Bone Marrow Blast Percentage Research Articles

Relation between FMS-like tyrosine kinase 3 factor and hematological parameter in acute lymphoblastic leukemia patients by flow cytometry

BACKGROUND: Acute lymphoblastic leukemia (ALL) is a heterogeneous disorder that is caused by the clonal expansion of immature lymphoid cells with a high rate among children more than adults. FMS-like tyrosine kinase 3 (FLT3) is a cellular receptor belongs to the Class III receptor tyrosine kinase family. The main expression of FLT3 on bone marrow (BM) cells especially CD34+ hematopoietic stem cells, early progenitor cells, dendritic progenitor cells, and other cells of organs (brain, placenta, and testis). Activation of FLT3 results in increased cell proliferation, decreased cell apoptosis, and inhibition of differentiation of cells. This study aims to detect the expression of the FLT3 cluster of differentiation antigen 135 (CD135) in childhood B-ALL patients. Moreover, to correlate this expression with hematological parameters include a complete blood count and BM examination findings and clinical parameters. PATIENTS, MATERIALS AND METHODS: This study was conducted on 30 newly diagnosed pediatric ALL patients. Diagnosis of the disease was based on the blood film, BM examination findings, cytochemistry, and flowcytometry of peripheral blood (PB) and/or BM sample, 1 ml of PB and/or BM sample was collected in EDTA tubes for flowcytometry for detection of CD135. RESULTS: This study found that male patients were more than females with a male-to-female ratio (1.14:1) and a median age of 5 years. Most of the patients had a positive expression of the FLT3 receptor and according to NCI risk groups, 60% of patients fall in the standard risk and 40% in the high-risk group. There was a significant correlation between the level of FLT3 (CD135) and age but no significant correlation with hemoglobin, white blood count, platelets, and peripheral or BM blast percentage. CONCLUSION: In this study, the patients with positive FLT3 blast cells (which is a bad prognostic factor) were associated with good prognostic factors. This proves that FLT3 is an independent prognostic factor.

Prognostički faktori rizika za ranu smrt kod bolesnika sa akutnom mijeloidnom leukemijom

Introduction: Early death is a known complication in the treatment of patients suffering from acute myeloid leukemia (AML). It has been defined as death occurring within 28 days of the initiation of induction chemotherapy. Aim: Determining the clinical characteristics of the patient, the risk factors, the frequency, and the most common causes of early death in AML patients. Materials and methods: This retrospective study included 248 patients with diagnosed AML. At diagnosis, the following demographic and clinical-laboratory characteristics were recorded: sex, age, general functional status, i.e., performance status according to the ECOG scale, complete blood count, LDH level in the blood, percentage of blasts in peripheral blood and bone marrow, fibrinogen, PT, aPTT, D-dimer, and BMI. Patients were treated with induction and reduction chemotherapy and palliative therapy. Statistical analysis was performed using the data from the discharge summaries taken from the registers of the Clinic for Hematology of the Clinical Center of Serbia. Results: Early death occurred in 53 (21.4%) patients. The prognostic risk factors for early death were the following: age (p = 0.047), ECOG ≥ 2 (p = 0.001), leukocyte count ≥ 30 x 109 /l (p = 0.022), LDH level ≥ 450 U/l (p = 0.022), the percentage of blasts in peripheral blood (p = 0.005) and the percentage of blasts in bone marrow (p = 0.003), PT (p < 0.001), as well as the ISTH score (p = 0.018). The most common cause of early death in patients aged 40 - 65 years was sepsis, while in patients older than 65 years it was respiratory failure. Conclusion: The study showed that age, the leukocyte count, the percentage of peripheral blood and bone marrow blasts, the ECOG score, LDH, PT, and the ISTH score were significant prognostic risk factors of early death in patients with AML, and that the most common cause of early death in patients aged 40 - 65 years was sepsis, while in patients older than 65 years it was respiratory failure.

Prognostic value of renin gene expression in acute myeloid leukemia

Aims To evaluate the renin gene (RG) expression pattern in newly diagnosed patients with acute myeloid leukemia (AML), aiming to figure out its prognostic value in correlation with clinical characteristics and outcomes of the chemotherapy course. Settings and design This study was clinical trial performed in the National Cancer Institute (NCI), Cairo University. Patients and methods We investigated the expression of the RG in 90 patients with AML using real-time PCR. Levels of RG were correlated with the different patients’ characteristics and outcomes of chemotherapy. Statistical analysis used χ 2 test and Student t test were used to compare between RG positive and negative groups. SPSS software was used to perform the statistical analysis. Results RG presented in 90 (72%) patients with AML. Both renin positive and negative populations showed no statistically significant difference, regarding all clinical parameters evaluated and the prognostic outcomes. Positive gene patients were associated with nonsignificantly lower percentages of bone marrow and peripheral blood blasts (P=0.534 and 0.074, respectively). In addition, they showed nonsignificant difference regarding the incidence of all types of cytogenetics (P=0.467) and the same results for Flt3 gene expression (P=0.751). Moreover, they showed nonsignificant difference regarding complete response rates, relapse rates, and survival rates (P=0.473, 0.636, and 0.152, respectively). Conclusion RG expression has no significant role in determining the prognosis of patients with AML. This includes different prognostic outcomes, including response to treatment, survival rates, relapses, and disease-free periods.

