Effect of leukapheresis on blood coagulation in patients with hyperleukocytic acute myeloid leukemia

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.

Analysis of Risk Factors of Coagulation Dysfunction and Hemorrhage in Newly Diagnosed Hyperleukocytic Acute Myeloma Leukemia

Purpose

To explore whether and why abnormal coagulation function and hemorrhage can appear in patients with hyperleukocytic acute myeloid leukemia (HAML).

Method

We retrospectively reviewed the charts of 724 acute myeloid leukemia (AML) patients admitted with a white blood cell count of >100 × 10⁹/L between 2010 and 2019 in order to analyze the coagulation index of patients with HAML and explore the correlation of abnormal coagulation.

Result

Prothrombin time (PT) was extended in group HAML compared with group non-HAML. Respiratory failure, intracranial hemorrhage, and infection were more common in the HAML group. Among the 76 HAML patients, there were 33 patients who had ≥3 abnormal items of coagulation index, and 51.5% of them had level 2 hemorrhage which was more than level 0 hemorrhage, and the difference is statistically significant (P < 0.01). Similarly, we can discover that 40.9% of patients with 2 abnormal items had level 2 hemorrhage in contrast to 0 abnormal items. The use of hydroxyurea had a significant effect on PT and D-dimer (DD). Survival analysis by the Kaplan–Meier method showed that there were statistically significant differences in white blood cell (WBC) count＞200 × 10⁹//L and DD. Abnormal PT is associated with WBC count＞200 × 10⁹//L, and abnormal activated partial thromboplastin time (APTT) is associated with HLA-DR mutation. Infection and respiratory failure were independent influencing factors for the coagulation of patients.

Conclusion

DD had a marked effect on the survival rate. Infection and respiratory failure were independent influencing factors for the coagulation of patients.

Effectiveness and safety of leukapheresis in hyperleukocytic leukemias: a retrospective multicenter study

Leukapheresis is an effective adjuvant therapy for leukemia patients with hyperleukocytosis, but few studies have reported recent data with modern modalities and comparisons among different leukemia types. We conducted a retrospective study on leukapheresis among 420 patients with AML, ALL and CML in four local centers. WBC counts decreased significantly (p < 0.001) postleukapheresis in all three cohorts. Clearance efficiency was higher in acute leukemia patients than CML patients (p < 0.01). Concomitant leukocytoreduction drugs improved WBC reduction only in AML patients (p < 0.05). Leukocyte, hemoglobin and platelet levels preleukapheresis might affect the clearance efficiency in AML and/or ALL patients. Hematological toxicities were the major concerns, but most of them were mild, and only 11 patients died of all causes within one week postleukapheresis. In conclusion, leukapheresis can safely reduce the leukemic burden, especially for patients with acute leukemias.

Therapeutic Leukapheresis in Pediatric Leukemia: Utilization Trend and Early Outcomes in a US Nationwide Cohort

Leukapheresis (LA) in pediatric leukemia is performed for leukostasis, a life-threatening emergency in the setting of extremely increased blast cell counts. The authors aimed to assess the epidemiology of pediatric leukemia who received LA. The authors reviewed US nationally representative admission records of patients less than 20 years of age in the Kids' Inpatient Database for the years 2000, 2003, 2006, 2009, 2012, and 2016. Incidence of new leukemia cases who underwent LA were calculated for the years 2009, 2012, and 2016. Cox and logistic regression analyses were performed to ascertain the risk factors for adverse outcomes. There were 526 admissions for pediatric patients with acute lymphoblastic leukemia (ALL) (n=328), acute myeloid leukemia (AML) (n=124), or chronic myeloid leukemia (CML) (n=74) who underwent LA over the study period. The incidence of leukemia cases that required LA was lower in 2016 than in 2009 or 2012 (1.4%, 2.2%, and 2.7%, respectively; P=0.001). In-hospital mortality was higher in AML than ALL (hzard ratio, 3.2; 95% confidence interval, 1.1-9.1). None with CML died during admission. This first population-based study of LA in pediatric leukemia showed a decreased utilization of LA over recent years. The higher inpatient mortality in AML, as compared with ALL or CML, warrant further investigations.

