Direct oral anticoagulants in patients with VTE and cancer: a systematic review and meta-analysis

Intensive care in thoracic oncology

The admission of lung cancer patients to intensive care is related to postprocedural/postoperative care and medical complications due to cancer or its treatment, but is also related to acute organ failure not directly related to cancer.

Despite careful preoperative risk management and the use of modern surgical and anaesthetic techniques, thoracic surgery remains associated with high morbidity, related to the extent of resection and specific comorbidities. Fast-tracking processes with timely recognition and treatment of complications favourably influence patient outcome. Postoperative preventive and therapeutic management has to be carefully planned in order to reduce postoperative morbidity and mortality.

For patients with severe complications, intensive care unit (ICU) mortality rate ranges from 13% to 47%, and hospital mortality ranges from 24% to 65%. Common predictors of in-hospital mortality are severity scores, number of failing organs, general condition, respiratory distress and the need for mechanical ventilation or vasopressors. When considering long-term survival after discharge, cancer-related parameters retain their prognostic value.

Thoracic surgeons, anesthesiologists, pneumologists, intensivists and oncologists need to develop close and confident partnerships aimed at implementing evidence-based patient care, securing clinical pathways for patient management while promoting education, research and innovation. The final decision on admitting a patient with lung to the ICU should be taken in close partnership between this medical team and the patient and his or her relatives.

Long-term treatment of cancer-associated thrombosis: the choice of the optimal anticoagulant

Patients with cancer-associated thrombosis (CAT) carry a higher risk of recurrence, bleeding and mortality as compared with non-cancer patients. The specific profiles of cancer patients, combining frequent co-morbidities, the use of anti-tumoral therapies and the cancer progression itself, represent a major therapeutic challenge for choosing a long-term anticoagulant treatment. This review discusses the practical basis of making a choice between the available drugs for a long-term antithrombotic strategy, linked to their pharmacology, mechanism of action, evidence of clinical benefits, and advantages and limitations in such a complex clinical context. In patients with cancer, low-molecular-weight heparins (LMWHs) are the preferred option for the secondary prevention of venous thromboembolism according to current guidelines, because their efficacy is significantly superior to vitamin K antagonists (VKAs). Even though LMWHs are effective and safe in cancer patients, they require daily subcutaneous injections, which may be problematic for a long-term therapy that may exceed 6 months' duration. Compared with VKAs, non-vitamin-K antagonist oral anticoagulants or direct oral anticoagulants (DOACs) are more target specific and do not require laboratory monitoring, whereas the oral route of administration makes them potentially attractive alternatives to LMWH. In randomized controlled trials in the general population DOACs have been shown to be non-inferior to VKAs in terms of efficacy with a lower rate of clinically relevant or major bleeding. However, given the limited number of cancer patients enrolled in these studies (with poorly defined active cancer), available trials are inconclusive regarding the usefulness of DOACs in the cancer setting. Ongoing head-to-head comparisons vs. LMWH in patients with CAT may allow an informed choice to be made regarding the DOAC option.

ANMCO Position Paper: the use of non-vitamin K dependent new oral anticoagulant(s) in pulmonary embolism therapy and prevention

The new oral anticoagulants (NOACs) have radically changed the approach to the treatment and prevention of thromboembolic pulmonary embolism. The authors of this position paper face, in succession, issues concerning NOACs, including (i) their mechanism of action, pharmacodynamics, and pharmacokinetics; (ii) the use in the acute phase with the 'double drug single dose' approach or with 'single drug double dose'; (iii) the use in the extended phase with demonstrated efficacy and with low incidence of bleeding events; (iv) the encouraging use of NOACs in particular subgroups of patients such as those with cancer, the ones under- or overweight, with renal insufficiency (creatinine clearance > 30 mL/min), the elderly (>75 years); (v) they propose a possible laboratory clinical pathway for follow-up; and (vi) carry out an examination on the main drug interactions, their potential bleeding risk, and the way to deal with some bleeding complications. The authors conclude that the use of NOACs both in the acute phase and in the extended phase is equally effective to conventional therapy and associated with fewer major bleeding events, which make their use in patients at higher risk of recurrences safer.

Direct oral anticoagulants and venous thromboembolism

Venous thromboembolism (VTE), consisting of deep vein thrombosis and pulmonary embolism, is a major clinical concern associated with significant morbidity and mortality. The cornerstone of management of VTE is anticoagulation, and traditional anticoagulants include parenteral heparins and oral vitamin K antagonists. Recently, new oral anticoagulant drugs have been developed and licensed, including direct factor Xa inhibitors (e.g. rivaroxaban, apixaban and edoxaban) and thrombin inhibitors (e.g. dabigatran etexilate). This narrative review focusses on the characteristics of these direct anticoagulants and the main results of published clinical studies on their use in the prevention and treatment of VTE.

