (LDEs) concentrate severalfold more in blast cells than in corresponding normal cells. Incorporation of anticancer drugs to LDE formulations increases the pharmacologic action and decreases the toxicity. We tested a drug-targeting system, LDE-etoposide plus total body irradiation (TBI; 1200 cGy dose), in 13 patients with AML not responding to the induction therapy and in 2 patients with CML-BP refractory to second-generation TKIs. The mean patient age was 46.7 years (range, 22 to 66 years). The LDE-etoposide dose was escalated at 20, 30, 40, 50, and 60 mg/kg. No patients developed grade 4 or 5 toxicity; however, mucositis grade 3 occurred in 6 patients, 3 patients experienced diarrhea, and 1 patient had an elevated total bilirubin level. No deaths were related to conditioning. All patients were successfully engrafted. The median times to neutrophil and platelet engraftment were 20 ± 5 days and 16 ± 4 days, respectively. Five patients (33.4%) had acute graft-versus-host-disease (GVHD), including 4 grade I, and 1 with grade II, and 8 patients (57.1%) had moderate-to-severe chronic GVHD. This pilot study shows the potential of LDE-etoposide plus TBI as an HCT conditioning regimen in AML patients not responding to the induction and refractory therapies for CML-BP patient. These findings pave the way for subsequent larger clinical trials.

Risk factors for and clinical outcomes of carbapenem non-susceptible gram negative bacilli bacteremia in patients with acute myelogenous leukemia

BackgroundCarbapenem is frequently used when gram negative bacilli (GNB) bacteremia is detected especially in neutropenic patients. Consequently, appropriate treatment could be delayed in GNB bacteremia cases involving organisms which are not susceptible to carbapenem (carba-NS), resulting in a poor clinical outcomes. Here, we explored risk factors for carba-NS GNB bacteremia and its clinical outcomes in patients with acute myelogenous leukemia (AML) that underwent chemotherapy.MethodsWe reviewed all GNB bacteremia cases that occurred during induction or consolidation chemotherapy, over a 15-year period, in a tertiary-care hospital.ResultsAmong 489 GNB bacteremia cases from 324 patients, 45 (9.2%) were carba-NS and 444 (90.8%) were carbapenem susceptible GNB. Independent risk factors for carba-NS GNB bacteremia were: carbapenem use at bacteremia onset (adjusted odds ratio [aOR]: 91.2; 95% confidence interval [95%CI]: 29.3–284.1; P < 0.001); isolation of carbapenem-resistant Acinetobacter baumannii (aOR: 19.4, 95%CI: 3.4–112.5; P = 0.001) in the prior year; and days from chemotherapy to GNB bacteremia (aOR: 1.1 per day, 95%CI: 1.1–1.2; P < 0.001). Carba-NS bacteremia was independently associated with in-hospital mortality (aOR: 6.6, 95%CI: 3.0–14.8; P < 0.001).ConslusionCarba-NS organisms should be considered for antibiotic selection in AML patients having these risk factors.

Quality of Life following Allogeneic Stem Cell Transplantation for Patients Age >60 Years with Acute Myelogenous Leukemia.

This study of patients with acute myelogenous leukemia (AML) age ≥60 years analyzed the association between patients' performance indices-Hematopoietic Stem Cell Transplantation Comorbidity Index (HCT-CI), Karnofsky Performance Score (KPS), and European Society for Blood and Marrow Transplantation (EBMT) risk score-before undergoing allogeneic hematopoietic stem cell transplantation (allo-HSCT) and quality of life (QoL), quantified using the Functional Assessment of Cancer Therapy-Bone Marrow Transplant Scale (FACT-BMT), in the first year after allo-HSCT. Over a period of 7 years, 48 evaluable patients underwent reduced-intensity conditioning allo-HSCT. The median patient age was 65 years (range, 60 to 74 years), with 2-year and 5-year overall survival (OS) of 65.8% and 52.3%, respectively. A significant improvement across all QoL scores was observed over the 12 months post-HSCT. An HCT-CI of 0 was associated with improved general QoL (FACT-G) score at 6 months compared with patients with an HCT-CI of 1 to 2 (P= .032). At 12 months post-HSCT, a pretransplantation HCT-CI ≥3 was correlated with lower QoL scores across the domains (symptom-related QoL [FACT-TOI], P= .036; FACT-G, P= .05; BMT-related QoL [FACT-BMT], P= .036). A pretransplantation KPS score of 100 versus 80 to 90 was predictive of improved QoL at 6 months post-HSCT (FACT-TOI, P=.009; FACT-G, P= .001; FACT-BMT, P= .002) but not at 1 year post-HSCT. We demonstrate that KPS and HCT-CI can predict QoL in the early post-transplantation period, with a favorable overall survival in a selected cohort of AML patients age ≥60 years.

