Frequency and risk factors for thrombosis in acute myeloid leukemia and high-risk myelodysplastic syndromes treated with intensive chemotherapy: a two centers observational study

Clinical analysis of bleeding and thrombotic events in haematological-oncology patients with severe thrombocytopenia and a high risk of thrombosis

BACKGROUND

Haematological patients with severe thrombocytopenia and high thrombotic risk face challenges related to balancing bleeding and thrombosis risks. This study investigated factors associated with bleeding and thrombosis in high-risk haematological oncology patients with severe thrombocytopenia not receiving anticoagulant therapy and characterized their clinical features when both events occurred.

METHODS

A total of 446 haematological oncology patients with Caprini scores ≥ 5 were included from July 2022 to June 2023 at Mianyang City Central Hospital. Those not receiving prophylactic anticoagulants due to an admission platelet count < 50 × 109/L were studied. Patients were categorized into bleeding/nonbleeding and thrombotic/nonthrombotic groups on the basis of hospital course. Relevant clinical data were collected, and univariate/multivariate logistic regression was used to analyse the influencing factors. The platelet count at admission was assessed via ROC curves for thrombosis prediction.

RESULTS

In the bleeding group, higher proportions of patients with leukaemia, myeloid tumours, lung infections, and a central venous catheter (CVC) with two lumens were observed, along with shorter catheter durations, lower initial and minimum platelet counts during hospitalization, and prolonged plasminogen times (all P < 0.05). The thrombotic group had a greater thrombosis history, initial platelet count, use of two venous catheter lumens, parenteral nutrition, sedation, and autologous haematopoietic stem cell transplantation (Auto-HSCT), with a lower leukaemia proportion (P < 0.05). Logistic regression identified lymphoma type and minimum platelet count as bleeding protective factors and the Charlson Comorbidity Index (CCI) score as an independent risk factor. Thrombosis history, two venous catheter lumens, and sedation were risk factors for thrombosis. The median platelet count was lower at bleeding and thrombosis than at admission (P = 0.007). The platelet count at admission had predictive value for thrombosis, especially severe thrombocytopenia, with an AUC of 0.735 (95% CI 0.613-0.858, P = 0.003) and a cut-off value of 42.5 × 109/L.

CONCLUSIONS

For haematological neoplasm patients with a high risk of venous thromboembolism (VTE), severe thrombocytopenia and high CCI scores, risk prevention and control of bleeding take precedence over thrombosis prophylaxis. Prophylactic anticoagulation is still recommended for patients with lymphoma assessed at high risk for VTE and with platelet counts of at least 42.5 × 109/L.

Cancer-associated thrombosis in hematologic malignancies

Patients with hematologic malignancies are often complicated not only by severe bleeding due to thrombocytopenia and disseminated intravascular coagulation but also by thromboembolic events, just like in patients with solid cancers, and these events can negatively impact patient outcomes. Nevertheless, the prevention and treatment of cancer-associated thrombosis (CAT) in hematologic malignancies has not been adequately investigated due to the limited size, heterogeneity, and unique pathophysiology of the patient population. This article summarizes the current understanding, risk factors, prediction models, and optimal prevention and treatment strategies of CAT in hematologic malignancies on a disease-by-disease basis, including acute leukemia, lymphoma, myeloma, and myeloproliferative neoplasms. Specific considerations of novel molecular targeted therapeutics introduced in recent years, such as immunomodulatory drugs and tyrosine kinase inhibitors, are also discussed based on the latest clinical trials.

Venous thromboembolism in patients with acute myeloid leukemia: development of a predictive model

BACKGROUND

Patients with acute myeloid leukemia (AML) are at increased risk of venous thromboembolic events (VTE). However, thromboprophylaxis is largely underused.

OBJECTIVES

This study aimed to determine possible VTE development risk factors and to develop a novel predictive model.

