Emerging risk stratification approaches to cancer-associated thrombosis: risk factors, biomarkers and a risk score

Association of pathologic factors with postoperative venous thromboembolism after gastrointestinal cancer surgery

BACKGROUND

Venous thromboembolism (VTE) chemoprophylaxis is the standard of care after gastrointestinal (GI) cancer surgery; however, variation in risk based on pathologic factors (eg, stage and histology) is unclear. This study aimed to evaluate the association of pathologic factors with VTE after GI cancer surgery.

METHODS

The American College of Surgeons National Surgical Quality Improvement Program procedure targeted datasets were queried for patients who underwent colorectal, pancreatic, primary hepatic, and esophageal cancer surgery between 2017 and 2020. Disease-specific and pathologic factors associated with postoperative VTE were evaluated using multivariable logistic regression.

RESULTS

Among 70,934 patients who underwent GI cancer surgery, the incidence rates of 30-day postoperative VTE were 3.3% for pancreatic cancer, 3.2% for esophageal cancer, 2.7% for primary hepatic, and 1.3% for colorectal cancer. T stage was associated with VTE for colorectal cancer (T4 vs T1; odds ratio [OR], 1.79; 95% CI, 1.24-2.60), pancreatic cancer (all T stages vs T1; P < .05), and primary hepatic cancer (T4 vs T1; OR, 2.80; 95% CI, 1.55-5.08). N stage was associated with VTE for colorectal cancer (N2 vs N0; OR, 1.33; 95% CI, 1.04-1.68) and pancreatic cancer (N2 vs N0; OR, 1.36; 95% CI, 1.03-1.81). M stage was associated with VTE for colorectal cancer (OR, 1.47; 95% CI, 1.17-1.85) and esophageal cancer (OR, 2.54; 95% CI, 1.24-5.19). Histologic subtype was not associated with VTE, except for pancreatic neuroendocrine tumors vs adenocarcinoma (OR, 1.34; 95% CI, 1.03-1.74).

CONCLUSION

Pathologic factors were associated with higher 30-day VTE risk after GI cancer surgery. Acknowledging the association of pathologic factors on VTE is an important first step to considering a more tailored approach to chemoprophylaxis.

Cancer-Associated Thrombosis: Pathophysiology, Laboratory Assessment, and Current Guidelines

Dysregulated hemostasis in cancer patients is associated with various clinical conditions, from thromboembolic complications to disseminated intravascular coagulation. Despite the well-established association between cancer and thromboembolic complications, the mechanisms involved are not completely elucidated. There are several predisposing factors in cancer for increased thrombus generation, such as immobilization and chemotherapy. The term cancer-associated thrombosis (CAT) has been introduced to describe the close bidirectional relationship between cancer and thromboembolic events. Conventional coagulation tests (PT/aPTT) are more accurate in detecting a hypocoagulable rather than a hypercoagulable state; thus, their contribution to CAT management is limited. Traditionally, D-dimer levels have been the most common laboratory study for the evaluation of thrombotic risk. However, D-dimer levels only display a snapshot of the coagulation cascade, and they cannot provide a dynamic evaluation of evolving clot formation. Non-conventional assays, such as viscoelastic methods and microparticle formation are promising tools for the identification of patients at risk for developing CAT. Recent guidelines from the American Society of Clinical Oncology counsel against the estimation of thrombotic risk through a single test and recommend the use of scoring systems that take into account several risk factors. The present review outlines the current insights into the pathophysiological mechanisms of CAT and provides a comprehensive review of the latest advances in the laboratory assessment of CAT and the recent guidelines for the management of patients at risk for developing thromboembolic complications.

Late venous thromboembolism in survivors of adolescent and young adult cancer: A population-based study in California

INTRODUCTION

Venous thromboembolism (VTE), a common complication in cancer patients, occurs more often during the initial phase of treatment. However, information on VTE beyond the first two years after diagnosis ('late VTE') is scarce, particularly in young survivors.

METHODS

We examined the risk of, and factors associated with, late VTE among adolescents and young adults (AYA, 15-39 years) diagnosed with cancer (2006-2018) who survived ≥2 years. Data were obtained from the California Cancer Registry linked to hospitalization, emergency department and ambulatory surgery data. We used non-parametric models and Cox proportional hazard regression for analyses.

RESULTS

Among 59,343 survivors, the 10-year cumulative incidence of VTE was 1.93 % (CI 1.80-2.07). The hazard of VTE was higher among those who had active cancer, including progression from lower stages to metastatic disease (Hazard Ratio (HR) = 10.41, 95 % confidence interval (CI): 8.86-12.22), second primary cancer (HR = 2.58, CI:2.01-3.31), or metastatic disease at diagnosis (HR = 2.38, CI:1.84-3.09). The hazard of late VTE was increased among survivors who underwent hematopoietic cell transplantation, those who received radiotherapy, had a VTE history, public insurance (vs private) or non-Hispanic Black/African American race/ethnicity (vs non-Hispanic White). Patients with leukemias, lymphomas, sarcoma, melanoma, colorectal, breast, and cervical cancers had a higher VTE risk than those with thyroid cancer.

CONCLUSIONS

VTE risk remained elevated ≥2 years following cancer diagnosis in AYA survivors. Active cancer is a significant risk factor for VTE. Future studies might determine if late VTE should prompt evaluation for recurrence or second malignancy, if not already known.

Adult breast, lung, pancreatic, upper and lower gastrointestinal cancer patients with hospitalized venous thromboembolism in the national French hospital discharge database

BACKGROUND

Venous thromboembolism (VTE) and cancer are strongly associated. In France, evidence on patients with pancreatic, upper GI [gastrointestinal], lower GI, lung, or breast cancer-associated VTE and their hospital management is limited. The aims of this study were to provide data on the number of hospitalized VTE events among cancer patients, the patients' characteristics, and their hospital management to estimate the burden of disease and the hospital burden of cancer-related VTE and to provide guidance on research.

METHODS

This longitudinal, observational, and retrospective study was based on the comprehensive hospital discharge database (PMSI). Adult patients (≥ 18 years old) hospitalized with a cancer of interest in 2016 and hospitalized (within 2 years with VTE (captured a as a principal, related, or significant associated diagnosis) were included in the study.

RESULTS

We identified 340,946 cancer patients, of which 7.2% (24,433 patients) were hospitalized with VTE. The proportions of hospitalized VTE were 14.6% (3,237) for patients with pancreatic cancer, 11.2% (8,339) for lung cancer, 9.9% (2,232) for upper GI cancer, 6.7% (7,011) for lower GI cancer, and 3.1% (3,614) for breast cancer. Around two thirds of cancer patients with a hospitalized VTE had active cancer (with metastases and/or receiving chemotherapy during the six months prior to the index date): from 62% of patients with pancreatic cancer to 72% with breast cancer. Around a third of patients were admitted to the hospital through the emergency room, up to 3% of patients stayed in an intensive care unit. The average length of stay ranged from 10 (breast cancer) to 15 days (upper GI cancer). Nine (lower GI cancer) to 18% (pancreatic cancer) of patients died during the VTE hospital stay.