Association of immunophenotype with expression of topoisomerase II \u03b1 and \u03b2 in adult acute myeloid leukemia

Anthracyclines used in the treatment of acute myelogenous leukemia (AML) inhibit the activity of the mammalian topoisomerase II (topo II) isoforms, topo II α and topo IIβ. In 230 patients with non-M3 AML who received frontline ara-C/daunorubicin we determined expression of topo IIα and topo IIβ by RT-PCR and its relationship to immunophenotype (IP) and outcomes. Treatment outcomes were analyzed by logistic or Cox regression. In 211 patients, available for analysis, topo IIα expression was significantly lower than topo IIβ (P < 0.0001). In contrast to topo IIα, topo IIβ was significantly associated with blast percentage in marrow or blood (P = 0.0001), CD7 (P = 0.01), CD14 (P < 0.0001) and CD54 (P < 0.0001). Event free survival was worse for CD56-negative compared to CD56-high (HR = 1.9, 95% CI [1.0–3.5], p = 0.04), and overall survival was worse for CD-15 low as compared to CD15-high (HR = 2.2, 95% CI [1.1–4.2], p = 0.02). Ingenuity pathway analysis indicated topo IIβ and immunophenotype markers in a network associated with cell-to-cell signaling, hematological system development/function and inflammatory response. Topo IIβ expression reflects disease biology of highly proliferative disease and distinct IP but does not appear to be an independent variable influencing outcome in adult AML patients treated with anthracycline-based therapy.

Improved Post remission survival of non- favorable risk Acute Myelogenous Leukemia (AML) patients following initial remission induction therapy with FLAG+/-Idarubicin versus 3 + 7 (Anthracycline + Cytarabine)

The fludarabine, high dose cytarabine and G-CSF with or without idarubicin combination regimen, referred to as FLAG+/-Ida, is commonly used as a salvage regimen for relapsed/refractory AML but its use as initial induction therapy has been more limited. The impact of choice of induction regimen on post remission survival remains unclear. We retrospectively analyzed 304 consecutive AML patients, with non-favorable NCCN risk who received initial treatment at our center with either 7 + 3 (n = 86) or FLAG+/-Ida (n = 218). Patients in the FLAG+/-Ida group were more likely to achieve remission after one course of induction (74 % vs 62 %, p < 0.001) and had a faster time to achieve CR (30 days vs 37.5, p < 0.001) compared to 7 + 3. The time from diagnosis to transplant was shorter among CR patients after FLAG+/-Ida compared to 7 + 3 (115 vs. 151 days, p < 0.003). The 3-year post-remission OS and DFS was significantly better for patients receiving FLAG-Ida at 54 % and 49 % compared to 39 % and 32 % for 7 + 3 respectively (P = 0.01). Factors associated with post-remission survival included age at CR1, NCCN risk, induction regimen (FLAG+/-Ida vs 3 + 7 h 0.62, p = 0.01) and receipt of HCT. Our data, with the limitations inherent to a retrospective analysis, shows that achieving CR after FLAG+/-Ida has better post remission survival than 7 + 3.

Outcomes of Acute Myelogenous Leukemia Patients Undergoing Haploidentical Hematopoietic Cell Transplantation with Post-Transplant Cyclophosphamide: Impact of Total Body Irradiation Versus Chemotherapy-Based Myeloablative Conditioning