FLT3 Gene Mutation in Acute Myeloid Leukemia: Correlation with Hematological, Immunophenotypic, and Cytogenetic Characteristics

Introduction In acute myeloid leukemia (AML), FMS-like tyrosine kinase 3-internal tandem duplication (FLT3-ITD) is a common driver mutation associated with high tumor burden and poor prognosis. This mutation is common in normal karyotype AML and such patients have high leukocyte count. The presence of this mutation can be predicted by certain hematological and immunophenotypic characteristics in day-to-day practice. Objective This study was undertaken to assess the strength of association between FLT3 gene mutation and hematological and immunophenotypic characteristics. Materials and Methods Morphological, hematological, immunophenotypic, and cytogenetic characteristics of FLT3 mutations recorded in 424 patients of AML in adults and children between 2016 and 2019 in a tertiary care cancer center in Western India. Blasts were classified according to French-American-British method. Tumor burden was assessed by serum lactate dehydrogenase (LDH) levels, leucocyte count, and peripheral smear blast percentage. Results Out of 424 cases, FLT3-ITD and FLT3-tyrosine kinase domain mutation were found in 72 and 25 AML patients, respectively. Patients with FLT3 mutation had high tumor burden, characterized by high leukocyte count (p < 0.001), peripheral blood (p = 0.01) and bone marrow (p = 0.03) blast percentage, and high serum LDH (mean 777.8 vs. 586; p = 0.10) compared with FLT3-negative patients. They also featured high platelet count (p < 0.001). Morphological, immunophenotypic, and cytogenetic characteristics also have been presented in the study. Conclusion Observations of the study suggest the presence of definitive hematological and immunophenotypic characteristics along with raised serum LDH levels serve as surrogate markers and indicators of FLT3 mutation in AML patients.

Using Circ-ANAPC7 as a Novel Type of Biomarker in the Monitoring of Acute Myeloid Leukemia

Introduction: Circular RNAs (circRNAs) are a novel class of RNAs which occupy gene expression at the transcriptional or post-transcriptional level, involve in many physiological processes, and participate in many diseases, especially in cancer. Our previous study showed 1 altered circRNA named circ-anaphase promoting complex subunit 7 (ANAPC7) that was upregulated in acute myeloid leukemia (AML). To further clear the expression and clinical significance of circ-ANAPC7, we enlarged the sample size and illuminated the diagnostic and monitoring value of circ-ANAPC7 in AML. Methods: Real-time quantitative reverse transcription-polymerase chain reaction (RT-qPCR) was supposed to confirm the expression of circ-ANAPC7 of AML patients. We assessed the correlation of circ-ANAPC7 and clinical variables using the Spearman correlation test. The receiver operating characteristic (ROC) curve was carried out to evaluate the diagnostic value. Results: Circ-ANAPC7 was first found to be upregulated in AML, and its expression was correlated to white blood cell counts in peripheral blood and blast percentage in bone marrow. ROC curve analysis revealed that circ-ANAPC7 has a significant value of auxiliary AML diagnosis (area under the curve = 0.915, p < 0.001). Furthermore, the expression level of circ-ANAPC7 was changed accompanied with disease condition transformation. Conclusion: Circ-ANAPC7 was upregulated in newly diagnosed and relapsed AML. It may serve as potential biomarkers for AML patient’s diagnosis and monitoring.

Itga7 Relates to Disease Risk, Pathological Feature, Treatment Response and Survival in Ph – Acute Lymphoblastic Leukemia

Background: This study aimed to investigate clinical involvement of ITGA7 in Philadelphia-chromosome-negative acute lymphoblastic leukemia (Ph-ALL). Methods: We sampled bone marrow (BM) from 91Ph- ALL patients and 20 healthy donors (HDs), detecting ITGA7 expression in BM. Results: ITGA7 was highly expressed in Ph- ALL patients at differentiating values between Ph- ALL patients and HDs. Elevated ITGA7 expression was associated with CNS leukemia (CNSL) occurrence and increased percentage of BM blasts in Ph- ALL patients. Elevated ITGA7 expression was linked with lower complete remission rate (CR), worse event-free survival, and worseoverall survival in Ph- ALL patients. Conclusion: ITGA7 highly expressed, correlated with CNSL occurrence and higher BM blasts, furthermore predicts lower CR rate and worse prognosis.

Long-Term Subgroup Analyses from Azacitidine Vs. Decitabine in Unfit Newly Diagnosed Acute Myeloid Leukemia Patients: Results from the Pethema Registry

Long-Term Subgroup Analyses from Azacitidine Vs. Decitabine in Unfit Newly Diagnosed Acute Myeloid Leukemia Patients: Results from the Pethema Registry

Prediction of Early Mortality with Non-Intensive Acute Myeloid Leukemia (AML) Therapies: Analysis of 1336 Patients from MRC/NCRI and SWOG

Prediction of Early Mortality with Non-Intensive Acute Myeloid Leukemia (AML) Therapies: Analysis of 1336 Patients from MRC/NCRI and SWOG

Clinical Outcomes of Adults and Young Adults (AYA) with Acute Lymphoblastic Leukemia (ALL): A Multicenter Analysis of Pediatric-Inspired Protocol (MASPORE) Vs Hyper-CVAD in Singapore