CONCLUSIONS

The burden of cancer-associated VTE is substantial, both in terms of the number of patients affected and in the hospital use. These findings offer guidance on future research on VTE prophylaxis in a very high-risk population, particularly in patients with active cancer.

Catheter Directed Thrombectomy and Other Deep Venous Interventions in Cancer Patients

Treating cancer patients with deep venous thrombosis/venous thromboembolism (DVT/VTE) can be challenging as patients are frequently unable to receive the standard therapy of anticoagulation due to the increased risk of bleeding complications seen in this population. Similarly, the hesitation of interventionalists to use thrombolytic agents due to bleeding risks limits percutaneous intervention options as well. Further, outcome data and guidelines do not exist for oncologic patients and often treatment is tailored to patient-specific factors after multidisciplinary discussion. This article reviews specific factors to consider when planning percutaneous treatment of cancer patients with DVT/VTE, focusing on the iliocaval system.

Perioperative Anticoagulation in Patients with Cancer

PURPOSE OF REVIEW

There is a paucity of evidence for managing perioperative anticoagulation in patients with cancer. This review aims to provide clinicians who provide care for patients with cancer an overview of the available information and strategies needed to provide optimal care in a perioperative setting.

RECENT FINDINGS

There is new evidence available around the management of perioperative anticoagulation in patients with cancer. The new literature and guidance were analyzed and summarized in this review. Management of perioperative anticoagulation in individuals with cancer is a challenging clinical dilemma. The approach to managing anticoagulation requires clinicians to review both disease and treatment specific patient factors that can contribute to both thrombotic and bleed risks. A thorough patient-specific assessment is essential in ensuring patients with cancer receive appropriate care in the perioperative setting.

The emerging role of neutrophil extracellular traps in cancer: from lab to ward

Neutrophil extracellular traps (NETs) are web-like structures derived from neutrophils, which typically consist of DNA, released from the nucleus or mitochondria, and decorated with histones and granule proteins. They are well known as an important structure in innate immunity to eliminate pathogenic bacteria, similar to neutrophils. Initially, NETs are reported to take part in the progression of inflammatory diseases; now, they have also been implicated in the progression of sterile inflammation such as autoimmune disease, diabetes, and cancer. In this review, we will describe the recent studies which have investigated the role of NETs in the development of cancer, especially metastasis. We also prescribe the strategies for targeting NETs in the multiple cancer types, which suggest that NETs are a promising treatment for cancer patients.

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.

Preoperative oncologic therapy and the prolonged risk of venous thromboembolism in resectable pancreatic cancer

BACKGROUND

Pancreatic cancer is one of the most prothrombotic cancers. Among patients receiving preoperative chemotherapy followed by surgery, chemotherapy and surgery represent a compound risk for venous thromboembolism (VTE), rendering the postoperative time a period of interest. We aimed to analyze whether preoperative oncologic therapy increases the risk for VTE after surgery and identify which characteristics associate with VTE.

METHODS

We first identified patients surgically treated for pancreatic cancer at Helsinki University Hospital between 2000 and 2017, collecting the following data: gender, age at surgery, preoperative medication, body mass index (BMI), preoperative chemo(radio)therapy, tumor size, positive node ratio, perineural and perivascular invasion, tumor grade, surgical technique, postoperative anticoagulation, adjuvant therapy, time of VTE, time of local disease recurrence, time of distant metastasis, and time of death. With a follow-up period of at least 2 years or until death, we compared a total of 93 preoperative oncologic therapy and 291 upfront surgery patients (n = 384, median age 66.5 years).

RESULTS

Preoperative oncologic therapy increased the risk for thrombosis after surgery (hazard ratio [HR] 1.61; 95% confidence interval [CI] 1.03-2.53). The VTE incidence rate remained high for up to 2 years after surgery. BMI ≥30 kg/m2 , prior anticoagulation, and disease recurrence (p < 0.05, respectively) associated with VTE. VTE is also associated with shorter overall survival (HR 3.25; 95% CI 2.36-4.44). In 71.6% (95% CI 60.5-81.1) of patients, VTE was diagnosed after disease recurrence.

CONCLUSIONS

Preoperative oncologic therapy represents an independent risk factor for VTE, not only during the immediate postoperative period but up to 2 years after surgery. VTE is associated with obesity, prior anticoagulation, and disease recurrence and diminishes overall survival.

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

The frequency of thrombosis in AML has been evaluated only in a few studies and no validated predictive model is currently available. Recently, DIC score was shown to identify patients at higher thrombotic risk. We aimed to evaluate the frequency of thromboembolism in AML patients treated with intensive chemotherapy and to assess the ability of genetic and clinical factors to predict the thrombotic risk. We performed a retrospective observational study including 222 newly diagnosed adult AML (210) and high-risk MDS (12), treated with intensive chemotherapy between January 2013 and February 2020. With a median follow-up of 44 months, we observed 50 thrombotic events (90% were venous, VTE). The prevalence of thrombosis was 22.1% and the 6-months cumulative incidence of thrombosis was 10%. The median time to thrombosis was 84 days and 52% of the events occurred within 100 days from AML diagnosis. Khorana and DIC score failed to stratify patients according to their thrombotic risk. Only history of a thrombotic event (p = 0.043), particularly VTE (p = 0.0053), platelet count above 100 × 10⁹/L at diagnosis (p = 0.036) and active smoking (p = 0.025) significantly and independently increased the risk of thrombosis, the latter particularly of arterial events. AML genetic profile did not affect thrombosis occurrence. Results were confirmed considering only thromboses occurring within day 100 from diagnosis. DIC score at diagnosis, but not thrombosis, was independently associated with reduced survival (p = 0.004). Previous VTE, platelet count above 100 × 10⁹/L and active smoking were the only factors associate with increased thrombotic risk in AML patients treated intensively, but further studies are needed to validate these results.

Current Recommendations for the Management of Cancer-Associated Venous Thromboembolism

Cancer-associated thrombosis (CAT) is a major cause of death in oncological patients. The mechanisms of thrombogenesis in cancer patients are not fully established, and it seems to be multifactorial in origin. Also, several risk factors for venous thromboembolism (VTE) are present in these patients such as tumor site, stage, histology of cancer, chemotherapy, surgery, and immobilization. Anticoagulant treatment in CAT is challenging because of high bleeding risk during treatment and recurrence of VTE. Current major guidelines recommend low molecular weight heparins (LMWHs) for early and long-term treatment of VTE in cancer patients. In the past years, direct oral anticoagulants (DOACs) are recommended as potential treatment option for VTE and have recently been proposed as a new option for treating CAT. This manuscript will give a short overview of risk factors involved in the development of CAT and a summary on the recent recommendations and guidelines for treatment of VTE in patients with malignancies, discussing also some special clinical situations (e.g. renal impairment, catheter-related thrombosis, and thrombocytopenia).