METHODS

We conducted a retrospective cohort study of adult patients with newly diagnosed AML. We used univariate and multivariable logistic regression to estimate binary outcomes and identify potential predictors. Based on our final model, a dynamic nomogram was constructed with the goal of facilitating VTE probability calculation.

RESULTS

Out of 626 eligible patients with AML, 72 (11.5%) developed VTE during 6 months of follow-up. Six parameters were independent predictors: male sex (odds ratio [OR] 1.82, 95% confidence interval [CI]: 1.077-2.065), prior history of thrombotic events (OR 2.27, 95% CI: 1.4-4.96), international normalized ratio (OR 0.21, 95% CI: 0.05-0.95), Eastern Cooperative Oncology Group performance status (OR 0.71, 95% CI: 0.53-0.94), and intensive therapy (OR 2.05, 95% CI: 1.07-3.91). The C statistics for the model was 0.68. The model was adequately calibrated and internally validated. The decision-curve analysis suggested the use of thromboprophylaxis in patients with VTE risks between 8 and 20%.

CONCLUSION

We developed a novel and convenient tool that may assist clinicians in identifying patients whose VTE risk is high enough to warrant thromboprophylaxis.

Arterial Thromboembolism in Japanese Patients With Cancer: Incidence, Predictors, and Survival Impact

Background

Thromboembolism is a significant complication for patients with cancer, leading to treatment interruptions and poor outcomes.

Objectives

The aim of this study was to investigate the incidence of arterial thromboembolism (ATE) within cancer populations, identify the predictors of ATE, and determine its survival impact.

Methods

A retrospective multicenter study was performed using data from the Osaka Cancer Registry linked with administrative data from 2010 to 2015. Patients were monitored for 5 years after cancer diagnosis, and ATE incidence was calculated with death as a competing risk. Fine and Gray competing risk regression models and Cox proportional hazards models were used to evaluate the predictors of ATE and the survival impact. Restricted mean survival time (RMST) was used to assess whether antithrombotic therapy after ATE contributed to improved survival.

Results

The cohort comprised 97,448 patients with cancer (42.3% women, median age 70 years). ATE incidence displayed an annual increase, peaking 1 year after cancer diagnosis (1-, 2-, 3-, 4-, and 5-year cumulative incidences were 1.29%, 1.77%, 2.05%, 2.22%, and 2.32%, respectively). Male sex, advanced age, advanced cancer stage, and hematologic malignancies correlated with a high risk for ATE. Patients with ATE had a 2-fold increased risk for mortality compared with those without ATE. The 90-day and 1-year RMST differences for those on antithrombotic therapy were 13.3 days (95% CI: 10.4-16.2 days; P < 0.001) and 57.8 days (95% CI: 43.1-72.5 days; P < 0.001), favoring the antithrombotic therapy group. The RMST differences varied by cancer stage.

Conclusions

The risk for ATE varies according to sex, age, and cancer progression and type. Antithrombotic therapy after ATE is associated with improved survival among patients with cancer.

The ISTH DIC-score predicts early mortality in patients with non-promyelocitic acute myeloid leukemia

Coagulation disorders frequently complicate the clinical course of acute myeloid leukemia (AML) patients. This study examined the frequency and prognostic significance, with regards of early mortality, of the presence of overt disseminated intravascular coagulation (DIC) at AML diagnosis and its correlation with clinical and biological characteristics. A retrospective analysis of 351 newly diagnosed non-promyelocytic AML patients was conducted, utilizing the 2018 ISTH DIC-Score criteria to evaluate the presence of overt DIC at AML onset. The study cohort had a median age of 65 years with a predominance of male gender (59 %). Overt DIC was present in 21 % of cases and was associated with advanced age, comorbidities, poor performance status, hyperleukocytosis, LDH levels, NPM1 mutations, expression of CD33 and CD4, and lack of expression of CD34. With a median follow-up of 72 months (3-147 months), the 6-year overall survival (OS) was 17.4 %, with patients having overt DIC showing significantly poorer outcomes (7.2 % compared to 20.3 % of those without DIC, p < 0.001). Patients with overt DIC showed markedly high early mortality rates at 30 (42.5 % vs 8 %), 60 (49.3 % vs 16.9 %), and 120 days (64.4 % vs 25.6 %) from disease onset. In multivariate analysis overt DIC retained its independent prognostic value for early mortality. In conclusion, the prevalence and clinical relevance of DIC in non-promyelocytic AML is not negligible, underlining its potential as an unfavorable prognostic marker. In newly diagnosed patients with AML, early recognition and measure to counteract coagulation disturbances might help mitigate the elevated mortality risk associated with DIC.