<h3>Background</h3> Optimal myeloablative conditioning (MAC) in the setting of haploidentical hematopoietic cell transplantation (haplo-HCT) with post-transplant cyclophosphamide (PTCy) is unknown. We studied the outcomes of total body irradiation (TBI) vs. chemotherapy (CT) based MAC regimens in acute myelogenous leukemia (AML) pts undergoing haplo-HCT and reported to EBMT. <h3>Methods</h3> The study included 1008 AML pts who underwent haplo-HCT during 2010-2018, following TBI (n=89, 9%) or CT (n=919, 91%) based MAC. Regimen intensity was defined by EBMT criteria and the cases with busulfan dose <9 mg/kg or TBI dose ≤6 gray were excluded. Fludarabine-TBI (78%) and Thiotepa-busulfan-fludarabine (56%) were the most common MAC regimens in TBI and CT-cohorts, respectively. Pts in TBI cohort were more likely to be younger (median age, 38 vs. 47 yrs, p<0.01) and receive BM graft (57% vs. 43%, p-0.01) Other pt, disease and transplant characteristics were similar in both groups. Median follow up for TBI and CT cohort were 25.4 and 20.7 months, respectively. <h3>Results</h3> In univariate analysis, day 100 incidence of acute GVHD (aGVHD) II-IV and III-VI was 22% vs. 27% (p-0.44) and 12% vs. 12% (p-0.92) in TBI and CT cohorts, respectively. Two-yr total and severe chronic GVHD (cGVHD) incidence were 42% vs. 27% (p<0.01) and 9% vs. 12% (p-0.33) in TBI and CT cohorts, respectively. Graft failure was reported in 2 (2%) and 65 (7%)(p-0.08) pts who received TBI and CT-based MAC, respectively. Three (1%) pts died due to graft failure in CT-group. Death from veno-occlusive disease was reported in 1(3%) TBI pt and 11(3%) CT pts. Death due interstitial pneumonitis was reported in 1 (3%) TBI and 8(2%) CT pts. One pt died from a second malignancy in each group. In multivariate analysis, TBI was associated with higher incidence of overall cGVHD [HR=1.81, 95% CI:1.14-2.87, p-0.01] compared to CT. There was no difference in other outcomes such as extensive cGVHD[HR=0.34, p-0.07], relapse incidence(RI) [HR=1.32, p-0.22], nonrelapse mortality(NRM) [HR=0.82, p-0.52] and leukemia free survival(LFS) [HR=1.09, p-0.62], overall survival(OS) [HR=1.07, p-0.71] and GVHD free relapse free survival (GRFS) [HR=1.02, p-0.92]. 2-yr LFS and OS of TBI and CT cohort were 45% vs. 49%,p-0.98 and 50% vs. 55%,p-0.79, respectively (figure 1). Factors impacting OS were pt age (per 10yrs, HR=1.1, p-0.02), KPS≥90 (HR=0.55,p<0.01) and advanced disease status before haplo-HCT (HR=2.35, p<0.01). In a subgroup analysis of pts <40 yrs old and pts with pre-HCT disease status CR2 or advance disease, no interaction was observed between type of MAC and RI, NRM, LFS, OS and GRFS. <h3>Conclusions</h3> In this large relatively homogenous cohort of AML patients who received haplo-HCT with PTCy, TBI based MAC was associated with higher incidence of overall cGVHD without impacting other transplant outcomes compared to CT based MAC. A prospective study is needed to validate these findings.

Cytotoxic chemotherapy for AML in adults

Genomics and novel molecularly targeted drugs for treating acute myelogenous leukemia (AML) are developing rapidly. To optimize the allocation of patients to the best possible treatment, we have to expedite test results of cytogenetic and molecular analyses for target mutations such as CBF and FLT3, since gene mutations are specifically associated with patient prognosis and therefore inform medical decision making. However, novel agents cannot completely eradicate AML because of the emergence of resistance to these agents; therefore, at the moment it is still necessary to combine cytotoxic treatment with novel agents. Hence, it becomes vital to understand how to stratify AML patients and subsequently treat the right patients with the right combination of cytotoxic treatments and novel agents.

The impact of anti-thymocyte globulin on the outcomes of Patients with AML with or without measurable residual disease at the time of allogeneic hematopoietic cell transplantation.