Introduction:In acute lymphoblastic leukemia (ALL) adolescents and young adults (AYA), there are benefits when using pediatric over adult treatment regimes. There is improved overall survival (OS), progression free survival (PFS) and reduced need for hematopoietic stem cell transplantation; all while having an acceptable toxicity profile. Yet, studies supporting this were largely performed in a western population (e.g., United Kingdom and United States) and thus may have had limited representation of the Asian population. Whether these results are generalizable and applicable to an Asian population is in question. MASPORE, a locally designed pediatric regiment based on BFM regimen, which has been used successfully in Singapore and Malaysia's AYA cohort since 2007. MASPORE protocol utilized PCR-based minimal residual disease (MRD) marker to risk stratify patients according to disease severity and used a 3- or 4-drug induction regimen depending on intermediate or high-risk stratification (L-asparaginase, Vincristine, Dexamethasone +/- daunorubicin). In contrast HyperCVAD does not use MRD to stratify or guide management. In this retrospective study performed in Singapore, we aim to demonstrate that MASPORE is an effective treatment option for AYA ALL in Asian population.Methods:Patient registries (IRB approved) spanning from January 2005 to June 2021 from three tertiary hospitals in Singapore were reviewed. ALL patients who were AYA, defined as less than 40 years of age, treated during this time were included and analyzed. Patients were treated with either the pediatric protocol MASPORE or with the adult protocol HyperCVAD. Patients who are Philadelphia positive were excluded from the MASPORE arm up to 2020. Patients' demographics, functional status, risk profile, adverse events, as well as the hematological response and transplant status were collected and analyzed with Pearson chi-square test. Kaplan Meier curve analysis were performed for OS and PFS with SPSS software.Results:In this retrospective study, 116 patients were analyzed. Among these patients 29 (25%) received MASPORE and 87 (75%) received HyperCVAD. The median age was 23 (range 18-40) for MASPORE arm vs 28 years (range 15-40) for the HCVAD arm. median follow-up time was 4.5 vs 10.8 years. Both groups were similar in gender, race, ECOG status, and ALL risk status at diagnosis. Likewise, both arms did not have differences in starting hematological parameters: hemoglobin, total white blood cell count, platelet count, absolute neutrophil count, and bone marrow blast percentages. Median time from diagnosis to treatment was 3 and 4 days for MASPORE and HyperCVAD arms respectively. There were increased adverse rates for patients in the MASPORE arm. They had more (13.8 vs 0.0%, p < 0.001) of which 75% of the pancreatitis were CTCAE grade 3/4, avascular necrosis (13.8 vs 2.2%, p = 0.016), cerebral venous thrombosis (13.8 vs 1.1%, p = 0.004) and other thrombosis (27.6 vs 5.7%, p = 0.004). For the MASPORE and HyperCVAD arms there was one induction death, one from sepsis and the other from pneumonia . Both arms managed to achieve complete response (CR) with equivalent rates (82.5 vs 80.5%, p = 0.752). However, there was less relapsed or refractory disease in those treated with MASPORE (10.3 vs 44.8%, p < 0.001). The 5- OS was better in the MASPORE versus the HyperCVAD arm (4.4 vs 3.7 years; p = 0.049). Likewise, the 5-year PFS was superior in the MASPORE arm (4.2 vs 3.2 years, p = 0.034). Furthermore, a smaller proportion of patients required consolidative stem cell transplant (13.8 vs 49.4%, p < 0.001).Conclusion:The pediatric-inspired protocol MASPORE achieved similar CR rates with OS and PFS benefit, reduced relapse rates, and less need for consolidative stem cell transplant. MASPORE serves as a viable treatment option when treating AYA patients with ALL. Larger prospective studies are needed to further explore its use. [Display omitted] DisclosuresNo relevant conflicts of interest to declare.

High Effectiveness and Safety of Anti-CD7 CAR T-Cell Therapy in Treating Relapsed or Refractory (R/R) T-Cell Acute Lymphoblastic Leukemia (T-ALL)

BackgroundCompared with the substantial efficacy of chimeric antigen receptor T-cell (CAR-T) therapy that has achieved in B-ALL, whether CAR-T therapy is effective and safe for patients with T-ALL is still being explored in early stage clinical trials. Here, we present outcomes from our phase 1 clinical trial of CD7-targeting CAR-T (CD7CAR) cells therapy for R/R T-ALL (NCT04572308).MethodsPeripheral blood (PB) mononuclear cells were obtained by leukapheresis. T cells were separated and transduced with lentivirus. The second-generation CD7CAR is composed of an anti-CD7 single-chain antibody, a IgG4 hinge region, a CD28TM transmembrane domain, an intracellular co-stimulatory domain of 4-1BB and CD3ζ, and the truncated EGFR protein linked by T2A. All patients received intravenous fludarabine (30 mg/m 2/d) and cyclophosphamide (300 mg/m 2/d) for 3 days prior to CD7CAR infusion.ResultsSeventeen R/R T-ALL patients were enrolled between December 2020 and June 2021. Characteristics of patients are shown in Table 1. Data from 14 patients with a median age of 17 years (range: 3-42 years) were available for evaluation. The rest 3 patients were withdrawn from study within 14 days due to rapid disease progression. High-risk subtype patients enrolled including 1 with Ph-positive T-ALL and 3 with early T-cell precursor (ETP)-ALL. Seven of the 14 patients also had high-risk genotypes, namely SIL-TAL1, EZH2, TP53, RUNX1, BCR-ABL, JAK1 and JAK3. At enrollment, the median percentage of bone marrow (BM) blasts was 11.53% (range: 0.18%-65.03%), and 5 of 14 patients had extramedullary involvements, including optic nerve involvement (N=2), central nervous system leukemia (N=3), diffuse extramedullary involvements (N=2), and bulky lymph nodes in the neck (N=1). Patients were heavily pretreated with a median of 5 prior lines of therapies (range: 3-8 lines) and three relapsed from prior allogeneic hematopoietic stem cell transplantation (allo-HSCT).CD7CAR-T cells were 100% successfully manufactured with a transfection efficiency of 93.8% (range: 59.6%-99.9%). Twelve of 14 participants received bridging chemotherapy. A single dose of CD7CAR-T cells was infused to patients, with 2 receiving a low-dose (0.5x10 5 cells/kg), 11 receiving a medium dose (1-1.5x10 6 cells/kg) and 1 receiving a high-dose (2x10 6 cells/kg).By the data cutoff date (July 12, 2021), the median follow-up time was 105 days (range: 32-206 days, Fig.1A). By day 28 post infusion, 92.9% (13/14) of patients achieved complete remission (CR, N=4) or CR with incomplete hematological recovery (CRi, N=9) in their BM, with all 13 patients achieving minimal residual disease (MRD) negative CR/CRi. Additionally, 4/5 patients with extramedullary involvement also achieved extramedullary remission at a median of day 32 (range: 28-90 days) post infusion. Consolidation allo-HSCT was permitted at the treatment physician's discretion and the patient's preference. A total of 11/14 patients were bridged to consolidation allo-HSCT at a median of 57 days post CD7CAR infusion, of which 9 patients have remained MRD-negative CR/CRi. One patient who had allo-HSCT prior to CD7CAR infusion died following a second haplo-HSCT due to acute graft-versus-host disease. Of the other 3 patients who were not bridged to allo-HSCT, 1 patient relapsed on day 28 due to rapid disease progression after initial CRi on day 14. Thirteen of 14 patients experienced mild CRS (Grade ≤2). One patient had Grade 3 CRS. The median time to onset of CRS was 1 day (range: 0-11 days), with a median duration of 14 days (range: 3-25 days). Neurotoxicity (Grade 1) occurred in only 1 patient.After infusion, the median peak of CAR-T copy number was 2.38 ×10 5copies/µg DNA (range: 0.2-6.67 ×10 5 copies/µg DNA), which occurred on day 20 (range: 10-42 days, Fig.1B). Importantly, CD7CAR persisted well in PB at a median of 52.5 days (range:20-120 days) at last evaluation regardless of transplantation status. Maximum proportion of CD7CAR-T cells proliferation reached 84.95% by flow cytometry (Fig.1C).ConclusionsOur results demonstrate that CD7CAR therapy is safe and highly effective in treating patients with heavily pretreated R/R T-ALL, including those with extramedullary involvements, a history of prior allo-HSCT or with high-risk subtypes. More patients and a longer observation time are needed to further evaluate the potential beneficial advantages and side effects of CD7CAR therapy for T-ALL patients. [Display omitted] DisclosuresNo relevant conflicts of interest to declare.