Platelet Parameters as Biomarkers for Thrombosis Risk in Cancer: A Systematic Review and Meta-analysis

Cancer-associated thrombosis (CAT) is a major cause of both morbidity and mortality in cancer patients. Platelet count has been investigated as a predictor of CAT in various settings while knowledge on platelet activation parameters is sparse. This report provides a systematic review and meta-analysis on available literature on associations between platelet count and/or function and arterial and venous thrombosis in adult cancer patients. The review was performed according to the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) statement. PubMed and Embase were searched up to March 2022. The National Heart, Lung, and Blood Institute's tools were used for quality assessment. In total, 100 studies were included which investigated the association between CAT and platelet count (n = 90), platelet indices (n = 19), and platelet function/activation markers (n = 13) in patients with solid cancers (n = 61), hematological cancers (n = 17), or mixed cancer types (n = 22). Eighty-one studies had venous thrombosis as their outcome measure, while 4 had arterial thrombosis and 15 studies had both. We found significantly elevated odds ratio of 1.50 (95% confidence interval: 1.19-1.88) for thrombosis with higher platelet counts. We saw a tendency toward an association between markers of platelet activation in forms of mean platelet volume and soluble P selectin and both arterial and venous thrombosis. Only one study investigated dynamic platelet function using flow cytometry. In conclusion, platelet count is associated with CAT across different cancer types and settings. Platelet function or activation marker analysis may be valuable in assisting thrombosis risk assessment in cancer patients but is sparsely investigated so far.

Acute myocardial infarction in an untreated patient with acute myeloid leukemia

Key Clinical Message

Acute leukemia, particularly AML, is closely associated with thrombotic events, driven by complex factors like coagulation system changes, endothelial dysfunction, and leukemic cell interactions with the vascular system. Certain chemotherapy drugs can exacerbate the prothrombotic state. Understanding these dynamics is crucial for effective thromboprophylaxis in carefully selected patients with leukemia.

Abstract

Thrombosis is a significant complication of acute leukemia. Thrombotic events mostly occur at diagnosis or during induction therapy. Here we report the occurrence of myocardial infarction (MI) before initiation of therapy, in a patient with acute myeloid leukemia not otherwise specified (AML NOS) who had no other significant risk factors for coronary artery disease. The occurrence of MI in this patient limited the choice of induction therapy and resulted in mortality. We discuss the pathogenesis and risk factors associated with increased thrombosis in AML and advocate for risk-adapted thromboprophylaxis in this patient population.

Right femoral vein and right dorsal artery thrombosis in childhood acute myeloid leukemia: A case report

BACKGROUND

It is rare for newly diagnosed (de novo) or newly treated acute myeloid leukemia (AML) complicated with thrombotic complications, especially combined arterial and venous thrombosis.

METHODS

We reported a 13-year-old boy diagnosed with AML and leukocytosis, who developed right femoral vein and right dorsal artery thrombosis during chemotherapy. After treatment with low molecular weight heparin, diosmin, and alprostadil, symptoms were relieved. Unfortunately, the child suffered from coagulopathy afterward, which was unexpectedly caused by vitamin K deficiency.

RESULTS

After supplementation with vitamin K and prothrombin complex concentrate, coagulation function recovered.