The factors influencing clinical outcomes after leukapheresis in acute leukaemia

Leukapheresis is used for the mechanical removal of leukaemic cells in hyperleukocytosis. However, the effectiveness of leukapheresis remains unclear due to selection and confounding factors in the cohorts. We compared the effectiveness of leukapheresis among the subgroups according to either the 2016 World Health Organization classification or the number of cytogenetic abnormalities with a retrospective, single-centre study from January 2009 to December 2018. Acute myeloid leukaemia (AML, n = 212) and acute lymphoblastic leukaemia (ALL, n = 97) were included. The 30-day survival rates (95% confidence interval, 95% CI) for AML and ALL were 86.3% (81.6–90.9%) and 94.8% (90.3–99.2%), respectively. For AML, ‘primary AML with myelodysplasia-related changes’ and ‘AML with biallelic mutation of CEBPA’ showed better 30-day survival outcomes (P = 0.026) than the other subgroups. A higher platelet count after leukapheresis was associated with better 30-day survival in AML patients (P = 0.029). A decrease in blast percentage count after leukapheresis was associated with better 30-day survival in ALL patients (P = 0.034). Our study suggested that prophylactic platelet transfusion to raise the platelet count to 50 × 10⁹/L or greater might improve clinical outcome in AML patients undergoing leukapheresis.

Hyperleukocytosis and Leukostasis in Acute Myeloid Leukemia: Can a Better Understanding of the Underlying Molecular Pathophysiology Lead to Novel Treatments?

Up to 18% of patients with acute myeloid leukemia (AML) present with a white blood cell (WBC) count of greater than 100,000/µL, a condition that is frequently referred to as hyperleukocytosis. Hyperleukocytosis has been associated with an adverse prognosis and a higher incidence of life-threatening complications such as leukostasis, disseminated intravascular coagulation (DIC), and tumor lysis syndrome (TLS). The molecular processes underlying hyperleukocytosis have not been fully elucidated yet. However, the interactions between leukemic blasts and endothelial cells leading to leukostasis and DIC as well as the processes in the bone marrow microenvironment leading to the massive entry of leukemic blasts into the peripheral blood are becoming increasingly understood. Leukemic blasts interact with endothelial cells via cell adhesion molecules such as various members of the selectin family which are upregulated via inflammatory cytokines released by leukemic blasts. Besides their role in the development of leukostasis, cell adhesion molecules have also been implicated in leukemic stem cell survival and chemotherapy resistance and can be therapeutically targeted with specific inhibitors such as plerixafor or GMI-1271 (uproleselan). However, in the absence of approved targeted therapies supportive treatment with the uric acid lowering agents allopurinol and rasburicase as well as aggressive intravenous fluid hydration for the treatment and prophylaxis of TLS, transfusion of blood products for the management of DIC, and cytoreduction with intensive chemotherapy, leukapheresis, or hydroxyurea remain the mainstay of therapy for AML patients with hyperleukocytosis.

Pediatric acute lymphoblastic leukemia and leukapheresis: CT evidence of hemorrhagic complication

Leukapheresis has been used widely to quickly reduce white blood cell count (WBC) in patients with hyperleukocytosis. Despite its wide utilization, leukapheresis has risks of complication, which have not been thoroughly reported in pediatric patients. No report was found in English literatures about leukapheresis complications in children with acute lymphoblastic leukemia (ALL).

We reported a 4-year-old girl with ALL and hyperleukocytosis, with no sign of bleeding. After leukapheresis, WBC and platelet count decreased, and patient complained of headache. Neurological deficit developed quickly afterwards. Intracranial infection was suspected clinically. Contrast-enhanced head CT revealed multiple hyperdense lesions and diffuse cerebral oedema. The patient was subsequently diagnosed with multiple intraparenchymal hemorrhage, and leukapheresis was stopped.