First-in-Human Clinical Study of a Novel CD7-Targeted Chimeric Antigen Receptor (CAR)-T Cell Therapy for Refractory/Relapsed Mixed Phenotype Acute Leukemia (MPAL)

IntroductionMixed phenotype acute leukemia (MPAL) is a rare subtype of acute leukemia with features of both acute lymphoblastic leukemia (ALL) and acute myeloid leukemia (AML). The blast cells of MPAL express multilineage immunophenotypic markers and may have a shared B/T/myeloid phenotype. CD7 is expressed by the leukemic blasts and malignant progenitor cells of approximately 30% of AML patients. MPAL is usually associated with a relatively poor prognosis which is even worse compared to either AML or ALL, and even among patients that undergo allogeneic hematopoietic stem cell transplantation (allo-HSCT), underscoring the need for new therapies for these patients. CAR-T cell therapy has shown to be efficacious with a tolerable safety profile in a subset of hematological malignancies. Here, we explored the safety and efficacy of CAR-T therapy in treating refractory/relapsed (r/r) MPAL patients with CD7-positive in a phase I dose-escalation clinical study (https://clinicaltrials.gov NCT04938115).MethodsPeripheral blood (PB) mononuclear cells were obtained from patient themselves or patient transplant donors for those who relapsed post-transplant by leukapheresis. T-cells were purified using CD3+ magnetic beads or CD4+ and CD8+ magnetic beads. The second-generation CD7 CAR with a 4-1BB costimulatory domain was manufactured per the manufacturer's protocol. This phase I dose escalation study was initiated to explore the safety and efficacy of CD7 CAR-T in treating patients with MPAL. Prior to the CAR-T cells infusion, patients received systemic bridging chemotherapy due to rapid disease progression and then all patients received intravenous fludarabine (30mg/m 2/d) and cyclophosphamide (300mg/m 2/d) (FC) lymphodepleting chemotherapy for 3 consecutive days (Day -5 to Day -3). The median time from leukapheresis to CAR-T cell infusion was 14 days.ResultsFrom Nov. 2020 to June 2021, 5 adult acute leukemia patients with CD7-positive (4 MPAL, 1 FLT3-mutated AML) were enrolled and infused with CD7 CAR T-cells, one with a low-dose (1.5×10 5/kg), 2 with a medium dose (5.0×10 5/kg), and 3 with a high dose infusion (1.0×10 6/kg). The median transduction efficiency of products was 70.4% (range: 32.0%-96.9%). As of July 30, 2021 cut-off date, the median observation time was 37 days (range: 35-232 days). Characteristics of enrolled patients are shown in Table 1. The median age was 33 years (range: 21-37 years), and the median bone marrow (BM) blasts percentage by morphology was 28.0% (range: 2.5-51.5%) at enrollment. Four patients had prior allo-HSCT history including one who had extramedullary disease (EMD) who relapsed following a 2 nd transplant and had also received CD19 CAR-T cell therapy prior to enrollment in the current trial. The median interval period from prior transplant to CD7 CAR-T cell infusion was 16 months (range: 8-23 months). Following infusion, the median peak of circulating CD7 CAR-T cell was 1.17×10 5copies/μg (0.651~7.04×10 5copies/μg) genomic DNA which occurred around Day 21 (Day14 - Day21) and 59.2% (4.28%~74.58%) occurring on Day18 (Day11-Day21) by q-PCR and flow cytometry respectively (Fig.1).Four weeks post CD7 CAR-T cell infusion, 4/5 patients achieved complete remission (CR) or CR with incomplete blood recovery (CRi) in BM and all achieved minimal residual disease (MRD)-negative CR. One patient who relapsed post 2 nd transplant, also with EMD, achieved CR in BM, however, remission was not achieved in EMD through PET-CT evaluation on Day 35.One MRD-negative CR patient subsequently underwent consolidative allo-HSCT 120 days post CD7 CAR T-cell infusion and has remained in MRD-negative CR. Other 3 patients without consolidative allo-HSCT remained in MRD-negative CR till the last follow-up. All 5 patients developed cytokine release syndrome (CRS)-three of 5 patients had grade I CRS, one patient had grade II and one patient had grade III CRS. None of the patients had neurotoxicity. Among the 4 patients who had prior allo-HSCT, 1 developed grade I graft-versus-host disease post CAR-T therapy.ConclusionThis study demonstrated that CD7-targeted CAR-T therapy offers an opportunity to achieve CR for CD7-positive MPAL patients even for those who relapsed post-transplant. Safety was manageable, however, more data on additional patients and longer observation times are needed to further evaluate the efficacy of CD7 CAR-T products. [Display omitted] DisclosuresBa: SenlangBio: Current Employment.