Venous and Arterial Thromboembolism in Patients With Cancer: JACC: CardioOncology State-of-the-Art Review

Venous thromboembolism (VTE), including deep vein thrombosis and pulmonary embolism, represents a major cause of morbidity and mortality in patients with cancer. Arterial thromboembolism, including myocardial infarction and stroke, is also prevalent. Risk differs in subgroups, with higher rates observed in specific cancers including pancreas, stomach, and multiple myeloma. Thromboprophylaxis is recommended for most patients with active cancer hospitalized for medical illnesses and after major cancer surgery. Outpatient thromboprophylaxis is not routinely recommended, but emerging data suggest that a high-risk population that benefits from pharmacological thromboprophylaxis can be identified using a validated risk tool. Direct oral anticoagulants are emerging as the preferred new option for the treatment of cancer-associated VTE, although low-molecular-weight heparin remains a standard for patients at high bleeding risk. Management of VTE beyond the first 6 months and challenging clinical situations including intracranial metastases and thrombocytopenia require careful management in balancing the benefits and risks of anticoagulation and remain major knowledge gaps in evidence.

Cancer-Associated Venous Thromboembolism in Ambulatory Solid Organ Malignancy Patients: Experience from a Cancer Research Institute

Cancer-associated deep venous thrombosis (DVT) and venous thromboembolism (VTE) are exceedingly common in patients with cancer. One-fifth of DVT events occur in patients with cancer and it is the second leading cause of death in patients with cancer after cancer itself. Data on DVT in cancer patients on medical therapy, especially from Indian experiences, are sparse. Here, we present our experience in ambulatory patients with solid organ cancer. The purpose of the study was to study the incidence of DVT in cancer patients on medical therapy and to analyze probable DVT risk factors. This study was a hospital-based single-arm retrospective collection and analysis of hospital records from patients receiving medical therapy on an outpatient and short-stay basis. From January 2016 to February 2017, adult solid organ cancer patients attending the medical oncology outpatient department (OPD), receiving active anticancer treatment, either oral or injectable, were included. The data was retrieved from the medical records department and the department of radiology. Descriptive statistics were used to analyze the data. Twenty-nine out of 1190 patients were documented to have developed DVT during the study period. The incidence of DVT in the outpatient settings was 2.4%, and DVT associated with venous access device in situ was seen in 4.05% (20/493) of the patients. Gynecological, breast, and hepatobiliary malignancies comprised most of the cases. Cancer patients are clearly at increased risk for DVT, but this risk is highly variable. It differs between subgroups of cancer patients. Five points Khorana risk model can predict risk for DVT in the ambulatory cancer patients receiving chemotherapy; however, the routine use of thromboprophylaxis in all cancer patients is not recommended. High-risk patients especially those with venous access devices need careful evaluation and counseling for prompt reporting and recognition of venous thrombosis.

Coagulopathy and Venous Thromboembolic Events Following Cytoreductive Surgery and Hyperthermic Intraperitoneal Chemotherapy

Background

Coagulopathy after cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) is recognized but few details have been studied.

Objectives

The aim of this study was to investigate changes in coagulation biomarkers and their predictive ability for venous thromboembolism (VTE).

Methods

Patients undergoing CRS and HIPEC at Uppsala University Hospital, Sweden, from 2004 to 2014 were included in a prospective study of coagulation biomarkers. Prothrombin time international normalized ratio (PT-INR), activated partial thromboplastin time (APTT), fibrinogen, antithrombin, D-dimer, and platelets were sampled on postoperative days 1, 2, 5, and 10. Logistic regression analysis was used to evaluate predictive capacity for coagulation-related complications.

Results

Overall, 380 patients were included (214 females, mean age 56 years); 38 patients had a history of thromboembolism and 57 were active smokers. Mean perioperative blood loss was 1228 mL and 231 (61%) received perioperative blood transfusions. PT-INR and APTT were elevated directly after surgery but returned to normal levels on postoperative day 5. Conversely, fibrinogen, platelet count, D-dimer, and antithrombin increased by postoperative day 5 and continued to increase up to day 10. There were 23 radiologically verified cases of VTE within 6 months. The multivariate analysis identified a completeness of cytoreduction score of 2–3 (p = 0.047) and day 2 D-dimer (p = 0.0082) as independent risk factors for postoperative VTE.

Conclusion

Significant postoperative changes in coagulation biomarkers occur with dynamic changes over 10 days postoperatively. The incidence of symptomatic VTE was low. Residual tumor at completion of surgery and elevated D-dimer on day 2 were independent risk factors for postoperative VTE.

Targeting Thymidine Phosphorylase With Tipiracil Hydrochloride Attenuates Thrombosis Without Increasing Risk of Bleeding in Mice

OBJECTIVE

Current antiplatelet medications increase the risk of bleeding, which leads to a clear clinical need in developing novel mechanism-based antiplatelet drugs. TYMP (Thymidine phosphorylase), a cytoplasm protein that is highly expressed in platelets, facilitates multiple agonist-induced platelet activation, and enhances thrombosis. Tipiracil hydrochloride (TPI), a selective TYMP inhibitor, has been approved by the Food and Drug Administration for clinical use. We tested the hypothesis that TPI is a safe antithrombotic medication. Approach and Results: By coexpression of TYMP and Lyn, GST (glutathione S-transferase) tagged Lyn-SH3 domain or Lyn-SH2 domain, we showed the direct evidence that TYMP binds to Lyn through both SH3 and SH2 domains, and TPI diminished the binding. TYMP deficiency significantly inhibits thrombosis in vivo in both sexes. Pretreatment of platelets with TPI rapidly inhibited collagen- and ADP-induced platelet aggregation. Under either normal or hyperlipidemic conditions, treating wild-type mice with TPI via intraperitoneal injection, intravenous injection, or gavage feeding dramatically inhibited thrombosis without inducing significant bleeding. Even at high doses, TPI has a lower bleeding side effect compared with aspirin and clopidogrel. Intravenous delivery of TPI alone or combined with tissue plasminogen activator dramatically inhibited thrombosis. Dual administration of a very low dose of aspirin and TPI, which had no antithrombotic effects when used alone, significantly inhibited thrombosis without disturbing hemostasis.

CONCLUSIONS

This study demonstrated that inhibition of TYMP, a cytoplasmic protein, attenuated multiple signaling pathways that mediate platelet activation, aggregation, and thrombosis. TPI can be used as a novel antithrombotic medication without the increase in risk of bleeding.

