Thrombosis in Myeloid Malignancies: From CHIP to AML

The development of myeloid malignancies is a multi-step process starting from pre-malignant stages. Large-scale studies on clonal hematopoiesis of indeterminate potential (CHIP) identified this condition as a risk factor for developing hematologic malignancies, in particular myelodysplastic syndromes (MDS) and acute myeloid leukemia (AML). In parallel, CHIP was found to confer an enhanced thrombotic risk, in particular for cardiovascular diseases. In a similar fashion, in recent years, alongside their life-threatening features, increasing attention has been drawn toward thrombotic complications in myeloid malignancies. Thus, the purpose of this review is to gather a growing body of evidence on incidence, pathogenesis and clinical impact of thrombosis in myeloid malignancies at every step of malignant progression, from CHIP to AML.

Improving the investigative approach to polycythaemia vera: a critical assessment of current evidence and vision for the future

Polycythaemia vera is a challenging disease to study given its low prevalence and prolonged time-to-event for important clinical endpoints such as thrombosis, progression, and mortality. Although researchers in this space often rise to meet these challenges, there is considerable room for improvement in the analysis of retrospective data, the development of risk-stratification tools, and the design of randomised controlled trials. In this Viewpoint, we review the evidence behind the contemporary approach to risk stratification and treatment of polycythaemia vera. Frameworks for using data more efficiently, constructing more nuanced prognostic models, and overcoming challenges in clinical trial design are discussed.

Partial Splenic Embolization Is a Safe and Effective Alternative in the Management of Portal Hypertension in Children

OBJECTIVE

There are multiple approaches to manage the clinical complications of portal hypertension (PHTN) to treat/prevent spontaneous hemorrhage by mitigating thrombocytopenia. No single approach is ideal for all patients given the heterogeneity of this population. Our goal was to determine whether partial splenic embolization (PSE) was safe and effective in the pediatric population.

METHODS

This is a retrospective review of our single-center experience for all patients ages 0 to 21 who underwent PSE between January 2010 and August 2017. The embolized splenic volume targeted was 60% to 70%.

RESULTS

Twenty-six patients underwent PSE due to thrombocytopenia and/or recurrent variceal bleeding. Patients ranged in age from 18 months to 20 years (mean 13.1 years). The median platelet count before PSE was 53.0 (×10/L). The platelet count improved after PSE with values >100,000 in 21 patients (80.8%). Children with prior esophageal varices showed improvement after PSE with only 9 (34.6%) requiring further endoscopic therapy. After PSE, patients developed transient abdominal pain, distention, fever, and perisplenic fluid collections. Serious complications such as splenic abscess, splenic rupture, bleeding, pancreatic infarction, opportunistic infection, or death were not observed. One patient experienced thrombotic complications after PSE and was later diagnosed with myelodysplastic syndrome.

CONCLUSIONS

PSE is a safe and effective alternative in the management of pediatric PHTN in select populations. PSE may be a favorable alternative to splenectomy and portal systemic shunting because it preserves functional spleen mass and avoids postprocedure accelerated liver disease or encephalopathy.

Hematological Malignancies and Arterial Thromboembolism

Established guidelines exist for prevention and treatment of venous thromboembolism in hematological malignancies, but none for arterial thromboembolism. However, arterial and venous thromboembolism share the same provoking features—including altered procoagulant factors and defective fibrinolytic system. The morbidity for arterial thromboembolism is increasing in hematological malignancies, with the advent of immunomodulatory and targeted therapy. However, survival rate for hematological malignancy is improving. Consequently, as patients with hematological malignancies live longer, comorbidities including diabetes, hypertension and dyslipidemia, may accentuate arterial thrombosis. Thus far, the scientific literature on prophylaxis and treatment for arterial thromboembolism in hematological malignancies is limited. This review highlights the pathogenesis, incidence and clinical features of arterial thromboembolism in hematological malignancies.

Erythropoiesis-stimulating agents and cardiovascular events in patients with myelodysplastic syndrome and multiple myeloma

Introduction

Erythropoiesis-stimulating agent (ESA) treatment has been associated with an increased risk of venous thromboembolism (VTE) in patients with solid tumors and with an increased risk of cardiovascular events in patients with chronic kidney disease. The ESA-related risk in patients with hematological neoplasms remains unclear. We, therefore, aimed to assess the ESA-related risk of VTE, myocardial infarction (MI), and stroke in patients with multiple myeloma (MM) and myelodysplastic syndrome (MDS).