Clinical Characteristics Associated with Venous Thromboembolism in Patients with Non-APL Acute Myeloid Leukemia

INTRODUCTIONVenous thromboembolism (VTE) is an important complication of many cancers. Although more widely recognized in solid tumors, VTE is still an appreciable cause of morbidity and mortality among patients with hematologic malignancies. For example, acute promyelocytic leukemia (APL) is a well-recognized risk factor for disseminated intravascular coagulation (DIC), which can lead to thrombosis. Patients with non-APL AML are also at increased risk for VTE, though the exact mechanisms are currently unclear. Thus, we sought to explore how patient demographics, comorbidities, hematologic factors, coagulation parameters, and cytogenetic and molecular profiles impact the incidence of VTE in patients with non-APL AML. METHODSThis was a retrospective observational case-control study of 120 non-APL AML patients treated at the University of Wisconsin-Madison. The electronic health record was manually reviewed for extraction of the relevant clinical information. Coagulation parameters assessed included INR, PTT, fibrinogen, D-dimer, and fibrin monomer. Coagulation data were collected both at diagnosis and during the first 7 days of induction, if applicable. Cytogenetics was categorized based on the presence of a normal karyotype or not. Genomic data were subdivided into eight different functional categories of genes that are commonly mutated in AML. Other factors that could potentially increase the risk of thrombosis were also analyzed, including age, sex, BMI, baseline blood counts, baseline bone marrow blast percentage, previous history of VTE, use of antifibrinolytic agents, and whether blood products were transfused during the early treatment period. The variables of interest between VTE cases and non-VTE cases were compared using the nonparametric Wilcoxon rank sum test. RESULTSAcross the entire cohort (n=120), VTE developed in 25 patients (20.8%) and did not develop in 95 patients (79.2%). Table 1 and Table 2 show comparisons between VTE cases and patients without VTE for both quantitative and categorical variables. Median INR values at diagnosis and across the first 7 days of induction tended to be lower in patients with VTE and reached significance on days 3-5 (p=0.032 for INR-Day 3, p=0.046 for INR-Day 4, p=0.014 for INR-Day 5). Patients with VTE had a median BMI of 30, while patients without VTE had a median BMI of 28, which approached statistical significance (p=0.055). 8% of patients with VTE (2/25) had a history of VTE prior to the diagnosis of AML, while 3% without VTE (3/95) had a history of previous VTE (OR 2.7, p=0.281). Mutation in genes involved in DNA methylation also conferred an increased risk of VTE, with the association approaching statistical significance (p=0.083). There were no other variables that were significantly different between the two groups. CONCLUSIONSIn this cohort of patients with non-APL AML, there was a trend towards lower INR correlating with an increased incidence of VTE. Additionally, higher BMI, previous history of VTE, and mutation in DNA methylation genes were associated with increased incidence of VTE, though these trends did not reach statistical significance. The pathophysiology of VTE in this setting is likely complex and multifactorial. The shorter INR in those who developed VTE suggests a mechanism independent of the development of DIC, which is distinct from APL. The finding that obesity and personal history of VTE, both known risk factors for thrombosis, were associated with an increased incidence of VTE is also consistent with a non-DIC mechanism. Mutations in DNA methylation genes may have contributed to increased risk of VTE in this cohort; while this association is compelling, further studies with larger sample sizes are needed to confirm this finding. This study was limited by small sample size and missing data, especially regarding available data on coagulation tests. However, this analysis uncovers interesting associations that shed light on the pathophysiology of VTE in AML. More research is needed to further elucidate risk factors for VTE in order to provide optimal supportive care for this patient population. [Display omitted] DisclosuresNo relevant conflicts of interest to declare.

Hypomethylating Agent/Venetoclax Versus Intensive Chemotherapy in Relapsed or Refractory Acute Myeloid Leukemia

Background: Patients with relapsed or refractory (r/r) acute myeloid leukemia (AML) have limited treatment options. Outside of clinical trials and in the absence of a targetable mutation, there is no consensus on an optimal treatment regimen. Venetoclax (Ven), combined with hypomethylating agents (HMA) such as azacitadine (Aza) or decitabine (Dec), is approved as frontline treatment for elderly or unfit patients with AML. HMA/Ven is also being used frequently in the salvage setting. However, outcomes of HMA/Ven compared to IC for patients with r/r AML are largely unknown.Methods: We conducted a retrospective study to compare outcomes of adult patients (>18y) with r/r AML treated with either HMA/Ven or IC at the University of Alabama at Birmingham. Patients treated with HMA/Ven were matched in a 1:1 ratio to patients receiving IC following a hierarchal algorithm based on age, ELN risk stratification, time to relapse (primary refractory/<6m vs. ≥6m) and line of therapy. Treatment with HMA consisted of either Aza 75mg/m 2 for 7 days or Dec 20mg/m 2 for 5 days. Venetoclax was administered at an effective dose of 400mg daily for 21-28 days per cycle (dose adjusted for concomitant azole use).Results: There were 74 patients included in the analysis (HMA/Ven=37, IC=37). The baseline characteristics (Table 1) were well balanced with the exception of increased bone marrow blast percentage in the IC arm (59% vs. 39%, p=0.03). The median age of the IC and HMA/Ven groups was 56y (24-72y) and 63y (22-75y), respectively (p=0.06).Regimens in the IC arm included FLAG (n=16, 43%), FLAG-ida (n=11, 30%), CLAG-M (n=5, 14%), 7+3 (n=3, 8%), HiDAC (n=1, 2.5%) and MEC (n=1, 2.5%). In the HMA/Ven arm, 21 patients (57%) received Aza and 16 (43%) received Dec.The rate of complete remission (CR) was higher for IC (49% vs. 24%, p=0.02) whereas rate of CR with incomplete count recovery (CRi) was higher for HMA/Ven (35% vs. 8%, p=0.001) (Table 2). There was no difference in composite CR (CR+CRi) rates between the two arms (IC 57% vs. 59% HMA/Ven, p=0.8). Additionally, there was no difference in rate of refractory disease (27% vs. 27%, p=0.9) or 30-day mortality (IC 13% vs 11% HMA/Ven, p=0.6) between the two arms. More patients in the IC arm (41%), compared to the HMA/Ven (19%) arm proceeded to allogeneic stem cell transplantation (allo-sct) (p=0.04).The median overall survival (mOS) for the IC arm was 16m, compared to 8m for the HMA/Ven arm (p=0.1) (Figure 1). The mOS for patients with primary refractory/<6m relapse from remission was 10m for IC and 6m for HMA/Ven (p=0.4). The mOS for patients refractory to one cycle of intensive induction (7+3 in approximately 90% cases in both arms) was 20m for the IC arm and 5m for the HMA/Ven arm (p=0.03) (Figure 2). The mOS for patients relapsing ≥6m from remission was 15m for IC and 9m for HMA/Ven (p=0.5). There was no difference in survival based on age, ELN risk stratification or cytogenetics.Conclusion: Overall, there appears to be no significant difference in outcomes between IC and HMA/Ven for patients with r/r AML. Higher CR rates as well as ability to proceed to allo-sct are observed with IC. For patients refractory to the first cycle of intensive induction chemotherapy, a significant survival benefit was observed in those receiving IC compared to HMA/Ven. A second round of induction, preferably with a high-dose cytarabine based regimen, may provide better long term outcomes for these patients. [Display omitted] DisclosuresVachhani: CTI BioPharma Corp: Consultancy; Abbvie: Consultancy; Agios: Consultancy; Blueprint Medicines: Consultancy; Pfizer: Consultancy; Seattle Genetics: Research Funding; Astellas Pharma: Speakers Bureau; Incyte: Consultancy, Speakers Bureau; Novartis: Consultancy; O'Neal Comprehensive Cancer Center, University of Alabama at Birmingham: Current Employment; Jazz Pharmaceuticals: Consultancy.