CONCLUSION

For childhood AML patients with high thrombotic risks, close monitoring during anticoagulant treatment was necessary. Concomitantly, we should be alert to past medication history and combined medication use, especially those that may lead to vitamin K deficiency, secondary bleeding, and coagulation disorders. Rational use of antibiotics, anticoagulants, and antitumor drugs must be guaranteed.

Regulation of coagulation activation in newly diagnosed AML by the heme enzyme myeloperoxidase

INTRODUCTION

Patients with acute myeloid leukemia (AML) are at increased risk of thrombohemorrhagic complications. Overexpressed tissue factor (TF) on AML blasts contributes to systemic coagulation activation. We have recently shown that the heme enzyme myeloperoxidase (MPO) negatively regulates TF procoagulant activity (PCA) on myelomonocytic cells in vitro. We now aimed to further characterize the functional interaction of MPO and TF in AML in vivo.

METHODS

We prospectively recruited 66 patients with newly diagnosed AML. TF PCA of isolated peripheral blood mononuclear cells (PBMC) was assessed by single-stage clotting assay in the presence or absence of inhibitors against MPO catalytic activity (ABAH) or against MPO-binding integrins (anti-CD18). MPO in plasma and in AML blasts was measured by ELISA, and plasma D-dimers and prothrombin fragment F1+2 were quantified by automated immunoturbidimetric and chemiluminescence assays, respectively.

RESULTS

Patients with AML had significantly higher MPO plasma levels compared to healthy controls and exhibited increased levels of D-dimers and F1+2. In vivo thrombin generation was mediated by TF PCA on circulating PBMC. Ex vivo incubation of isolated PBMC with ABAH or anti-CD18 antibody resulted in either increased or decreased TF PCA. The strong and robust correlation of F1+2 with TF PCA of circulating PBMC was abrogated at MPO plasma levels higher than 150 ng/mL, indicating a modulatory role for MPO on TF-mediated in vivo thrombin generation above this threshold.

CONCLUSION

Our study indicates that catalytically active MPO released by circulating myeloblasts regulates TF-dependent coagulation in patients with newly diagnosed AML in a CD18-dependent manner.

Arterial Thrombosis in Patients with Acute Myeloid Leukemia: Incidence and Risk Factors

BACKGROUND

Patients with hematological malignancies have an increased risk of arterial thrombotic events (ATEs) after diagnosis, compared to matched controls without cancer. However, data about incidence and risk factors for ATE development in patients with acute myeloid leukemia (AML) are missing.

AIM

The objectives of this study were to determine the incidence of ATE in non-promyelocytic-AML patients and to define the potential risk factors for ATE development.

METHODS

We conducted a retrospective cohort study of adult patients with newly diagnosed AML. The primary outcome was the occurrence of confirmed ATE, defined as myocardial infarction, stroke or critical limb ischemia.

RESULTS

Out of 626 eligible AML patients, 18 (2.9%) patients developed ATE in the median time of 3 (range: 0.23-6) months. Half of these patients died due to ATE complications. Five parameters were predictors of ATE: BMI > 30 (p = 0.000, odds ratio [OR] 20.488, 95% CI: 6.581-63.780), prior history of TE (p = 0.041, OR 4.233, 95% CI: 1.329-13.486), presence of comorbidities (p = 0.027, OR 5.318, 95% CI: 1.212-23.342), presence of cardiovascular comorbidities (p < 0.0001, OR 8.0168, 95% CI: 2.948-21.800) and cytogenetic risk score (p = 0.002, OR 2.113, 95% CI: 1.092-5.007).

CONCLUSIONS

Our study showed that patients with AML are at increased risk of ATE. The risk was increased in patients with cardiovascular comorbidities, previous thrombosis, adverse cytogenetic risk as well as BMI > 30.

Editorial to the Special Issue "Recent Advances in Biochemical Mechanisms of Acute Myeloid Leukemia"

Acute myeloid leukemia (AML) is a clonal malignant disorder of myeloid progenitor cells characterized by uncontrolled proliferation, dysregulation in the differentiation program, and inhibition of apoptosis mechanisms [...].