The role of balloon pulmonary angioplasty and pulmonary endarterectomy: Is chronic thromboembolic pulmonary hypertension still a life-threatening disease?

BACKGROUND

The management of non-operable chronic thromboembolic pulmonary hypertension (CTEPH) has evolved with the availability of balloon pulmonary angioplasty (BPA) and pulmonary vasodilators. We launched the BPA program in 2011. The aim was to analyze the survival and treatment efficacy of our CTEPH treatment program in the modern management era.

METHODS AND RESULTS

We retrospectively reviewed data from 143 consecutive CTEPH patients diagnosed from January 2011 (i.e. after the availability of BPA) to December 2019. Of forty-one patients who underwent pulmonary endarterectomy (PEA), 25 underwent additional BPA (Combination group) and the others were treated with only PEA (PEA group). Ninety patients underwent BPA (BPA group). The remaining 12 patients did not undergo any interventional treatments. The 1- and 5-year survival rates of operated patients (n = 41) were 97.4% and 90.0%, compared to 96.9% and 86.9% in not-operated patients (n = 102), respectively (p = 0.579). There was no mortality in the Combination group. Mean pulmonary artery pressure after treatments in the PEA only, Combination, and BPA only groups was 20.5 ± 6.7, 17.9 ± 4.9, and 20.7 ± 4.6 mmHg, respectively (p = 0.067, one-way ANOVA). Percent decrease of pulmonary vascular resistance in each treatment groups was -73.7 ± 11.3%, -74.3 ± 11.8%, and - 54.9 ± 22.5%, respectively (p < 0.01, one-way ANOVA).

CONCLUSION

There was no significant difference in long-term survival between operated and not-operated CTEPH. Moreover, the Combination approach might have the potential to introduce notable improvements in the prognosis of CTEPH. BPA and PEA appear to be mutually complementary therapies in the modern management era.

Cerebral infarction after left upper lung lobectomy with central vascular ligation

Background

Thrombus of the pulmonary vein (PV) stump is reportedly more frequent after left upper lobectomy than after other lobectomies, risking postoperative cerebral infarction (PCI). We have performed central vascular ligation before vascular dissection to improve the safety of surgical stapling. The effects of central vascular ligation in terms of PV stump thrombus and PCI are uncertain.

Methods

This study retrospectively reviewed the records of patients who underwent left upper lobectomy at a single center (Hokkaido Cancer Center, Sapporo, Japan) between November 1, 2008 and July 31, 2018. Relationships between PCI, PV stump thrombus and background characteristics were investigated and analyzed.

Results

All 208 cases of left upper lobectomy underwent central vascular ligation of the PV during this study. PCI occurred in 8 of the 208 patients. PV stump thrombus was detected in 14 of the 132 patients. In comparison with no-PCI cases, PCI cases showed significantly higher rates of comorbidity with cardiovascular disease (P=0.02), double cancer within 5 years (P=0.04), intraoperative hyperthermic chemotherapy (P=0.02), postoperative intrapleural inflammation (P=0.02) and postoperative PV stump thrombus (P=0.04). Presence of both comorbid cardiovascular disease (odds ratio, 18.4) and intraoperative hyperthermic chemotherapy (odds ratio, 30.4) was associated with higher risk of PV stump thrombus than presence of none of these factors. Cerebral infarction within 30 days postoperatively was seen in only 2 of the 208 cases (1.0%).

Conclusions

Central ligation of the PV may prevent postoperative early cerebral infarction. Further study of the effectiveness of this method for preventing PV stump thrombus is needed.

[Treatment and secondary prevention of venous thromboembolism in cancer patients]

Oncological patients are a high-risk group for venous thromboembolic complications. These complications significantly impair the outcome of antitumor treatment and take a leading place in the structure of mortality. Treatment of venous thromboembolic complications in oncological patients is a serious challenge. When selecting an anticoagulant, the physician should consider its efficacy and safety and possible drug interactions. Based on results of multiple studies presented in this article, physicians will be able to choose an optimum therapeutic tactics and secondary prevention of thromboembolic complications for this group of patients.

Venous thromboembolic complications in lymphoma patients

Lymphomas represent a heterogeneous group of malignant hematological diseases with high risk for development of venous thromboembolic complications (VTE). Consequently, VTE significantly impacts morbidity and mortality in these patients. Another concern is the financial burden of the healthcare system caused by diagnostic and therapeutic procedures of cancer-associated thrombosis (CAT). The complex biology of lymphoma, in conjunction with patient and treatment related risk factors for the development of VTE, results in a procoagulant hemostatic dysregulation. Considering the incidence of VTE in patients with lymphoma, there is an emerging demand for both reliable risks assessment model (RAM) for prediction of VTE, as well as for effective VTE prophylaxis and treatment. The clinical course of patients with malignant diseases is accompanied by a wide range of potential treatment complications, making the task of prevention and treatment of VTE even more challenging. In recent years, great progress has been achieved in understanding the pathophysiological mechanisms of thrombotic complications, while the significant number of randomized controlled trials (RCT) have provided standards of prophylaxis and treatment of VTE complications in patients with malignancy. In comparison to previous recommendations and guidelines for CAT, the use of direct oral anticoagulants (DOAC) has been gradually approaching low molecular weight heparins (LMWH) in terms of efficacy and safety profile in these indications. This systematic review is focused on the latest pathophysiological advances, risk factors assessment, prophylactic and therapeutic recommendations and guidelines concerning VTE in patients with lymphoma.

Prospective Registry of Rivaroxaban Management of Cancer-Associated Venous Throboembolism (PRIMECAST) Study

Background: The incidence of thromboembolism in patients with cancer is approximately 11%, and the risk of thrombosis in patients with malignant tumors is 6-fold higher than that in healthy persons. Thrombosis not only disrupts the treatment of cancer but also induces deterioration of quality of life (QOL). Knowledge about thrombus treatment is limited, and evidence is scarce. Clarification of the status and safety of venous thromboembolism (VTE) treatment in patients with cancer will contribute to active intervention and improvement of prognosis and QOL. In this study, the therapeutic effects of a non-vitamin K antagonist oral anticoagulant for VTE and the prognosis of cancer after treatment will be examined to establish a therapeutic method for VTE in patients with cancer.

Methods and Results: A multicenter, non-interventional, observational study will be conducted in patients with cancer who developed VTE and underwent anticoagulant therapy with rivaroxaban (group A) or warfarin (group B) for 24 weeks. The primary endpoint will be the recurrence/aggravation of symptomatic VTE or occurrence/aggravation of deep vein thrombosis. Registration of 500 patients is needed in order to calculate the 95% confidence interval of the event rate at ±1% precision.