Genetic Landscape and Clonal Evolution Patterns of CEBPA-Mutated Acute Myeloid Leukaemia Based on Next-Generation Sequencing: A Retrospective Analysis

IntroductionAlthough CCAAT/enhancer binding protein alpha double mutated (CEBPADM) acute myeloid leukemia (AML) is considered a low-risk form of AML according to 2017 ELN recommendations, relapse remains a major cause of death. To assess the broader prognostic impact of other cancer-associated genes, we sequenced a panel of 40 myeloid disorders-related genes in a 25 patient cohort.Methods16 CEBPADM AML diagnosis samples along with 9 CEBPAsingle mutated (SM) were analyzed by targeted next-generation sequencing (Ion Torrent) using Oncomine Myeloid Research Assay. 4 CEBPADM and 2 CEBPASM AML relapse samples were analyzed as well. All patients received intensive chemotherapy according to 2017 ELN recommendations.ResultsWith a median follow-up of 3.2 years (range 0.4-12) 5y OS was 61% and 14% for CEBPADM and CEBPASM patients respectively. Overall, a median of 3 concurrent mutations were present at diagnosis, slightly more in CEBPA SM patients (4 vs 3 in CEBPA DMpatients). The number of somatic mutations influenced both PFS and OS (p = 0.04 and p < 0.01 respectively) independently of CEBPA mutational status. Each single unitary increase in the number of mutations increased the hazard for death of 27.7% (95% CI: -1.4-+65; p = 0.064) while passing from 4 to 5 mutations increased the odds of death by 367%. 5y OS in patients with 5 or more concurrent mutation was 14.3% vs 61.8% in patients with less than 5 co-mutated genes; 5y PFS was 0% vs 38.6%.Mutational landscape of CEBPADMand CEBPASMAML differed significantly, with GATA2, FLT3, DNMT3A and TET2 being the most frequently mutated genes in CEBPADM vs NPM1, FLT3, DNMT3A and WT1 in CEBPASM patients. NPM1(77.8% vs 6.7%; p < 0.01) and ASXL1 mutations (44.4% vs 0%; p = 0.02) were more frequent in CEBPASM patients, confirming they are mutually exclusive with CEBPA biallelic lesions. DNA methylation was the most frequently mutated pathway in biallelic patients (87%) while chromatin/cohesin complex (88%) was the most frequently mutated one in CEBPA monoallelic patients. Mutations of CEBPA, NPM1, DNMT3A, WT1, STAG2, TET2, ASXL1, IDH2, SRSF2, CALR, PRPF8, NF1, TP53, RUNX1 had the highest median variant allele frequency (VAF), more often representing founding mutations. GATA2, IDH1, KRAS, BCOR, MPL, IKZ2F1 and PTPN11 had a more borderline median VAF, variably being clonal or subclonal. Mutations in the 3 tyrosine kinases genes FLT3-ITD , CSF3R, NRAS were only subclonal.Mutations in WT1 and FLT3 were associated with increased relapse rate (p = 0.02 and p = 0.01 respectively), while patients with GATA2 mutations had a strong trend towards better 5y OS (83% vs 32%, p = 0.053).We also identified a not previously described allelic variant in the SH2B3 gene (ATGGGG/A INDEL) with an overall prevalence in our population of 58.3% (46.7% of CEBPA DM and 77.8% of CEBPA SMpatients). Patients with the SH2B3allelic variant had a significantly lower bone marrow blast percentage at diagnosis (p = 0.014) and a strong trend towards a higher number of concurrent mutations (p = 0.056). Moreover, when present at diagnosis, SH2B3 variant persisted at relapse with the same VAF. By real time PCR we demonstrated that this SH2B3 allelic variant leads to a dramatic reduction of the corresponding transcript. This gene encodes for a negative regulator of many crucial signaling pathways (SCF/c-KIT, erythropoietin/JAK2, thrombopoietin/MPL WT/ W515L, JAK2 WT/ V617F, GM-CSFR and FLT3-WT/ITD) of the hematopoietic stem cell.Matched diagnosis and relapse samples analysis suggested different features of clonal evolution: while mutations of SH2B3, WT1, DNMT3A, NPM1, and IDH1 consistently persisted at relapse, CEBPA and GATA2 mutations were unstable during disease course. ZRSR2 and PRPF8 mutations were found in relapse samples only.SummaryOur study offers insights into the genetic landscape of CEBPADM mutated AML as compared to CEBPASM AML, highlighting the contribution of NGS to risk stratification. In fact, our data show that the number and the type of concurrent mutation has a prognostic impact, possibly identifying patients eligible to first line allogeneic stem cell transplantation. We identified an allelic variant of SH2B3 that had never been functionally characterized nor associated with AML and that could represent a marker for genetic instability and a potential new target in AML treatment strategies. [Display omitted] DisclosuresNo relevant conflicts of interest to declare.