Early-onset venous thromboembolisms in newly diagnosed non-promyelocytic acute myeloid leukemia patients undergoing intensive induction chemotherapy

OBJECTIVES AND METHODS

Venous thromboembolic (VTE) events are emerging as frequent complications in acute myeloid leukemia (AML); however, there is insufficient data regarding epidemiology, risk factors, and impact on outcomes. The optimal approach to balance risks of thrombosis and hemorrhage remains unclear. This retrospective single-center study in AML patients undergoing induction chemotherapy between 2007 and 2018 assessed incidence, risk factors, features, and outcomes of early-onset VTE.

RESULTS

423 patients (median age 59 years) were enrolled. VTE was diagnosed in 31 patients (7.3%) within 3 months of admission. The median time to VTE was 3 days. Non-central venous catheter (CVC)-related VTE occurred in 19 patients (61%). Main risk factor for VTE was leukocytosis at admission, independent of platelet counts/INR. Four patients (13%) exhibited VTE recurrence. No deaths directly related to VTE or major bleeding events associated with platelet-adjusted anticoagulation in patients with VTE were recorded. There was no clear impact of VTE on 1-year overall survival; however, non-CVC-related VTE may be associated with adverse outcomes.

CONCLUSIONS

Early-onset VTE is a common complication in newly diagnosed AML patients admitted for induction chemotherapy. Leukocytosis is an independent VTE risk factor. The potentially adverse impact of non-CVC-related VTE merits further study.

The occurrence of thrombosis during intensive chemotherapy treatment for acute myeloid leukemia patients does not impact on long-term survival

Venous thromboembolism (VTE) is frequently seen in acute myeloid leukemia (AML) patients and presents a significant clinical challenge. The association of VTE during intensive chemotherapy with risk models such as the Medical Research Council (MRC) cytogenetic-based assessment and the European LeukemiaNet (ELN) 2017 molecular risk model have not been rigorously evaluated. Additionally, there is a paucity of data pertaining to the long-term prognostic impact of VTE in AML patients. We performed an analysis of baseline parameters of AML patients diagnosed with VTE during intensive chemotherapy and compared them with patients without VTE. The analyzed cohort consisted of 335 newly diagnosed AML patients with a median age of 55 years. Thirty-five patients (11%) were classified as MRC favorable risk, 219 (66%) patients as intermediate risk, 58 patients (17%) as adverse risk. Per ELN 2017, 132 patients (40%) had favorable risk disease, 122 patients (36%) intermediate risk, and 80 patients (24%) had adverse risk. VTE was seen in 33 patients (9.9%), occurring mostly during induction (70%), and required catheter removal in 9 patients (28%). Baseline clinical, laboratory, molecular, and ELN 2017 parameters were not significantly different groups. However, MRC intermediate-risk group patients were significantly more likely to experience thrombosis compared to favorable risk and adverse risk patients (12.8% versus 5.7% and 1.7%, respectively; p = 0.049). Median overall survival was not significantly impacted by the diagnosis of thrombosis (3.7 years versus 2.2 years; p = 0.47). VTE is tightly associated with temporal and cytogenetic parameters in AML but does not significantly impact on long-term outcomes.

Venous Thromboembolism in Cancer Patients Undergoing Chemotherapy: A Systematic Review and Meta-Analysis

Objective: Venous thromboembolism (VTE) is a life-threatening complication that may exacerbate cancer prognosis. Whilst some studies indicate an increased risk of VTE in cancer patients undergoing chemotherapy, the prevalence estimates on the pooled prevalence of VTE in cancer patients undergoing chemotherapy are not known. This study aims to calculate the pooled prevalence of VTE in chemotherapy-treated cancer patients. Methods: Studies on VTE occurrence in cancer patients undergoing chemotherapy were retrieved after database search. The terms used included “cancer”, “chemotherapy”, and “venous thromboembolism”. A random-effects meta-analysis was conducted to obtain a pooled estimate of VTE prevalence in cancer patients undergoing chemotherapy. Results: A total of 102 eligible studies involving 30,671 patients (1773 with VTE, 28,898 without) were included in the meta-analysis. The pooled estimate of VTE prevalence was found to be 6%, ranging from 6% to 7% (ES 6%; 95% CI 6−7%; z = 18.53; p < 0.001). Conclusions: The estimated pooled prevalence rate of VTEs was 6% in cancer patients undergoing CRT, which was higher than the overall crude prevalence rate (5.78%). Comprehensive cancer care should consider stratified VTE risk assessment based on cancer phenotype, given that certain phenotypes of cancer such as bladder, gastric and ovarian posing particularly high risks of VTE.