Conclusions: The investigation period will run from January 2019 to December 2023 with ongoing selection of patients. Trial registration: no. 5-18-32 (approved 1 August 2018).

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.

Cancer-Associated Thrombosis: An Overview of Mechanisms, Risk Factors, and Treatment

Cancer-associated thrombosis is a major cause of mortality in cancer patients, the most common type being venous thromboembolism (VTE). Several risk factors for developing VTE also coexist with cancer patients, such as chemotherapy and immobilisation, contributing to the increased risk cancer patients have of developing VTE compared with non-cancer patients. Cancer cells are capable of activating the coagulation cascade and other prothrombotic properties of host cells, and many anticancer treatments themselves are being described as additional mechanisms for promoting VTE. This review will give an overview of the main thrombotic complications in cancer patients and outline the risk factors for cancer patients developing cancer-associated thrombosis, focusing on VTE as it is the most common complication observed in cancer patients. The multiple mechanisms involved in cancer-associated thrombosis, including the role of anticancer drugs, and a brief outline of the current treatment for cancer-associated thrombosis will also be discussed.

Venous Thromboembolism in Patients with Sarcoma: A Retrospective Study

BACKGROUND

Little has been published about the association of venous thromboembolism (VTE) and sarcoma. In this study, we sought to identify clinical features of patients with sarcoma presenting at least one VTE episode.

METHODS

Our study was a retrospective case-control study of a single-institution database with univariate and multivariate analysis using chi-square and Student's t test. A p value less than .05 was considered significant.

RESULTS

The overall incidence of VTE in patients with sarcoma was 7.9%. Predictive factors identified by multivariate analysis were metastatic disease and administration of chemotherapy. It was not statistically possible to correlate the risk of VTE with specific sarcoma subtypes, but observations suggested malignant peripheral nerve sheath tumor, osteosarcoma, and liposarcoma as having the highest propension.

CONCLUSION

VTE is not infrequent in patients with sarcoma. Adoption of common guidelines for cancer-associated thrombosis is recommended.

Cancer patients' experiences of living with venous thromboembolism: A systematic review and qualitative thematic synthesis

BACKGROUND

Cancer-associated thrombosis is common. Recommended treatment is daily injected low-molecular-weight heparin for 6 months. Most studies focus on prophylaxis and treatment; few have explored the patients' experience.

AIMS

To identify and synthesise the available literature concerning patients' experience of cancer-associated thrombosis.

DESIGN

Systematic literature review and qualitative thematic synthesis.

DATA SOURCE

MEDLINE, Embase, CINAHL, PsycINFO (until 10/2016; limited to English) were searched. Eligible papers were qualitative studies of adult patients' experience of cancer-associated thrombosis. Two researchers screened titles/abstracts/papers against inclusion criteria with recourse to a third for disagreements. Critical Appraisal Skills Programme qualitative checklist tool was used for quality appraisal.

RESULTS

A total of 1397 articles were identified. Five qualitative studies (total n = 92; age range 32-84 years) met the inclusion criteria. Participants had various cancer types. Most had advanced disease and were receiving palliative care. Four major themes emerged from the data: knowledge deficit (patients and clinicians), effects of cancer-associated thrombosis (physical and psychological), effects of anticoagulation and coping strategies.

CONCLUSION

The cancer journey is difficult in itself, but thrombosis was an additional, frightening and unexpected burden. Although the association between cancer and thromboembolism is well-known, cancer patients are not routinely educated about the risk or warning symptoms/signs of thromboembolism which may otherwise be misattributed to the cancer by patient and clinician alike. This systematic review highlights the impact of cancer-associated thrombosis on the lives of cancer patients, and calls for education for patients and clinicians to be part of routine care and further work to address this patient priority.

Venöse Thrombembolien bei Tumorpatienten

Venous thrombembolism (VTE) is one of the most frequent complication in cancer patients. The current options in prophylaxis and therapy have to be balanced against the risks of major bleeding and the burden for the patients. The Gesellschaft für Thrombose- und Hämostaseforschung, the Deutsche Gesellschaft für Palliativmedizin and the German speaking Societies of Hematology and Oncology have recently published guidelines on VTE in cancer patients. Recommendations include diagnostics, individual prophylaxis and treatment.

Neutrophil extracellular traps are increased in cancer patients but does not associate with venous thrombosis

Background

A single center, prospective tissue-based study was conducted to investigate an association between neutrophil extracellular traps (NETs) and venous thromboembolic disease in patients with malignancy.

Methods

Plasma was collected from 65 patients in which 27 were cancer patients and 38 were age-matched non-cancer patients. Plasma NETs, circulating free DNA (cfDNA), DNase-1, endonuclease-G, endonuclease activity and thrombin-antithrombin III (TAT) complex levels was quantified. Laboratory values were also compared. Additionally, NETs detection and quantification was performed with fluorescent immunohistochemistry (IHC) in tissue-banked tumor sections and fresh human venous thrombus derived from cancer patients.

Results

Plasma samples from cancer patients contained higher levels of nucleosomes (P=0.0009) and cfDNA (P=0.0008) compared to the non-cancer group. Western blot analysis revealed significantly lower DNase-1 protein levels (P=0.016) that paralleled lower nuclease activity (P=0.03) in plasma samples from cancer patients compared to non-cancer patients. Thrombus tissue from cancer patients and tumor tissue from liver and lung cancer also showed marked levels of NETs. However, increased levels of NETs in cancer patients did not correlate with TAT complex activation or prevalence of venous thrombosis in cancer patients.

Conclusions

Further studies are warranted to determine the role of NETs as a procoagulant in human thrombosis.

Mecanismos do tromboembolismo venoso no câncer: uma revisão da literatura

Existe uma estreita relação entre o tromboembolismo venoso e o câncer. Pacientes com neoplasias apresentam maior incidência de eventos tromboembólicos em sua evolução clínica. A ocorrência desses eventos é considerada um marcador preditivo negativo nesse grupo de pacientes. Revisamos, então, a ativação dos mecanismos de coagulação neste grupo de pacientes. Trata-se de um processo complexo e multifatorial, relacionado tanto a características tumorais, estadiamento clínico, agressividade da doença e sítios tumorais, dentre outros. Novos biomarcadores vêm sendo pesquisados ao longo dos anos na tentativa de correlacioná-los ao risco trombótico, visando uma intervenção que melhore a evolução clínica desses pacientes oncológicos.

