Clinical Lymphoma, Myeloma & Leukemia, Vol.22, Suppl.2 - October 2022

Abstracts Clinical Lymphoma, Myeloma & Leukemia October 2022 S226 + Sorafenib on November 6th, 2021. Again, he could not achieve a response and received FLAG (high-dose cytosine arabinoside, fludarabine, and granulocyte colony-stimulating factors) + Sorafenib on December 18th, 2021, after recovery from COVID-19 infection. Mai n Outco m e Measures: To shed light on fact that myeloid neoplasms as MPN, MDS, and de novo AML can share overlapping features. Results: On January 25th, 2022, the last CBC showed a Hb level of 8.4 g/dL, a platelet Count of 395×10 9 /L, and a WBC Count of 2.41×10 9 /L with a differential Neutrophil count of 0.24×10 9 /L. The patient lost follow-up since then. Co n clusio n s: Only a few AML cases have been reported with thrombocytosis. Detailed molecular studies are mandatory to confirm the diagnosis of de novo AML patients with unusual presentation. Careful follow- up of those cases could help in establishing management guidelines for better outcomes as those patients usually have a poor prognosis. Keywords: AML, MPN, MDS, thrombocytosis, case AML-226 Impairment of Primary Hemostasis as an Additional Risk Factor of Hemorrhage in Patients With Newly Diagnosed Acute Myeloid Leukemia: Ukrainian Prospective Study Zinaida Stupakova MD 1 , Iryna Dyagil PhD 1 , Zoya Martina PhD 1 , Anna Sergeieva MD 1 , Oksana Karnabeda PhD 2 , Ulyana Melnyk MD 3 , Olga Novosad PhD 4 1 State Institution “National Research Center for radiation Medicine of NAMS of Ukraine”, Kyiv, Ukraine. 2 Bohomolets National Medical University, Kyiv, Ukraine. 3 Kyiv City Clinical Hospital No.9, Kyiv, Ukraine. 4 National Cancer Institute, Kyiv, Ukraine Backgrou n d: Bleeding events in acute myeloid leukemia (AML) are frequent and life threatening, whereas widely used treatment approaches are not always able to satisfy expected outcomes. Study Ai m : The primary endpoints were the qualitative and quantitative functions of plasma von Willebrand factor (vWF), which include measurements of vWF activity (vWF:ristocetin cofactor [vWF:RCo]), vWF level (vWF:antigen [vWF:Ag]), factor VIII coagulation activity regarding vWF (vWF:FVIII), and FVIII activity (FVIII) in AML patients. Patie n ts a n d Methods: Forty-two patients with newly diagnosed AML (excluding acute promyelocytic leukemia) were included in the study group. The control group included 20 age-matched and sex-matched healthy individuals. The grade (G) of bleeding events was assessed according to the Modified WHO Bleeding Scale (WHO BS). Results: Hemorrhage (G1–4) occurred in 53.3% of patients in the study group during induction therapy. vWF:Ag below normal ranges had been observed in 19% of patients with AML and was associated with the occurrence of severe hemorrhage compared with the patients who had normal vWF:Ag levels and no bleeding episodes ( P =0.012). It is important to mention that vWF:Ag levels (median 134, mean 163±18.25) were elevated in most cases (56%) in the main group and are probably associated with a compensatory mechanism for stopping bleeding compared with the control group. In 23.8% of patients with AML, we observed levels of vWF:RCo below normal ranges. Among them, the most frequent bleeding events were G2 (5/10, 50%) and G4 (3/10, 30%); three of them died during the first course of chemotherapy due to gastrointestinal and CNS bleeding. Therefore, we found a statistically significant association between decreased levels of vWF:RCo below normal ranges and the occurrence of severe bleeding episodes (G2–G4) in patients with AML compared with the group that had normal ranges of vWF:RCo and no bleeding events (G0) ( P =0.0001). Furthermore, low vWF:FVIII ( P =0.033) and FVIII ( P =0.03 7 ) levels in patients with AML and bleeding episodes G2–G4 had statistical differences compared to non-hemorrhage patients (G0). Co n clusio n s: According to our study, vWF:RCo, vWF:Ag, and vWF:FVIII were associated with hemorrhage in patients with newly diagnosed AML and could be considered predictive factors of bleeding. Keywords: AML, von Willebrand factor, hemorrhage, bleeding events AML-230 Predictive Value of CD34-Positive versus CD34-Negative Leukemic Stem Cells on Survival Outcome in Acute Myeloid Leukemia Nupur Das MD, Devasis Panda MD, Ritu Gupta MD, Smeeta Gajendra MD, Sameer Bakhshi MD, Atul Sharma DM, Ranjit K Sahoo DM, Lalit Kumar DM, Sandeep Rai PHD, Vijay K Prajapati MSC, Saroj Singh MSC All India Institute of Medical Science, New Delhi, India Co n text: Leukemic stem cells (LSCs) have emerged as a potential factor contributing to an overall dismal outcome in acute myeloid leukemia (AML). Objecti v e: In this study, using flowcytometric immunophenotyping (FCMI), we have demonstrated LSC identification and quantification in both the CD34+ and CD34− compartments to find its relevance in predicting treatment outcomes. Furthermore, we correlated the impact of LSC quantification at diagnosis as a predictor of long-term survival. D esig n : This is a prospective analysis of patients diagnosed with AML (per standard WHO criteria). Setti n g: Tertiary care cancer center. Patie n ts: A total of 161 patients with a diagnosis of non–acute promyelocytic leukemia (non-APL) AML patients diagnosed over a period of two years (January 2019 to December 2020) were evaluated. I n ter v e n tio n s: Bone marrow aspirates collected in EDTA were processed for FCMI using a stain-lyse-wash technique with a single- tube, 10-color comprehensive antibody panel. LSCs were identified primarily in the CD34+CD38− compartment; however, in a substantial number of CD34− AML, LSCs were segregated from the CD34−CD38− compartment using CD11 7 as an alternate gating marker and CD123, CD33, and CD11b as LSC-specific markers in all cases. Mai n Outco m e Measures: 1. CD34+ versus CD34− LSC and 2. Baseline LSC% as a predictor of survival. Results: LSCs were identified in 82.6% (133/161) of patients. CD34+ LSCs and CD34− LSCs were isolated in 82.53% (104/126) and 82.85% (29/35) of cases, respectively. The median survival times (in weeks) in CD34− LSCs was higher than in CD34+ LSCs; EFS (54 vs. 4 7 ;