Predictors of Early Thrombotic Events in Adult Patients with Acute Myeloid Leukemia: A Real-World Experience

Information regarding the incidence and the prognostic impact of thrombotic events (TE) in non-promyelocytic acute myeloid leukemia (AML) is sparse. Although several risk factors associated with an increased risk of TE development have been recognized, we still lack universally approved guidelines for identification and management of these complications. We retrospectively analyzed 300 consecutive patients with newly diagnosed AML. Reporting the incidence of venous TE (VTE) and arterial TE (ATE) was the primary endpoint. Secondarily, we evaluated baseline patient- and disease-related characteristics with a possible influence of VTE-occurrence probability. Finally, we evaluated the impact of TE on survival. Overall, the VTE incidence was 12.3% and ATE incidence was 2.3%. We identified three independent predictors associated with early-VTE: comorbidities (p = 0.006), platelets count >50 × 109/L (p = 0.006), and a previous history of VTE (p = 0.003). Assigning 1 point to each variable, we observed an overall cumulative incidence of VTE of 18.4% in the high-risk group (≥2 points) versus 6.4% in the low-risk group (0−1 point), log-rank = 0.002. Overall, ATE, but not VTE, was associated with poor prognosis (p < 0.001). In conclusion, TE incidence in AML patients is not negligible. We proposed an early-VTE risk score that could be useful for a proper management of VTE prophylaxis.

A prediction model for central venous catheter-related thrombosis in patients with newly-diagnosed acute myeloid leukemia: A derivation cohort analysis

BACKGROUND

Catheter-related thrombosis (CRT) is a common complication in cancer patients, that may lead to chemotherapy deferral, elevated risk for systemic infections and pulmonary embolism. This study aimed to assess CRT incidence and risk factors in newly-diagnosed acute myeloid leukemia (AML) patients and create predictive models potentially allowing to decrease CRT occurrence in this population.

METHODS

This retrospective single-center analysis included all AML patients treated at the Rambam Health Care Campus between 2006 and 2019. Patient clinical and laboratory data were collected to evaluate thrombosis occurrence and time from AML diagnosis to CRT development. Multivariate classification models were created using logistic regression (LR) and competing risk analyzes.

RESULTS

The final analysis included 632 newly-diagnosed AML patients (mean age 54 ± 15 years). CRT incidence was 10.1% [confidence interval (CI) 7.7-12.9%], median time from AML diagnosis to CRT was 12.5 days [interquartile range 6-30]. In an LR multivariate model, prior history of venous thromboembolism [adjusted odds ratio (AOR) 12.046, p < 0.0001], acute promyelocytic leukemia (APL) (AOR 2.824, p = 0.015), a high body mass index and initial platelet counts <100 × 10E9/L (AOR 1.059 and 0.546; p = 0.011 and 0.040, respectively) were significantly associated with high CRT risk. Analysis of 587 non-APL patients demonstrated comparable results, with CRT incidence of 9.3% (CI 7.0%-12.1%) and emergence of chronic obstructive pulmonary disease (COPD) as a novel significant co-factor (AOR 34.491, p = 0.004). In both models, the area under curve (AUC) was ≥70%.

CONCLUSIONS

Significant CRT risk factors defined using the created model could be used for identification of high-risk newly-diagnosed AML patients requiring CRT prophylaxis.