Cancer associated thrombosis: risk factors and outcomes

Deep vein thrombosis of the leg and pulmonary embolism are frequent diseases and cancer is one of their most important risk factors. Patients with cancer also have a higher prevalence of venous thrombosis located in other parts than in the legs and/or in unusual sites including upper extremity, splanchnic or cerebral veins. Cancer also affects the risk of arterial thrombotic events particularly in patients with myeloproliferative neoplasms and in vascular endothelial growth factor receptor inhibitor recipients. Several risk factors need to interact to trigger thrombosis. In addition to common risk factors such as surgery, hospitalisation, infection and genetic coagulation disorders, the thrombotic risk is also driven and modified by cancer-specific factors including type, histology, and stage of the malignancy, cancer treatment and certain biomarkers. A venous thrombotic event in a cancer patient has serious consequences as the risk of recurrent thrombosis, the risk of bleeding during anticoagulation and hospitalisation rates are all increased. Survival of cancer patients with thrombosis is worse compared to that of cancer patients without thrombosis, and thrombosis is a leading direct cause of death in cancer patients.

Tissue factor expressed by circulating cancer cell-derived microparticles drastically increases the incidence of deep vein thrombosis in mice

BACKGROUND

The risk of thrombotic complications such as deep vein thrombosis (DVT) during tumor development is well known. Tumors release into the circulation procoagulant microparticles (MPs) that can participate in thrombus formation following vessel injury. The importance of this MP tissue factor (TF) in the initiation of cancer-associated DVT remains uncertain.

OBJECTIVE

To investigate how pancreatic cancer MPs promote DVT in vivo.

METHODS

We combined a DVT mouse model in which thrombosis is induced by flow restriction in the inferior vena cava with one of subcutaneous pancreatic cancer in C57BL/6J mice. We infused high-TF and low-TF tumor MPs to determine the importance of TF in experimental cancer-associated DVT.

RESULTS

Both tumor-bearing mice and mice infused with tumor MPs subjected to 3 h of partial flow restriction developed an occlusive thrombus; fewer than one-third of the control mice did. We observed that MPs adhered to neutrophil extracellular traps (NETs), which are functionally important players during DVT, whereas neither P-selectin nor glycoprotein Ib were required for MP recruitment in DVT. The thrombotic phenotype induced by MP infusion was suppressed by hirudin, suggesting the importance of thrombin generation. TF carried by tumor MPs was essential to promote DVT, as mice infused with low-TF tumor MPs had less thrombosis than mice infused with high-TF tumor MPs.

CONCLUSIONS

TF expressed on tumor MPs contributes to the increased incidence of cancer-associated venous thrombosis in mice in vivo. These MPs may adhere to NETs formed at the site of thrombosis.

Altered plasma levels of cytokines, soluble adhesion molecules and matrix metalloproteases in venous thrombosis

BACKGROUND/AIM

Recent studies have emphasized the importance of the inflammatory response mediated by monocyte and neutrophil activation in deep venous thrombosis (DVT); we therefore investigated whether this response was reflected in the plasma profile of inflammatory mediators in patients with suspected DVT.

METHODS

We included a group of 169 consecutive patients admitted to hospital from the primary health care service with suspected lower limb DVT. Plasma levels of 43 mediators were examined for a cohort of 89 consecutive patients and 20 healthy controls by Luminex multiplex analyses, i.e. 13 interleukins, 3 immunomodulatory cytokines, 8 chemokines, 8 growth factors, 3 adhesion molecules and 8 matrix metalloproteases. Selected mediators were analyzed for a second cohort of 80 consecutive patients.

RESULTS

Thirty-five of 169 (21%) of referred patients were diagnosed with DVT. Only P-selectin (p<0.0001), vascular cell adhesion protein 1 (VCAM-1, p=0.0009), matrix metalloprotease 8 (MMP-8, p=0.0151) and hepatocyte growth factor (HGF, p=0.0415) differed significantly when comparing patients with and without DVT. When comparing DVT patients with healthy controls we observed significant differences for several mediators, where P-selectin (p=0.0009), VCAM-1 (p<0.0001), all the MMPs (all p<0.0014) and HGF (p<0.0001) showed the strongest significant differences. Unsupervised hierarchical clustering analyses based on biomarkers showing differences between patients with and without DVT could be used to identify patient subsets that differed significantly in DVT frequency.

CONCLUSION

Plasma biomarker profiling of selected soluble mediators can be used to identify subsets among patients with suspected lower limb thrombosis that differ significantly in their frequencies of DVT.

Predicting recurrent venous thromboembolism in cancer: is it possible?

The association between cancer and venous thromboembolism (VTE) is well-established. Many clinical and laboratory risk factors of a first cancer-associated VTE have been identified. In contrast, the pathogenesis of recurrent VTE in cancer patients is less well studied. There is only very limited information on the importance of clinical risk factors and the role of biomarkers in this context has never been studied. Patients with cancer-associated VTE usually receive low-molecular-weight heparin for at least 3 to 6 months. Nevertheless, the recurrence risk during anticoagulation is as high as 10% and treatment-related major bleeding is more common in cancer-patient than in non-cancer patients. Thus improvement of current treatment concepts is warranted. One important step to achieve this task is developing strategies that allow distinguishing patients with a high risk of recurrent VTE (who may benefit from prolonged or even intensified anticoagulation) from those with a low risk (i.e. patients in whom a shorter period of anticoagulant treatment at lower dose may be sufficient). Recently, a risk assessment model (RAM) for predicting recurrent VTE has been presented. By combining 4 clinical patient characteristics (sex, cancer type and stage, history of VTE), the Ottawa score allows stratification of cancer patients according to their VTE recurrence risk. The prediction tool was successfully validated in more than 800 patients from 2 prospective VTE treatment studies. Before this RAM can be introduced into routine clinical practice, however, management studies and impact analyses are required.

Primary thromboprophylaxis in hospices: the association between risk of venous thromboembolism and development of symptoms

CONTEXT

Venous thromboembolism (VTE) risk assessment for adults admitted to hospital is commonplace, but the utility of assessment tools in patients admitted to hospices or palliative care units and prediction of symptomatic VTE is unknown.

OBJECTIVES

To investigate the relationship between risk of VTE and development of symptoms.

METHODS

Retrospective consecutive admission, case-note data from seven U.K. hospices were collected during an evaluation of a VTE risk assessment protocol using the Pan Birmingham Cancer Network palliative-modified Thromboembolic Risk Factors (THRIFT) Consensus Group criteria and presence/absence of a temporary elevated risk (TER) of VTE. Symptoms/signs during admission consistent with possible VTE were documented.

RESULTS

A total of 1164 case-notes were analyzed (age range 23-99; men 627). THRIFT risk was high in 13%, medium in 83%, and low in 4%; a TER was identified in 24%. In the "clinically relevant group" (no contraindication, not anticoagulated), where primary thromboprophylaxis could have been prescribed (n = 528), TER and symptoms were associated (21% symptoms with TER vs. 9% symptoms without TER: Chi-squared, P < 0.001). A high/moderate THRIFT score had a sensitivity of 98.4% (95% CI 91.3%-99.9%) and specificity of 5.8% (95% CI 3.9%-8.3%). The TER assessment had a more evenly balanced sensitivity (41.9%; 95% CI 29.5%-55.2%) and specificity (79%; 95% CI 75.0%-82.6%).