Materials and methods

We conducted a population-based cohort study in Denmark, using medical databases to identify 2,114 MDS patients and 3,105 MM patients diagnosed in 2004–2013. Incidence rates per 1,000 person-years and hazard ratios (HRs) with 95% confidence intervals (CIs) for VTE, MI, and stroke associated with ESA treatment were computed. HRs were calculated in time-dependent Cox regression and adjusted for age, sex, MDS prognosis group, comorbidities, and treatments.

Results

Incidence rates per 1,000 person-years for VTE, MI, and stroke were 10.8, 8.2, and 16.0 in MDS patients, and 21.9, 10.2 and 9.9 in MM patients without ESA treatment, respectively. MDS patients with ESA treatment had a 1.6-fold increased risk of MI (HR 1.60 [95% CI 0.90–2.86]) and an almost twofold increased risk of stroke (HR 1.94 [95% CI 1.28–2.94]). Adjusted HR for VTE was 1.04 (95% CI 0.57–1.89) compared with MDS patients without ESAs. In MM patients with ESAs compared with patients without ESAs, HRs were 1.41 (95% CI 0.96–2.08) for VTE, 1.23 (95% CI 0.68–2.20) for MI, and 1.63 (95% CI 0.96–2.77) for stroke.

Conclusion

ESA use was associated with stroke in MDS patients. Among MM patients, ESA treatment was associated with a higher risk of all cardiovascular events, although all CIs included equivalence.

Risks of bleeding and thrombosis in intensive care unit patients with haematological malignancies

Background

Patients with malignant haematological disease and especially those who require intensive care have an increased risk of bleeding and thrombosis, but none of these data were obtained in ICU patients only. We assessed the incidence of bleeding and thrombotic complications, use of blood products and risk factors for bleeding in an adult population of ICU patients with haematological malignancies.

Methods

We screened all patients with acute leukaemia and myelodysplastic syndrome admitted to a university hospital ICU during 2008–2012. Bleeding in ICU was scored according to the WHO grading system, and risk factors were evaluated using unadjusted and adjusted analyses.

Results

In total, 116 of 129 ICU patients were included; their median length of stay was 7 (IQR 2–16) days. Of these, 66 patients (57%) had at least one bleeding episode in ICU; they bled for 3 (2–6) days and most often from lower and upper airways and upper GI tract. Thirty-nine (59%) of the 66 patients had severe or debilitating (WHO grade 3 or 4) bleeding. The median platelet count on the day of grade 3 or 4 bleeding was 23 × 10⁹ per litre (IQR 13–39). Nine patients (8%) died in ICU following a bleeding episode; five of these had intra-cerebral haemorrhage. Platelet count on admission was associated with subsequent bleeding (adjusted odds ratio 1.18 (95% CI 1.03–1.35) for every 10 × 10⁹ per litre drop in platelet count, p = 0.016). Eleven of the 116 patients (9%) developed a clinically significant thrombosis in ICU, which was the cause of death in four patients. The median platelet count was 20 × 10⁹ per litre (15–48) at the time of thrombosis. The patients received a median of 6 units of red blood cells, 1 unit of fresh frozen plasma and 8 units of platelet concentrates in ICU.

Conclusions

Severe and debilitating bleeding complications were frequent in our ICU patients with haematological malignancies, but thrombosis also occurred in spite of low platelet counts. Platelet count on ICU admission was associated with subsequent bleeding.

Electronic supplementary material

The online version of this article (10.1186/s13613-017-0341-y) contains supplementary material, which is available to authorized users.

Role of erythrocytes and platelets in the hypercoagulable status in polycythemia vera through phosphatidylserine exposure and microparticle generation

The development of thrombosis in polycythaemia vera (PV) involves multifactorial processes including pathological activation of blood cells. Release of microparticles (MPs) by activated cells in diseases is associated with thrombotic risk, but relatively few data are available in PV. The aim of the present study was to investigate the increase in MP release and exposure of phosphatidylserine (PS) on the outer membrane of MP-origin cells in patients with PV, and to analyse their procoagulant activity (PCA). PS-positive MPs and cells were detected by flow cytometry, while PCA was assessed with clotting time and purified coagulation complex assays. We found that PV patients had elevated circulating lactadherin+ MPs, which mostly originating from erythrocytes, platelets, granulocytes, and endothelial cells, as well as increased PS exposing erythrocytes/platelets as compared to secondary polycythaemia patients or healthy controls. These PS-bearing MPs and cells were highly procoagulant. Moreover, lactadherin competed factor V and VIII to PS and inhibited about 90% of the detected PCA in a dose-response manner while anti-TF antibody did no significant inhibition. Treatment with hydroxyurea is associated with a decrease in PS exposure and lactadherin+ MP release of erythrocytes/platelets. Our data demonstrate that PV patients are characterised by increased circulating procoagulant MPs and PS exposing erythrocytes/platelets, which could contribute to the hypercoagulable state in these patients.