Measurable residual disease (MRD) status pre-allogeneic hematopoietic cell transplantation (allo-HCT) has been shown to predict transplant outcomes. We investigated the effect of Anti-Thymocyte Globulin (ATG) on acute myelogenous leukemia (AML) relapse by pretransplant MRD status. AML patients undergoing allo-HCT in first complete remission from either a matched sibling or unrelated donor during the 2006-2017 period were selected. Outcomes of 1509 patients (MRD+, n = 426) were studied. ATG was used in 561 (52%) and 239 (58%) patients within the MRD- and MRD+ cohorts, respectively. In MRD- patients, ATG did not affect relapse incidence (RI) (HR = 0.80, p = 0.17), but was associated with reduced incidence of grade II-IV acute GVHD, grade II-IV and chronic GVHD, reduced nonrelapse mortality (HR = 0.66, p = 0.05), improved leukemia-free survival (HR = 0.74, p = 0.02), overall survival (HR = 0.69, p = 0.01), and GVHD-relapse free survival (HR = 0.62, p < 0.01). In MRD+ patients, ATG was associated with a lower incidence of chronic GVHD (total, HR 0.56 p = 0.03; extensive, HR 0.40 P = 0.01), without an impact on other allo-HCT outcome parameters, including RI(HR = 1.02, p = 0.92). The use of ATG was associated with reduced risk for GVHD. ATG did not increase RI, even in high-risk AML patients who were MRD+ before allo-HCT.

Outcomes of Total Body Irradiation- Versus Chemotherapy-Based Myeloablative Conditioning Regimen in Haploidentical Hematopoietic Cell Transplantation with Post-Transplant Cyclophosphamide for Acute Myelogenous Leukemia: ALWP of the EBMT Study

Background The use of haploidentical hematopoietic cell transplantation (haplo-HCT) with post-transplant cyclophosphamide (PTCy) is rapidly increasing. The safety and efficacy of myeloablative conditioning (MAC) in haplo-HCT has been reported in patients with acute leukemia. However, optimal MAC in haplo-HCT setting is unknown. We studied the outcomes of total body irradiation (TBI) vs. chemotherapy (CT) based MAC regimens in acute myelogenous leukemia (AML) patients undergoing haplo-HCT and reported to the Acute Leukemia Working Party of the EBMT. Methods The study included 1008 AML patients (secondary AML=149, 15%) who underwent haplo-HCT with PTCy during the years 2010-2018, following TBI (n=89, 9%) or CT (n=919, 91%) based MAC. Regimen intensity was defined by EBMT criteria and cases with busulfan dose &lt;9 mg/kg or TBI dose ≤6 gray were excluded. Baseline AML cytogenetic risk group was good, intermediate and poor in 8%, 65% and 27% of patients respectively. All pre-HCT disease status (CR1=434, 43%; CR2+=216, 21%; advanced=358, 36%) were included in the study. fludarabine- TBI (78%) and thiotepa- busulfan- fludarabine (56%) were the most common MAC regimens in TBI and CT-cohorts, respectively. Patients in the TBI cohort were more likely to be younger (median age, 38 vs. 47 yrs, p&lt;0.01) and receive BM graft (57% vs. 43%, p-0.01) Other patient, disease, and transplant related characteristics were similar in both groups. Median follow up for TBI and CT cohort were 25.4 (IQR-9.5-58.7) and 20.7 (IQR-11.7-40.3) respectively. Results In univariate analysis, day 100 incidence of acute GVHD (aGVHD) II-IV and III-VI was 22% vs. 27% (p-0.44) and 12% vs. 12% (p-0.92) in TBI and CT cohorts respectively. Two-year total and severe chronic GVHD (cGVHD) incidence was 42% vs. 27% (p&lt;0.01) and 9% vs. 12% (p-0.33) in TBI and CT cohorts respectively. More patients achieved neutrophil engraftment by day 30 in the TBI cohort (97% vs. 86%,p-0.05). Graft failure was reported in 2 (2%) and 65 (7%)(p-0.08) patients who received TBI and CT-based MAC respectively. There were 3 (1%) deaths related to graft failure in the CT-group. Death from veno-occlusive disease was reported in 1(3%) TBI pt and 11(3%) CT patients. The proportions of infection related deaths (TBI-29% vs. CT-32%) and GVHD related deaths (TBI-17% vs. CT-15%) were comparable. Death due to interstitial pneumonitis was reported in 1(3%) TBI and 8(2%) CT patients. Death from a second malignancy was reported in one pt in each group. In multivariate analysis, TBI was associated with a higher incidence of overall cGVHD [HR=1.81, 95% CI:1.14-2.87, p-0.01] compared to CT. There was no difference in other outcomes such as extensive cGVHD [HR=0.34, 95% CI:0.11-1.10, p-0.07], relapse incidence(RI) [HR=1.32, 95% CI:0.85-2.03, p-0.22], nonrelapse mortality(NRM) [HR=0.82, 95% CI:0.46-1.49, p-0.52] and leukemia free survival(LFS) [HR=1.09, 95% CI:0.77-1.55, p-0.62], overall survival(OS) [HR=1.07, 95% CI:0.74-1.56, p-0.71] and GVHD free relapse free survival (GRFS) [HR=1.02, 95% CI:0.74-1.40, p-0.92]. Two-year LFS and OS of TBI and CT cohorts were 45% vs. 49% (p-0.98) and 50% vs. 55% (p-0.79) respectively (Figure 1). Factors impacting OS were pt age (per 10yrs, HR=1.1, p-0.02), KPS ≥90 (HR=0.55, p&lt;0.01) and advanced disease status before haplo-HCT (HR=2.35, p&lt;0.01)(Table 1). Interestingly, cytogenetic risk groups had no impact on LFS or OS in this analysis. No interaction was observed between the type of MAC and RI, NRM, LFS, OS and GRFS in a separate subgroup univariate analysis of patients &lt;40 yrs old and patients with pre-HCT disease status CR2 or advance disease. Conclusions In this large cohort of AML patients who received first haplo-HCT with PTCy, TBI based MAC was associated with higher incidence of overall cGVHD without impacting other transplant outcomes compared to CT based MAC. In the absence of a prospective study, these findings may guide clinicians when choosing an optimal MAC in haplo-HCT with PTCy. Disclosures Dholaria: Celgene: Honoraria. Labopin:Jazz Pharmaceuticals: Honoraria. Angelucci:Jazz Pharmaceuticals: Other: Local advisory board; Roche: Other: Local advisory board; Novatis: Honoraria, Other: Chair Steering Committee TELESTO protocol; Celgene: Honoraria, Other: Participation in DMC; BlueBirdBio: Other: Local advisory board; Vertex Pharmaceuticals Incorp., and CRISPR Therapeutics: Other: Participation in DMC. Blaise:Jazz Pharmaceuticals: Honoraria; Molmed: Consultancy, Honoraria; Sanofi: Honoraria; Pierre Fabre medicaments: Honoraria. Mohty:Jazz Pharmaceuticals: Honoraria, Research Funding.