FLT3-Mutated Acute Myeloid Leukemia Using a Novel Regimen of Gemtuzumab Ozogamicin and Midostaurin in Combination with Standard Cytarabine and Daunorubicin Induction Therapy

FLT3-Mutated Acute Myeloid Leukemia Using a Novel Regimen of Gemtuzumab Ozogamicin and Midostaurin in Combination with Standard Cytarabine and Daunorubicin Induction Therapy

Clinical Characteristics and Outcomes of Patients Diagnosed with Acute Myeloid Leukemia with Expression of CD71

IntroductionAcute myeloid leukemia (AML) is a clonal hematologic malignancy characterized by the proliferation and accumulation of blasts in the bone marrow (BM) which results in hematopoietic failure. Transferrin receptor (CD71) plays an important role by up-taking iron into the cell, and its expression is regulated by cellular iron levels. Recently, CD71 has emerged as a sensitive and specific marker of cell proliferation in solid tumors. The clinical significance of CD71 expression in AML remains unclear. Current efforts are also exploring its potential as a therapeutic target in AML. We aimed to describe the clinical characteristics and outcomes of patients diagnosed with de novo AML who expressed CD71.MethodsWe conducted a retrospective analysis of 453 patients with newly diagnosed AML that came to our institution from December 2019 to June 2021 in whom CD71 antibody was available at diagnosis. CD71 expression was assessed by flow cytometry immunophenotypic studies performed using bone marrow aspirate specimens at presentation. For each analysis, a minimum of 200,000 events was acquired on FACSCanto II instruments (8-color and 10-color, BD Biosciences). The CD45 dim-blast region including monocytes based on CD45 / side scatter was analyzed. The antibody panel included 5 tubes; CD71 antibody was included in tube 3, which contains the following antigen combination: CD41/CD71/CD56/CD34/CD64/HLA-DR/CD14/CD45. The neoplasm was CD71-positive if at least 20% of blasts demonstrated CD71 expression. Additionally, frontline treatment was categorized into intensive chemotherapy (HiDAC based), and Low-Intensity regimen (double nucleoside analog or hypomethylating agent-based therapies). Outcomes in terms of survival and treatment response were analyzed and reported by age, ELN risk groups (Favorable, Intermediate, and Adverse), and the presence of somatic mutations.ResultsBaseline characteristics are detailed in table 1. We identified 359 (79%) patients diagnosed with AML in whom CD71 was expressed. Our study focused on 184 (41%) patients diagnosed with previously untreated de novo AML, the median age was 63 years (IQR 50-73). Fifty-seven percent of patients were male. Median hemoglobin and platelet counts were 8.2 g/dL and 40 x10 9/L, respectively. The Median BM blast percentage was 54%, among these patients, there was a higher representation of patients with adverse risk features when compared with the intermediate and favorable group (50%, 34%, and 16% respectively). The molecular landscape of our population showed higher representation of RAS (25%), DMNT3A (23%), TP53 (21%), WT1 (21%), NPM1 (20%), FLT3-ITD (16%), and IDH2 (15%), figure 1. Frontline treatment information was available on 108 patients, of these, 43% were treated with intensive chemotherapy, while 57% of patients were treated with a low-intensity regimen.In terms of outcomes, with a median follow-up time of 6 months, the median overall survival of the whole patient cohort was 9 months (95% CI: 4.3-13.6). Patients aged more than 60 years showed inferior OS compared to younger patients (6 vs. 14 months; p=0.059), respectively, figure 2. Among patients with adverse risk features, the median OS was 5 months (95% CI: 3-6.9, p=0.068) versus those with intermediate (12 months) and favorable risk features (16 months), figure 3. Next, among the somatic mutations with higher representation with known prognostic impact, patients with TP53 mutated showed a significantly inferior OS compared to those with wild type (median 4 vs. 12 months, p=0.006) respectively, figure 4. Patients treated with intensive chemotherapy showed a trend to higher ORR versus low-intensity regimen (89% vs. 74% respectively, p=0.051). Similarly, CR/CRi rates were higher among those treated with intensive chemotherapy compared to those with a low-intensity regimen (85% vs. 70% respectively, p=0.106), figure 5.ConclusionAcute myeloid leukemia is an aggressive hematologic malignancy with a heterogeneous nature. CD71 expression appears to be a common event and was identified in up to 40% of de novo AML cases in our institution. Its expression appears to be associated with cytopenias in addition to the presence of molecular abnormalities commonly associated with an adverse prognosis. Its clinical significance, applicability as a diagnostic marker, and potential as a therapeutic target in AML need to be fully elucidated. [Display omitted] DisclosuresAlvarado: Astex Pharmaceuticals: Research Funding; Jazz Pharmaceuticals: Research Funding; BerGenBio: Research Funding; CytomX Therapeutics: Consultancy; MEI Pharma: Research Funding; Daiichi-Sankyo: Research Funding; FibroGen: Research Funding; Sun Pharma: Consultancy, Research Funding. Kantarjian: Immunogen: Research Funding; Astra Zeneca: Honoraria; Ipsen Pharmaceuticals: Honoraria; Jazz: Research Funding; Amgen: Honoraria, Research Funding; Astellas Health: Honoraria; Aptitude Health: Honoraria; Novartis: Honoraria, Research Funding; KAHR Medical Ltd: Honoraria; NOVA Research: Honoraria; BMS: Research Funding; Ascentage: Research Funding; AbbVie: Honoraria, Research Funding; Daiichi-Sankyo: Research Funding; Pfizer: Honoraria, Research Funding; Precision Biosciences: Honoraria; Taiho Pharmaceutical Canada: Honoraria.

Immune and Epigenetic Landscape of TP53-mutated Acute Myeloid Leukemia (AML) and Higher-Risk Myelodysplastic Syndromes (HR-MDS)

Immune and Epigenetic Landscape of TP53-mutated Acute Myeloid Leukemia (AML) and Higher-Risk Myelodysplastic Syndromes (HR-MDS)

Frequency of FLT3 Internal Tandem Duplications in Adult Syrian Patients with Acute Myeloid Leukemia and Normal Karyotype.