CONCLUSION

Hospice inpatients are at risk for VTE. TER alone is simpler to use and may be more useful in this population than the THRIFT but still has limitations regarding ability to predict symptoms.

Clinical and prognostic significance of coagulation assays in gastric cancer

PURPOSE

Activation of coagulation and fibrinolysis is frequently found among cancer patients. Such tumors are considered to be associated with a higher risk of invasion, metastases, and eventually, worse outcome. The aim of this study is to explore the clinical and prognostic value of blood coagulation tests in gastric cancer (GC) patients.

MATERIALS AND METHODS

A total of 44 consecutive patients with a pathologically confirmed diagnosis of GC were enrolled into the study. Pretreatment blood coagulation tests including prothrombin time (PT), activated partial thromboplastin time (APTT), international normalized ratio (INR), D-dimer (DD), fibrinogen (F) levels, and platelet (PLT) counts were evaluated. Control group comprised 50 age- and sex-matched individuals without history of malignancy and coagulation disorder.

RESULTS

Median age at diagnosis was 55 years, range 19-80 years; most had men (n = 32, 73 %) and metastatic disease (n = 31, 70 %). The level of blood coagulation tests showed a statistically significant difference between the patient and the control groups (P < 0.001 for all, but p = 0.07 for PT). DD levels were significantly associated with elevated PLT and LDH levels (p = 0.009 and p = 0.01, respectively). Patients with metastatic disease had higher levels of F (p = 0.001) and INR (p = 0.027) levels. Elevated DD levels tended to be a poor prognostic factor on outcome (p = 0.06).

CONCLUSION

Change in almost all coagulation tests are found in GC patients and only DD level seems to be of prognostic value.

NETosis: a new factor in tumor progression and cancer-associated thrombosis

Neutrophils have long been known as innate immune cells that phagocytose and kill pathogens and mount inflammatory responses protecting the host from infection. In the past decades, new aspects of neutrophils have emerged unmasking their importance not only in inflammation but also in many pathological conditions including thrombosis and cancer. The 2004 discovery that neutrophils, upon strong activation, release decondensed chromatin to form neutrophil extracellular traps (NETs), has unveiled new avenues of research. Here, we review current knowledge regarding NETs in thrombosis, with a special focus on cancer-associated thrombosis as well as their potential role in cancer growth and metastasis. We discuss the prospective use of NET-specific biomarkers, such as citrullinated histone H3 and NET inhibitors, as tools to anticipate and fight cancer-associated thrombosis. We propose that the rapid developments in the field of NETosis may provide new targets to combat the thrombotic consequences of cancer and perhaps even help to contain the disease itself.

Infections increase the risk of central venous catheter-related thrombosis in adult acute myeloid leukemia

INTRODUCTION

Central venous catheters (CVC) related thrombosis (CRT) represents a well known complication in patients with acute myeloid leukemia (AML) receiving intensive chemotherapy but the efficacy of antithrombotic prophylaxis still remains controversial.

PATIENTS AND METHODS

We analyzed 71 consecutive AML patients whose CVC was inserted before each chemotherapy cycle for an overall number of 106 CVC placements. In 47/106 insertions, a prophylaxis with 100 IU/kg/day low molecular weight heparin (LMWH) was administered for 7 days after CVC insertion and additional 7 after CVC removal. This unconventional dose of LMWH, although higher than usual, appeared adequate for a short-course approach. LMWH was delivered regardless of the platelet (PLT) count once provided that it should have been maintained above 20 x 10(9)/L by transfusions.

RESULTS

Of 106 insertions, we observed 19 (18%) episodes of CRT, 58 (54%) of sepsis and 50 (47%) infections of CVC-exit site with no difference between LMWH and no-LMWH group. Occurrence of CRT was significantly associated with CVC-exit site infections (14/19, p=0.01) and sepsis (16/19, p=0.005) with no difference between LMWH and no-LMWH group. In multivariate analysis, both CVC-exit site infections and sepsis were confirmed to be independent risk factors for CRT development.

CONCLUSION

Our retrospective study, although based on a small sample size, suggests that the occurrence of CVC-exit site infections and neutropenic sepsis following chemotherapy significantly increases the risk of CRT in AML, independently from the use of LMWH prophylaxis.

Regional lymph node metastases are a strong risk factor for venous thromboembolism: results from the Vienna Cancer and Thrombosis Study

Advanced cancer is a risk factor for venous thromboembolism. However, lymph node metastases are usually not considered an established risk factor. In the framework of the prospective, observational Vienna Cancer and Thrombosis Study we investigated the association between local (N0), regional (N1-3), and distant (M1) cancer stages and the occurrence of venous thromboembolism. Furthermore, we were specifically interested in the relationship between stage and biomarkers that have been reported to be associated with venous thromboembolism. We followed 832 patients with solid tumors for a median of 527 days. The study end-point was symptomatic venous thromboembolism. At study inclusion, 241 patients had local, 138 regional, and 453 distant stage cancer. The cumulative probability of venous thromboembolism after 6 months in patients with local, regional and distant stage cancer was 2.1%, 6.5% and 6.0%, respectively (P=0.002). Compared to patients with local stage disease, patients with regional and distant stage disease had a significantly higher risk of venous thromboembolism in multivariable Cox-regression analysis including age, newly diagnosed cancer (versus progression of disease), surgery, radiotherapy, and chemotherapy (regional: HR=3.7, 95% CI: 1.5-9.6; distant: HR=5.4, 95% CI: 2.3-12.9). Furthermore, patients with regional or distant stage disease had significantly higher levels of D-dimer, factor VIII, and platelets, and lower hemoglobin levels than those with local stage disease. These results demonstrate an increased risk of venous thromboembolism in patients with regional disease. Elevated levels of predictive biomarkers in patients with regional disease underpin the results and are in line with the activation of the hemostatic system in the early phase of metastatic dissemination.