DNA Repair Genes' Expression Abnormalities in De Novo Acute Myelogenous Leukemia (AML): Implications for Targeted Treatment

INTRODUCTION AML is the most common malignant myeloid disorder in adults. Relapses are initiated by chemoresistant leukemic cells. DNA damage and repair mechanisms influence not only the genetic predisposition to leukemia but are also very important for refractoriness to treatment. The aim of this study was to investigate the possible alterations in the gene expression profile in DNA damage signaling pathways in two leukemic cell lines following their exposure to chemotherapeutic agents and verify the findings in AML patients. METHODS Kasumi-1 and MV4-11 AML cells were treated with either idarubicin (0.1μΜ) for 6h or cytarabine (1μΜ) for 48h. Dead cells were eliminated from drug-treated cells using the appropriate commercial kit. Gene expression profiling through PCR arrays analysis (RT2Profiler, Qiagen) was performed after RNA extraction from untreated, drug-treated and chemoresistant (live) cells following their exposure to cytotoxic agents. Human DNA Damage Signaling pathway related genes' expression was evaluated and analyzed through RT2Profiler PCR Array data analysis tool. Following our initial results, two genes were selected for further analysis: PPP1R15A and HUS-1 genes' relative expression was evaluated by qRT-PCR analysis with QuantiTect Primer Assays kit (Qiagen) using the 2^-∆∆Ct method. The analysis included 28 de novo AML patients before the onset of the 7+3 combination chemotherapy and 16 healthy donors. Eighteen cases had normal karyotype including 7 with flt3 mutation, 1 case had inv(16) and 9 cases intermediate risk karyotype. Statistics were performed through One Way Anova analysis. RESULTS PCR Array analysis after idarubicin and cytarabine treatment of Kasumi-1 cells revealed a significant up-regulation of genes involved in apoptosis, cell cycle, DNA damage and repair, and ATM/ATR signaling. Significant differences in their gene expression patterns were observed between cytarabine-treated Kasumi-1 cells and chemoresistant ones. HUS-1 gene (DSB) was 3x fold up-regulated in cytarabine-treated cells and 0.7x fold down-regulated in chemoresistant cells compared to untreated cells. Cytarabine and idarubicin treatment of MV4-11 cells led to an up-regulation of genes involved in cell cycle, DNA damage repair, including DSB repair and NER mechanisms. Most importantly, PPP1R15A gene's expression in both cytarabine and idarubicin chemoresistant MV4-11 cells was significantly 4.2x and 2.7x fold up-regulated compared to drug treated cells. Following these results the expression level of genes PPP1R15A and HUS1 was examined in the bone marrow cells of AML patients in order to verify their association with chemoresistance. PPP1R15A gene's relative expression was significantly up-regulated in non-responding to induction chemotherapy AML patients compared to responding (median: 2.705 vs. 0.73, p&lt;0.05) and in non-responding to chemotherapy AML patients compared to controls (median: 2.705 vs. 0.577, p&lt;0.01). HUS1 gene's relative expression was remarkably down-regulated in AML patients compared to controls (median: 1.585 vs. 7.74, p&lt;0.001). This was also observed comparing responding and refractory to chemotherapy AML patients to controls (median: 1.09 vs. 7.74, p&lt;0.001 and 1.585 vs. 7.74, p&lt;0.05, respectively). CONCLUSIONS The up-regulation of PPP1R15A gene in chemoresistant MV4-11 cells after treatment with cytotoxic agents is justified since this gene participates in growth arrest and apoptosis in response to DNA damage, negative growth signals and protein malfolding by binding to protein phosphatase PP1, and attenuating the translational elongation of key transcription factors through dephoshorylation of eukaryotic initiation factor 2a(eIF2a). Most importantly the significant increased baseline expression of PPP1R15A in AML chemoresistant patients indicates its involvement in chemoresistance mechanisms and paves the way for targeted treatment. HUS1 gene's expression was remarkably depressed in de novo AML samples. This gene is required for the optimal ATM/ATR signaling response to DSBs and replication stress forming part of the RAD9A-RAD1-HUS1 (9-1-1) complex functioning as a damage sensor in checkpoint pathway. Therefore the described above reduced expression in AML samples indicates reduced ATM-ATR response to DSBs associated with genetic instability and offers new options for synthetic lethality treatment strategies Disclosures Symeonidis: Tekeda: Membership on an entity's Board of Directors or advisory committees, Research Funding; Pfizer: Research Funding; Celgene: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Novartis: Membership on an entity's Board of Directors or advisory committees, Research Funding; MSD: Membership on an entity's Board of Directors or advisory committees, Research Funding; Janssen: Membership on an entity's Board of Directors or advisory committees, Research Funding; Gilead: Membership on an entity's Board of Directors or advisory committees, Research Funding; Sanofi: Research Funding; Roche: Membership on an entity's Board of Directors or advisory committees, Research Funding. Pappa:Roche: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Abbvie: Research Funding; Novartis: Honoraria, Research Funding, Speakers Bureau; Takeda: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Gilead: Honoraria, Research Funding; Janssen: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Amgen: Research Funding; Celgene / GenesisPharma: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding.

Acceleration of AML Progression By Cigarette Smoke Exposure or Condensate Exposure and Associated DNA Methylation Alterations