A prospective study of Rivaroxaban for central venous catheter associated upper extremity deep vein thrombosis in cancer patients (Catheter 2)

INTRODUCTION

Patients with cancer are at increased risk of thrombosis, particularly those with central venous catheter (CVC) placement, which may predispose to the development of upper extremity deep vein thrombosis (UEDVT). Standard treatment includes low molecular weight heparin (LMWH) or LMWH bridged to warfarin. The direct oral anticoagulants (DOACs) have become standard of care for uncomplicated venous thromboembolism (VTE), but research in patients with cancer is ongoing.

OBJECTIVES

To assess rivaroxaban monotherapy in patients with cancer who develop UEDVT due to CVC for preservation of line function, and safety outcomes of VTE recurrence, bleeding risk and death.

MATERIALS AND METHODS

Patients ≥18years of age with active malignancy and symptomatic proximal UEDVT with or without pulmonary embolism (PE), associated with a CVC, were eligible. Treatment included rivaroxaban 15mg oral twice daily for 3weeks, followed by 20mg oral daily for 9weeks. Patients were followed clinically for 12weeks to assess for line function, recurrent VTE and bleeding.

RESULTS

Seventy patients (47 women) were included, with mean age 54.1years. The most common malignancy was breast cancer (41%). Preservation of line function was 100% at 12weeks. The risk of recurrent VTE at 12weeks was 1.43%, with one episode of fatal PE. 9 patients (12.9%) experienced 11 total bleeding episodes.

CONCLUSIONS

Rivaroxaban showed promise in treating CVC-UEDVT in cancer patients, resulting in preserved line function. However, bleeding rates and a fatal pulmonary embolism on treatment are concerning safety outcomes necessitating further study before rivaroxaban can be recommended.

Italian intersociety consensus on DOAC use in internal medicine

The direct oral anticoagulants (DOACs) are drugs used in clinical practice since 2009 for the prevention of stroke or systemic embolism in non-valvular atrial fibrillation, and for the treatment and secondary prevention of venous thromboembolism. The four DOACs, including the three factor Xa inhibitors (rivaroxaban, apixaban and edoxaban) and one direct thrombin inhibitor (dabigatran) provide oral anticoagulation therapy alternatives to Vitamin K antagonists (VKAs). Despite their clear advantages, the DOACs require on the part of the internist a thorough knowledge of their pharmacokinetic and pharmacodynamic characteristics to ensure their correct use, laboratory monitoring and the appropriate management of adverse events. This document represents a consensus paper on the use of DOACs by representatives of three Italian scientific societies: the Italian Society of Internal Medicine (SIMI), the Federation of the Associations of Hospital Managers (FADOI), and the Society for the Study of Haemostasis and Thrombosis (SISET). This document formulates expert opinion guidance for pragmatic managing, monitoring and reversing the anticoagulant effect of DOACs in both chronic and emergency settings. This practical guidance may help the internist to create adequate protocols for patients hospitalized ion internal medicine wards, where patients are often elderly subjects affected by poly-morbidities and renal insufficiency, and, thus, require particular attention to drug-drug interactions and peri-procedural protocols.

Ischemic stroke in cancer patients treated with direct oral anticoagulants for venous thromboembolism

Direct oral anticoagulants (DOACs) are at least as efficacious as conventional anticoagulation therapy for the initial and long-term treatment of cancer patients with venous thromboembolism (VTE). Whether DOACs are non-inferior to low-molecular-weight heparin for the management of cancer patients with VTE is under investigation. In addition, the efficacy of DOACs for the treatment of cancer patients with arterial thrombosis (e.g., ischemic stroke) remains unclear. Herein, we report on two cancer patients admitted to our hospital with Stage IV gastric adenocarcinoma who were being treated with DOACs due to a history of VTE and had developed their first ever ischemic stroke, which was diagnosed due to cancer-related hypercoagulation. Notably, neither patient had recurrence of VTE during the course of their disease. In cancer-related thrombosis, DOACs effectively reduce VTE, but may be insufficient for preventing ischemic stroke.