Clinical and prognostic significance of coagulation assays in melanoma

The activation of coagulation and fibrinolysis is frequently found among cancer patients. Such tumors are considered to be associated with a higher risk of invasion, metastases, and eventually worse outcome. The aim of this study is to explore the clinical and prognostic value of blood coagulation tests for melanoma patients. Pretreatment blood coagulation tests including prothrombin time (PT), activated partial thromboplastin time (APTT), prothrombin activity (PTA), international normalized ratio (INR), D-dimer (DD), fibrinogen (F) levels, and platelet (PLT) counts were carried out. This prospective study included 61 melanoma patients [stage I-II (n=10), stage III (n=14), stage IV (n=37), M1c (n=26) disease], and 50 healthy controls. It included 34 (56%) men, median age 53 years, range 16-88 years. Over half of the patients (54%) were in the metastatic stage and most of them (70%) had M1c. The plasma level of pretreatment blood coagulation tests including DD, F, APTT, INR levels, and PLT counts showed a statistically significant difference between the patient and the control group (P<0.001 for all, but P=0.049 for INR). The levels of INR, DD, F, and PLT counts were higher and APTT was lower in the melanoma group, whereas the PT and PTA levels did not show any significant difference. There was a significant association between PT, PTA, INR, and PLT levels and the age of the patient. Patients with node metastasis in M0 disease had higher levels of PTA and PLT counts (P=0.002 and 0.048, respectively) and lower levels of PT and INR (P=0.056 and 0.046, respectively). The M1c patients tended to have higher plasma F levels (437 vs. 297 mg/dl, P=0.055) than M1a and M1b patients. The 1-year survival rate for all patients was 70%. In association with distant metastasis, advanced metastatic stage (M1c), elevated lactate dehydrogenase, and erythrocyte sedimentation rate, only elevated plasma F levels had a significantly adverse effect on survival among the coagulation parameters (P=0.031). The 1-year survival rates for patients with high and normal F levels were 58 and 88%, respectively. In conclusion, changes in the coagulation-fibrinolytic system are often present in melanoma and elevation in the plasma F level is associated with decreased survival.

Implications of new anticoagulants in primary practice

BACKGROUND

Effective prophylaxis and treatment of thromboembolic disorders remain suboptimal in many healthcare systems, partly owing to limitations of traditional anticoagulants. New oral anticoagulants have been developed and among these, rivaroxaban, apixaban and dabigatran etexilate are in the most advanced stage of clinical development.

METHOD

A literature search using the PubMed and ClinicalTrials.gov databases was performed to identify English-language publications. The search was performed up to 31 December 2011 with the terms rivaroxaban OR Xarelto, apixaban OR Eliquis and dabigatran OR Pradaxa. Ongoing, completed and published phase III randomised controlled trials were selected as the primary source of information for the clinical development programme of each drug.

RESULTS

The new oral agents demonstrate several advantages over traditional anticoagulants, including administration at fixed doses and no requirement for routine coagulation monitoring On the basis of phase III clinical trials, rivaroxaban, apixaban and dabigatran etexilate have been approved in many countries for the prevention of venous thromboembolism after hip and knee replacement surgery. Dabigatran etexilate and rivaroxaban have also been approved for the prevention of stroke and systemic embolism in patients with non-valvular atrial fibrillation in Europe and the US. In addition, rivaroxaban has been approved in Europe for the treatment of acute deep vein thrombosis and prevention of recurrent venous thromboembolism. Approval of these agents and postapproval monitoring of their safety and efficacy will have implications for primary care.

CONCLUSION

Rivaroxaban, apixaban and dabigatran etexilate offer the possibility of simplified prevention and treatment strategies for thromboembolic disorders in the outpatient setting.

Tumor Grade Is Associated With Venous Thromboembolism in Patients With Cancer: Results From the Vienna Cancer and Thrombosis Study

Purpose

Patients with cancer are at risk of venous thromboembolism (VTE). Tumor-related factors could help estimate patients' individual risk for VTE. Currently, only scarce information on the association between tumor grade and VTE is available. We thus evaluated the role of tumor grade and its association with VTE.

Patients and Methods

The Vienna Cancer and Thrombosis Study is a prospective, observational cohort study including patients with newly diagnosed cancer or progression of disease after remission. Study end point is the occurrence of symptomatic VTE.

Results

Seven hundred forty-seven patients with solid tumors received follow-up for a median of 526 days. VTE occurred in 52 patients (7.0%). At study inclusion, 468 patients had low-grade tumors (G1 and G2) and 279 had high-grade tumors (G3 and G4). In multivariable Cox regression analysis including tumor grade, tumor histology, tumor sites, stage, sex, and age, patients with high-grade tumors had a significantly higher risk of VTE compared with those with low-grade tumors (hazard ratio, 2.0; 95% CI, 1.1 to 3.5; P = .015). The cumulative probability of developing VTE after 6 months was higher in patients with high-grade tumors than in those with low-grade tumors (8.2% v 4.0%; log-rank test P = .037). Patients with high-grade tumors had higher D-dimer levels (P = .008) and leukocyte counts (P < .001), and lower hemoglobin levels (P = .008).

Conclusion

The tumor grade may help identify patients with cancer who are at high risk of VTE. The association of tumor grade with recently identified biomarkers indicates a link between tumor differentiation and pathogenesis of cancer-associated VTE.

Acute pulmonary embolism

Venous thromboembolism is the third leading cause of cardiovascular death in the United States and is the second leading cause of death among hospitalized cancer patients. Continued controversy exists regarding the role of thrombolytic therapy among patients with acute pulmonary embolism. Limited research exists on thrombolytic therapy in this setting, most of which has focused on symptoms, including right ventricular function, hemodynamic status, and electrocardiographic changes. However, these studies have excluded patients with a known malignancy. Presented is an interesting case of a patient, in remission from breast cancer, who presented to the emergency department with symptomatic pulmonary emboli. The presentation, medical management, and consequences of the treatment have been discussed. Also, a brief review of the literature is presented regarding the treatment of acute pulmonary embolism.

Cancers predispose neutrophils to release extracellular DNA traps that contribute to cancer-associated thrombosis

Cancer-associated thrombosis often lacks a clear etiology. However, it is linked to a poor prognosis and represents the second-leading cause of death in cancer patients. Recent studies have shown that chromatin released into blood, through the generation of neutrophil extracellular traps (NETs), is procoagulant and prothrombotic. Using a murine model of chronic myelogenous leukemia, we show that malignant and nonmalignant neutrophils are more prone to NET formation. This increased sensitivity toward NET generation is also observed in mammary and lung carcinoma models, suggesting that cancers, through a systemic effect on the host, can induce an increase in peripheral blood neutrophils, which are predisposed to NET formation. In addition, in the late stages of the breast carcinoma model, NETosis occurs concomitant with the appearance of venous thrombi in the lung. Moreover, simulation of a minor systemic infection in tumor-bearing, but not control, mice results in the release of large quantities of chromatin and a prothrombotic state. The increase in neutrophil count and their priming is mediated by granulocyte colony-stimulating factor (G-CSF), which accumulates in the blood of tumor-bearing mice. The prothrombotic state in cancer can be reproduced by treating mice with G-CSF combined with low-dose LPS and leads to thrombocytopenia and microthrombosis. Taken together, our results identify extracellular chromatin released through NET formation as a cause for cancer-associated thrombosis and unveil a target in the effort to decrease the incidence of thrombosis in cancer patients.