Subsets of acute myelogenous leukemia (AML) are characterized by molecular alterations with prognostic significance, however, little is known about how modifiable behaviors, such as cigarette smoking, intersect with genetic factors. Mutations rendering the Fms-like tyrosine kinase 3 (FLT3) constitutively active, such as internal tandem duplication (ITD), are associated with refractory disease and therapy resistance. Inhibition of the FLT3 kinase shows some benefit in this population, as highlighted by the FDA approvals of midostaurin and gilteritinib, but overall outcomes remain poor. Cigarette smoke exposure (CSE) also marks a population of patients with poor prognosis. Current and former smokers who develop AML are known to have worse survival as compared to never smokers (Alfayez M., et al. ASCO 2019), but the impact of FLT3 mutation and subsequent associated treatment response has not been studied. Also, the underlying mechanism of how history of cigarette smoking influences leukemia biology and response to therapy is poorly understood. In order to model a history of smoking in AML patients, NOD-SCID mice (n=25) were exposed to CSE using a smoking robot for 2 hours, 5 days/week, for 2 weeks. Mice were then inoculated via tail-vein injection with luciferase tagged human FLT3-ITD cells and leukemia burden was monitored through noninvasive imaging. CSE continued through the duration of the experiment, post engraftment. Control "non-smoking" mice (n=15) were only injected with leukemia cells. Within one week post leukemic introduction, a significant increase in leukemic burden as measured by bioluminescence was apparent in mice exposed to CSE versus control mice (P-value&lt;0.0001). To model the impact of smoking cessation upon diagnosis of AML in patients, experiments were modified to halt CSE once leukemic engraftment was detectable by non-invasive imaging. Smoking cessation versus continuous smoke exposure yielded reduced relative leukemic burden. Mice with continuous smoke exposure had higher rates of leukemia compared to mice who ceased smoking (n=10) one week prior (P-value =0.0064). These rapid changes in leukemic burden suggest that CSE may prime the microenvironment to promote leukemia progression or directly affect leukemia cells. To address the latter possibility, human AML cells were exposed to cigarette smoke condensate (CSC), which contains the chemicals present in cigarettes, for two weeks before introducing the cells into mice. A significant increase in leukemic burden was observed in mice injected cells exposed to CSC compared to mice injected with unexposed leukemia cells (P-value &lt;0.001), highlighting a direct role for the chemicals in cigarettes on in vivo leukemia proliferative factors. Smokers are known to carry altered global DNA methylation signatures that persist decades after quitting. To measure DNA methylation changes in the in vivo models described above, we examined spleens of non-smoking and smoke exposed mice by reduced representative bisulfite sequencing (RRBS). Sequences were mapped to either the human or mouse genome, (enabling identification of leukemia specific versus microenvironment specific alterations) and were compared in the smoking and non-smoking mice. Over 200 genes exhibited significant DNA methylation alterations in their promoter regions. Genes involved in RNA polymerase activity and chromatin remodeling were highly represented amongst those with altered DNA methylation. The clinical significance of our observations was confirmed in a cohort of 58 treatment naïve FLT3-ITD AML patients at MD Anderson receiving intensive induction therapy: 41 never smokers and 17 ever smokers. Smokers had significantly reduced survival as compared to the never smokers (median overall survival of 18 vs 23 months, P-value 0.0092). Collectively our findings indicate that short-term CSE is sufficient to alter DNA methylation patterns and accelerate the early progression of FLT3-ITD AML in vivo. Smoking cessation upon diagnosis may slow leukemic growth relative to smoking throughout AML therapy prompting the consideration of behavioral interventions for smokers with AML. Improved understanding of the mechanism of leukemic progression and drug resistance from CSE is expected to lead to improved treatment paradigms designed for patients with a history of cigarette smoking. Disclosures Konopleva: Genentech: Honoraria, Research Funding; Kisoji: Consultancy, Honoraria; F. Hoffman La-Roche: Consultancy, Honoraria, Research Funding; Ascentage: Research Funding; Reata Pharmaceuticals: Equity Ownership, Patents &amp; Royalties; Ablynx: Research Funding; Cellectis: Research Funding; Amgen: Consultancy, Honoraria; Calithera: Research Funding; Stemline Therapeutics: Consultancy, Honoraria, Research Funding; Forty-Seven: Consultancy, Honoraria; Eli Lilly: Research Funding; AbbVie: Consultancy, Honoraria, Research Funding; Astra Zeneca: Research Funding; Agios: Research Funding. Jabbour:Cyclacel LTD: Research Funding; Pfizer: Consultancy, Research Funding; Amgen: Consultancy, Research Funding; Adaptive: Consultancy, Research Funding; Takeda: Consultancy, Research Funding; BMS: Consultancy, Research Funding; AbbVie: Consultancy, Research Funding. DiNardo:agios: Consultancy, Honoraria; abbvie: Consultancy, Honoraria; jazz: Honoraria; medimmune: Honoraria; notable labs: Membership on an entity's Board of Directors or advisory committees; daiichi sankyo: Honoraria; syros: Honoraria; celgene: Consultancy, Honoraria.