Initiating and Managing Patients with Venous Thromboembolism on Anticoagulant Drugs: A Practical Overview

Several new oral anticoagulants have recently been approved for the treatment of venous thromboembolism (VTE). In this review, we discuss the currently approved drugs and the factors that influence the choice of anticoagulant in a given patient. Once anticoagulation is initiated, periodic monitoring of adequacy of anticoagulation may be necessary depending on the choice of anticoagulant and patient-related factors, such as renal function. Situations that may warrant need for monitoring and the tests available for this purpose are discussed. We review reversal of anticoagulation in urgent/emergent situations as well as perioperative anticoagulation interruption in the elective setting. The data on use of direct oral anticoagulants in patients with compromised renal function, obesity and bariatric surgery, and in the treatment of cancer-associated thrombosis are discussed. The review aims to provide the clinician with the essential information to allow effective and safe use of anticoagulants for the treatment of VTE.

Anticoagulants versus cancer

Venous thromboembolism (VTE) and cancer are strongly associated, and present a major challenge in cancer patient treatment. Cancer patients have a higher risk of developing VTE, although the risk differs widely between tumour types. VTE prophylaxis is routinely given to cancer patients, in the form of vitamin K antagonists (VKA) or low molecular weight heparin (LMWH). Several studies have reported that cancer patients receiving anticoagulants show prolonged survival and this effect was more pronounced in patients with a good prognosis, although the mechanism is poorly understood. Tissue Factor (TF) is the initiator of extrinsic coagulation, but its non-haemostatic signalling via protease-activated receptors (PARs) is a potent driver of tumour angiogenesis. Furthermore, coagulation activation is strongly implicated in tumour cell migration and metastasis. This review discusses the effects of anticoagulants on cancer progression in patients, tumour cell behaviour, angiogenesis, and metastasis in in vitro and in vivo models. Inhibition of TF signalling shows great promise in curbing angiogenesis and in vivo tumour growth, but whether this translates to patients is not yet known. Furthermore, non-haemostatic properties of coagulation factors in cancer progression are discussed, which provide exciting opportunities on limiting oncologic processes without affecting blood coagulation.

Management of recurrent venous thromboembolism in cancer patients

Cancer is one the most prevalent risk factors in patients diagnosed with deep vein thrombosis or pulmonary embolism. Patients with cancer and venous thromboembolism have a higher risk of mortality when compared to patients with cancer without venous thromboembolism and a higher risk of recurrent thrombosis when compared with patients with venous thromboembolism without cancer. This increased risk of recurrence is not only observed after anticoagulant treatment is stopped, but also during anticoagulant treatment. Clinical trials have shown that the use of low molecular weight heparin during the first three to six months after venous thrombosis in patients with cancer is associated with a significantly lower risk of recurrence than the use of vitamin K antagonists and, thus, low molecular weight heparin is currently recommended as the treatment of choice by international guidelines. Unfortunately, the optimal management of recurrent venous thromboembolism during anticoagulant treatment remains poorly defined. In general, patients should firstly be assessed for treatment compliance, for the occurrence of heparin-induced thrombocytopenia, and for the presence of mechanical compression from tumour masses. Possible strategies include switching to a different anticoagulant drug, in particular from vitamin K antagonists to low molecular weight heparin; increasing the dose of the anticoagulant drug; or inserting an inferior vena cava filter. The results of recent registries show that the current approach to cancer patients with recurrent venous thromboembolism in routine clinical practice is highly heterogeneous.

Assessment of the Safety and Efficacy of Edoxaban for the Treatment of Venous Thromboembolism Secondary to Active Malignancy

Objective: To assess the safety and efficacy of edoxaban for the treatment of venous thromboembolism (VTE) secondary to active malignancy.

Materials and Methods: We enrolled 48 patients with newly diagnosed VTE secondary to active malignancy that was treated with oral edoxaban for 1 year between September 2014 and August 2015. We retrospectively examined the presence or absence of recurrent symptomatic VTE, VTE-related mortality, and bleeding events.

Results: No recurrent symptomatic VTE or VTE-related deaths were recorded, enabling efficient assessment. Treatment safety was determined based on the reports of bleeding. Bleeding was reported in two patients, with serious bleeding in one of them.

Conclusion: Edoxaban is safe and effective for the treatment of VTE secondary to active malignancy.

Comparative effectiveness and safety of direct oral anticoagulants (DOACs) versus conventional anticoagulation for the treatment of cancer-related venous thromboembolism: A retrospective analysis

PURPOSE

The standard of care for the treatment of cancer-related venous thromboembolism (VTE) is a low molecular weight heparin (LMWH) formulation. The recent development of direct oral anticoagulants (DOACs) and their approval for the treatment of VTE has resulted in several new options for treatment. If equivalent to LMWH in terms of safety and effectiveness, the use of DOACs in the treatment of cancer-related VTE would reduce the risk of VTE recurrence while potentially improving the quality of life of many cancer patients.