Intracranial hyperdense lesion in leukemic patients has many differential diagnosis, such as infection, granulocytic sarcoma (chloroma), and hemorrhage. Lesion characteristics in CT could help point the diagnosis. History of leukapheresis should also raise suspicion of hemorrhage. This article discussed CT characteristics of multiple brain hemorrhage in pediatric ALL after leukapheresis and how to differentiate it with other common intracranial complications of leukemia.

Leukocytapheresis for patients with acute myeloid leukemia presenting with hyperleukocytosis and leukostasis: a contemporary appraisal of outcomes and benefits

Introduction: Hyperleukocytosis, defined as a total white blood cell count (WBC) >50 or more commonly >100 × 10⁹ cells/L, is a presenting feature of acute myeloid leukemia (AML) in about 6-20% of cases and is associated with a higher risk of tumor lysis syndrome (TLS), disseminated intravascular coagulation (DIC), clinical leukostasis with end organ damage, and mortality.Areas covered: In this review, authors discuss the implications of hyperleukocytosis in AML and the current understanding of cytoreductive strategies with a focus on the use of leukocytapheresis.Expert commentary: Efforts to rapidly reduce peripheral myeloblasts have included the use of leukocytapheresis. Early studies demonstrated feasibility in reducing peripheral WBC and blast counts as well as clinically relevant patient outcomes which prompted its common use for many years. However, more recent data have directly challenged the previously touted reports of reduced TLS and DIC incidence as well as survival benefit, even in patients with clinical leukostasis. The use of leukocytapheresis remains highly controversial with wide practice variations among physicians, institutions, and countries given the lack of high-quality data, risks associated with leukocytapheresis itself, associated high costs, resource utilization, and lack of evidence-based clinical guidelines.

A hospital based retrospective study of factors influencing therapeutic leukapheresis in patients presenting with hyperleukocytic leukaemia

Therapeutic leukapheresis is a rapid and effective method to reduce early mortality of patients with hyperleukocytic leukaemia (HLL). However, few studies on factors influencing the efficiency have been reported. In this study, 67 cases who underwent leukapheresis were retrospectively analysed and factors related to the collection efficiency of leukapheresis (CE_WBC) were also evaluated. Paired t test showed that there was a significant decrease in statistics of white blood cell (WBC) counts after apheresis. The results of two independent samples nonparametric test suggested that WBC counts, platelet (PLT) counts, haematocrit (HCT), hemoglobin (HGB), serum chlorine (Cl) and globulin (GLB) before leukapheresis correlated with the CE_WBC. Multiple linear regression analysis with background stepwise variable selection indicated that only WBC and HCT before leukapheresis had an influence on CE_WBC significantly. Kaplan-Meier analysis and Cox regression model indicated that lymphocyte (LY) and mean corpuscular hemoglobin (MCH) pre-apheresis as independent factors significantly affected the prognostic survival of patients with HLL. Moreover, platelets and red blood cell were contaminated in the product of leukapheresis. It is an urgent problem to be solved in order to realise higher efficacy and higher purity of WBC collection to improve the survival of patients with HLL through optimising instruments.

Complications and management of coagulation disorders in leukemia patients

Patients with leukemia are predisposed to various coagulation abnormalities. Thrombosis and bleeding continue to be a major cause of morbidity and mortality in leukemias. The pathophysiology of these disorders is unique, and not only the disease but also the treatment and other factors play a role. There has been an increase in the understanding of these disorders in leukemias. However, it is still difficult to predict when and which patients will have these complications. The evidence for the management of coagulation abnormalities in leukemias is still evolving and not as established as in solid malignancies. The management of these disorders is complex, and making clinical decisions is often challenging. In the era of specialization, where there are different hematologists looking after benign- and malignant-hematology patients, opinions of thrombosis experts are often sought by leukemia specialists. This review aims to bridge the gap in the knowledge of these disorders between these specialists.