Deep DNA Sequencing Identifies Small Mutations in Patients with Acute Myelogenous Leukemia (AML) and High-Risk Myelodysplastic Syndromes (MDS): Analysis of Intratumor Genomic Heterogeneity for Prediction of Disease Relapse

Background: Patients with unfavorable AML have an estimated 3-year overall survival (OS) of &amp;lt; 15% with standard chemotherapy treatment. The recommendation for consolidative allogeneic transplant can be challenging and is usually an individualized assessment. Accurate and sensitive genomic data may improve the decision making process. Detailed mutational analyses using myeloid-specific gene assays have shown to refine disease prognostication from standard six-gene mutational analysis (Gerstung et al. Nature Genetics2017, Dohner et al. Blood2017). Several studies using mutation analysis for assessing minimal residual disease (MRD) have been performed. Specifically, in two large studies, isolated presence of DNMT3A, TET2, or ASXL1mutations (associated with clonal hematopoiesis) was not prognostic but detection of other mutations, independent of pathogenicity, at &amp;gt;2.5% predicted relapse, relapse-free survival, and overall survival (Jongen-Lavrencic et al. JEJM2018, Morita et al. JCO2018). Of note, flow cytometry was also used to detect minimal residual disease (MRD), and at a sensitivity of 0.1% provided independent prognostic value; however even when used in combination, nearly 25% of relapses were not predicted. At Rutgers, we utilize deep DNA sequencing and real-time multiplex PCR assays to detect mutant alleles in the presence of 10,000 wild-type fragments. Here, we hypothesize that detailed analysis of available mutational data and detection of mutations at allele frequencies &amp;lt;2.5% in pre-treatment and sequentially collected samples during treatment serves as a targeted and ultrasensitive measure of clonal heterogeneity and may correspond better to prognosis and ultimately guide further treatment decisions based on MRD sequencing. Methods: We recruited 99 patients with newly diagnosed high-risk MDS and/or AML.Each patient had standard myeloid mutation profiles obtained at diagnosis (pre-treatment) and on the 'day 30' recovery bone marrow. Patient characteristics and bone marrow biopsy results were obtained including standard cytogenetics and conventional molecular studies. Additional and contemporaneous analyses were performed for 18 patients, diagnosed and treated from February 2017 through July 2019,utilizinga 49-gene panel (RainDance Technologies) on Illumina MiSeq at high depth (2,000x-20,000x). We identified all sites different from the reference using an inclusive variant caller and used a Bayesian approach to detect true mutations against mutation-specific background error at &amp;gt;0.1% allele frequencies. We tested the variants against previously sequenced non-malignant samples and guided the analysis by detected mutations in longitudinal data (Hadigol et al. BMC Bioinformatics2018, Rabadan et al. J Stat Phys2018). Results:The median age of patients with deep-sequencing data was 55 years (range, 26-73 [n=4 male; n=14 female]). There were 14 patients with AML and 4 patients with high-risk MDS. Sixty-one percent of patients received standard 7+3 induction therapy and 14 patients received consolidative allogeneic stem cell transplant (SCT), 93% of whom received it at first complete remission (CR1). With the median follow-up of 19 months (range, 12-27), the median time to relapse in 5 patients (28%) was 13 months (range, 8-15). In the relapsed patients, there was a median of 1 mutation (range, 0-2) reported by conventional variant calling methods at CR1. However, Bayesian deep-sequencing analysis identified additional non-synonymous coding mutations (range, 1-4) at allele frequencies &amp;lt;2.5% in 4 of these patients for whom sequencing data was available at this time point (Table). It is important to highlight that some of these mutations were not detected at initial diagnostic sample and could be present in clones with higher fitness after treatment. Conclusion: Our approach identified new and relevant mutations that were not reported with conventional genomic analysis at a crucial time point in the measurement of treatment response in AML and high-risk MDS. Data such as these may refine prognostication and ultimately be used as to help guide further treatment decision making for patients. Continued and larger prospective analyses with novel deep-sequencing technology are needed to better inform outcomes for AML and high-risk MDS patients. Disclosures No relevant conflicts of interest to declare.