Eryptosis in health and disease: A paradigm shift towards understanding the (patho)physiological implications of programmed cell death of erythrocytes

During the course of their natural ageing and upon injury, anucleate erythrocytes can undergo an unconventional apoptosis-like cell death, termed eryptosis. Eryptotic erythrocytes display a plethora of morphological alterations including volume reduction, membrane blebbing and breakdown of the membrane phospholipid asymmetry resulting in phosphatidylserine externalization which, in turn, mediates their phagocytic recognition and clearance from the circulation. Overall, the eryptosis machinery is tightly orchestrated by a wide array of endogenous mediators, ion channels, membrane receptors, and a host of intracellular signaling proteins. Enhanced eryptosis shortens the lifespan of circulating erythrocytes and confers a procoagulant phenotype; this phenomenon has been tangibly implicated in the pathogenesis of anemia, deranged microcirculation, and increased prothrombotic risk associated with a multitude of clinical conditions. Herein, we reviewed the molecular mechanisms dictating eryptosis and erythrophagocytosis and critically analyzed the current evidence leading to the pathophysiological ramifications of eryptotic cell death in the context of human disease.

Superior mesenteric vein thrombosis as an early presentation of myelodysplastic syndrome: a case report

Mesenteric venous thrombosis (MVT) is a serious condition due to its potential association with mesenteric ischemia and infarction of the small bowel. Symptoms of MVT are often vague, making accurate diagnosis and sufficient treatment difficult. However, increased awareness and new imaging modalities for this condition have improved outcomes for patients with MVT. Treatment includes anticoagulation, transcatheter therapy, and surgery. In the present report, we describe the case study of a 62-year-old woman with a presenting diagnosis of superior MVT, who was finally diagnosed with myelodysplastic syndrome. The superior MVT spontaneously dissolved after the patient underwent 6 months of systemic anticoagulation therapy. Invasive surgery or bowel resection was not required.

A lower intensity of treatment may underlie the increased risk of thrombosis in young patients with masked polycythaemia vera

In patients who do not meet the World Health Organization (WHO) criteria for overt polycythaemia vera (PV), a diagnosis of masked PV (mPV) can be determined. A fraction of mPV patients may display thrombocytosis, thus mimicking essential thrombocythaemia (ET). No previous studies have examined clinical outcomes of mPV among young JAK2-mutated patients. We analysed a retrospective cohort of 538 JAK2-mutated patients younger than 40 years, after a re-assessment of the diagnosis according to the haemoglobin threshold for mPV. In this cohort of patients, 97 (18%) met the WHO criteria for PV, 66 patients (12%) were classified as mPV and 375 (70%) as JAK2-mutated ET. Surprisingly, a significant difference in the incidence of thrombosis was found when comparing mPV versus overt PV patients (P = 0·04). In multivariate analysis, the only factor accounting for the difference in the risk of thrombosis was the less frequent use of phlebotomies and cytoreduction in mPV patients compared to those with overt PV. Thus, we emphasize the need for the identification of mPV in young JAK2-mutated patients in order to optimize their treatments.

Renal biopsy cases in myeloproliferative neoplasms (MPN)

We performed renal biopsy in three cases complicated by myeloproliferative neoplasms (MPN). Although several cases of glomerulonephritis associated with MPN have been reported, the etiologies of the renal disorders were not established (Plomley et al., Aust NZ J Med, 13:125–129, 1983; Sharma et al., Nephron, 69:361, 1995; Kanauchi et al., Intern Med, 33:36–40, 1994; Kasuno et al., Nephrol Dial Transplant, 12:212–215, 1997; Au et al., Am J Kid Dis, 34:889–893, 1999; Kosch et al., Nephrol Dial Transplant, 15:1710–1711, 2000; Oymak et al., Nephron, 86:346–347, 2000; Chun et al., Am J Nephrol, 20:344–346, 2000; Chung et al., Am J Nephrol, 22:397–401, 2002; Asaba et al., Clin Exp Nephrol, 7:296–300, 2003; Haraguchi et al., Clin Exp Nephrol, 10:74–77, 2006; Saigusa et al., J Nephrol, 19:656–658, 2006; Okuyama et al., Clin Nephrol, 6:412–415, 2007; Nishi et al., Clin Nephrol, 5:393–398, 2010; Ulusoy et al., Intern Med, 49:2477, 2010). A review of previous reports of renal biopsy cases with MPN in the English literature suggested that circulation control is important for the treatment of renal disorders that mimic glomerulonephritis in MPN.