Objective:Activating mutations of the fms-like tyrosine kinase 3 gene (FLT3) by internal tandem duplications (ITDs) in the juxtamembrane domain (JMD) have been reported in ~30% of adult acute myeloid leukemia (AML) patients with cytogenetically normal karyotype (CN). However, FLT3/ITD mutations are frequently accompanied with leukocytosis, high percentage of blasts in bone marrow (BM), and increased the risk of treatment failure in AML patients. FLT3-ITD mutated AML patients mainly with normal karyotype have higher relapse probability and shorter duration of complete remission (CR) after chemotherapy, so FLT3-ITD mutation is considered as an independent poor prognostic factor in AML. Methods: FLT3-ITD and FLT3-KTD were studied by polymerase chain reaction (PCR) and restriction fragment length polymorphism- PCR (RFLP-PCR) in 44 adults AML patients with cytogenetically normal karyotype (AML-CN) at diagnosis to characterize FLT3 status. The results were correlated with the prognostic factors. Results:In this study, FLT3-ITD mutations were identified in 7 (15.9%) of the 44 AML-CN patients. Among the 7 patients with FLT3/ITD mutations, 6 patients revealed a typical ITDs mutation (fragment size was 329 bp) and one patient showed untypical ITD mutation (fragment size was ~400 bp). Whereas 37 patients (61.7%) were FLT3-ITD. None of all AML-CN patients examined showed FLT3-KTD mutations. Conclusions:Our results support that FLT3-ITD are independent adverse prognostic factors for elderly AML-CN patients and are associated with low overall survival (OS), low rate of CR, high relapse rate (RR), and high percentage of BM blast at diagnosis. We concluded, FLT3 mutation analysis should be performed as a routine test in AML-CN patients.

ALL-003: Value of Autophagy Related Gene 5 (ATG5) Expression as a Prognostic Marker in Adult Patients with Newly Diagnosed Acute Lymphoblastic Leukemia (ALL)

Context: Autophagy is considered a pivotal cellular mechanism to cope with stress and maintain homeostasis. It is frequently dysregulated in different types of cancers with some exhibiting excessive and others having reduced autophagy levels. Objectives: To determine autophagy status in newly diagnosed adult acute lymphoblastic leukaemia (ALL) patients compared to age and sex matched controls. Moreover, its prognostic impact on disease characteristics and response to treatment was evaluated. Design: Prospective study. The patients were followed up to 12 months. Setting: Clinical Hematology and Oncology unit, Internal Medicine department, Faculty of Medicine, Ain Shams University, Cairo, Egypt. Patients: Thirty-five newly diagnosed adult ALL patients were recruited and age and sex matched to 15 healthy control subjects. Intervention: ATG5 expression was measured on diagnosis using real-time quantitative polymerase chain reaction (qPCR). Cases have been followed up for one year after enrollment into the study. Main Outcome Measures:: To measure ATG5 in newly diagnosed ALL patients and correlate its level with clinical outcome and treatment response. Results: Mean ATG5 expression in ALL was twice that of controls which exhibits high statistically significant difference (2.15 + 2.2 vs 1.09 + 0.47, P value = 0.01). Its high expression has been significantly associated with B-ALL phenotype, lower haemoglobin and lower platelet counts. Of note, higher expressor group had higher bone marrow and peripheral blood blast percentages, more likelihood to develop chemoresistance to frontline agents; however, this did not show statistical significance. Further studies with the recruitment of larger sample of patients is needed to examine a relationship between autophagy activation and therapeutic outcome in ALL. Conclusion: Our study demonstrates that classic autophagic pathway may be activated in ALL patients and that it may be associated with more aggressive tumour behaviour and worse outcome.

AML-248: Clinico-Pathological Profile of Therapy-Related Acute Myeloid Leukemia

<h3>Context:</h3> Secondary acute myeloid leukemia (sAML) may arise from a previous clonal disorder of hematopoiesis, usually from myelodysplastic syndrome, chronic myeloproliferative neoplasm, or as a complication in patients receiving chemotherapy or radiotherapy for a primary malignancy, including hematological and non-hematological/solid malignancies (therapy-related AML [t-AML]). Overall, frequencies of sAML and tAML were 19.8% and 6.6%, respectively. It is associated with specific clinical features with a uniformly poor prognosis. <h3>Objective:</h3> To study patients of t-AML with respect to clinical presentation, laboratory parameters (including flow cytometry immunophenotyping), cytogenetic and molecular studies, and clinical outcome. <h3>Design:</h3> This study was a retrospective analysis of patients of t-AML from January 2011 to December 2019. <h3>Patients:</h3> The patients underwent a detailed hematological work up: peripheral blood smear, bone marrow examination along with flow cytometric immunophenotyping, and karyotyping and molecular studies (NPM1, FLT3ITD/TKD, BCR/ABL, PML/RARA, INV16, AML-ETO). Outcomes of the patients were also reviewed. <h3>Results:</h3> A total of 20 cases of therapy-related AML were diagnosed in patients treated for various malignancies of the breast (9 cases), prostate (3 cases), and pancreas (2 cases), as well as lymphomas (NHL: 4 cases and HL: 2 cases). There were 7 males and 13 females (M:F: 1:1.85) with a median age of 63 years (range 35–82 years). Median latency period to t-AML was 3.5 years (range 0.5–11.0 years). Median haemoglobin was 72.5 g/L (61–151 g/L), WBC count 3.7× 10⁹/L (1.02–169.1×10⁹/L), platelet count 40 × 10⁹/L (12–257 ×10⁹/L, peripheral blood and bone marrow blast percentage 48% (5-98%) and 76% (20–98%), respectively. AML with monocytic differentiation was the most common morphological and flow cytometric subtype (50% cases). Complex karyotype was seen in 50% cases. Molecular studies for NPM, FLT3ITD/TKD, PML/RARA, AML-ETO, and INV16 showed 8 cases with NPM1 positivity and 4 case with FLT3ITD positivity. Only 4 patients (20%) achieved complete remission but relapsed within 1 year of duration. Ten patients succumbed to their disease, the majority within 1 year of t-AML diagnosis. <h3>Conclusion:</h3> The study highlights the development of therapy-related AML following chemotherapy and/or radiotherapy as an important therapy-related complication. The latency period and clinical manifestations may differ depending on the type of cytotoxic drug, cumulative dose, and dose intensity. A close hematological follow-up should always be done for an accurate and timely diagnosis.