METHODS

We performed a retrospective analysis of adult patients with cancer-related VTE treated in our benign hematology clinic. Among the 153 patients included in our final analysis, 123 (80%) were treated with LMWH and 30 (20%) were treated with DOACs. Patients had 36 different histological types of cancer. The primary outcome was the rate of recurrence of VTE evaluated at 6 and 12months after the initiation of anticoagulation. Secondary outcomes were the rate of anticoagulant-associated clinically relevant bleeding and event-free survival for VTE recurrence.

RESULTS

In comparing the 2 treatment groups, there was no statistically significant difference in the cumulative rates of VTE recurrence at 6 and 12months or in the rates of major or non-major bleeding at both 6 and 12months. The median VTE recurrence-free survival rates were not reached and they were not statistically different.

CONCLUSION

DOACs appear to be as safe and effective as conventional therapy for the treatment of cancer-related VTE. Results of ongoing randomized clinical studies may provide definitive evidence and clarify the role of the DOACs in the setting of malignancy.

Hypercoagulability and Mortality of Patients with Stroke and Active Cancer: The OASIS-CANCER Study

Background and Purpose

Patients with active cancer are at an increased risk for stroke. Hypercoagulability plays an important role in cancer-related stroke. We aimed to test whether 1) hypercoagulability is a predictor of survival, and 2) correction of the hypercoagulable state leads to better survival in patients with stroke and active cancer.

Methods

We recruited consecutive patients with acute ischemic stroke and active systemic cancer between January 2006 and July 2015. Hypercoagulability was assessed using plasma D-dimer levels before and after 7 days of anticoagulation treatment. The study outcomes included overall and 1-year survival. Plasma D-dimer levels before and after treatment were tested in univariate and multivariate Cox regression models. We controlled for systemic metastasis, stroke mechanism, age, stroke severity, primary cancer type, histology, and atrial fibrillation using the forward stepwise method.

Results

A total of 268 patients were included in the analysis. Patients with high (3rd–4th quartiles) pre-treatment plasma D-dimer levels showed decreased overall and 1-year survival (adjusted HR, 2.19 [95% CI, 1.46–3.31] and 2.70 [1.68–4.35], respectively). After anticoagulation treatment, post-treatment D-dimer level was significantly reduced and independently associated with poor 1-year survival (adjusted HR, 1.03 [95% CI, 1.01–1.05] per 1 μg/mL increase, P=0.015). The successful correction of hypercoagulability was a protective factor for 1-year survival (adjusted HR 0.26 [CI 0.10–0.68], P=0.006).

Conclusions

Hypercoagulability is associated with poor survival after stroke in patients with active cancer. Effective correction of hypercoagulability may play a protective role for survival in these patients.

Thrombosis in the setting of cancer

Venous thromboembolism (VTE) is a common cause of adverse outcomes in patients with cancer. The risk of VTE varies with cancer type, stage and grade, cancer therapy, and supportive care, as well as patient characteristics including age, ethnicity, and inherited and acquired comorbid conditions. VTE prophylaxis should be provided to all hospitalized cancer patients and high-risk outpatients. Low-molecular-weight heparin (LMWH) remains the first-line therapy for VTE in patients with active cancer. Anticoagulation should be continued as long as there is evidence of active disease or patients are receiving cancer treatment. The efficacy of direct oral anticoagulants in the treatment of cancer-associated thrombosis remains incompletely defined. Central venous catheter (CVC)-associated VTE should be treated with anticoagulation alone, unless the CVC is no longer required. Recent studies indicate that anticoagulation may be appropriate for patients with persistent thrombocytopenia or solid tumor brain metastases. Management of recurrent VTE includes the identification of the cause(s) of the recurrence and solutions targeted at addressing the potential precipitants.

Guidance for the practical management of the direct oral anticoagulants (DOACs) in VTE treatment

Venous thromboembolism (VTE) is a serious medical condition associated with significant morbidity and mortality, and an incidence that is expected to double in the next forty years. The advent of direct oral anticoagulants (DOACs) has catalyzed significant changes in the therapeutic landscape of VTE treatment. As such, it is imperative that clinicians become familiar with and appropriately implement new treatment paradigms. This manuscript, initiated by the Anticoagulation Forum, provides clinical guidance for VTE treatment with the DOACs. When possible, guidance statements are supported by existing published evidence and guidelines. In instances where evidence or guidelines are lacking, guidance statements represent the consensus opinion of all authors of this manuscript and are endorsed by the Board of Directors of the Anticoagulation Forum.

The authors of this manuscript first developed a list of pivotal practical questions related to real-world clinical scenarios involving the use of DOACs for VTE treatment. We then performed a PubMed search for topics and key words including, but not limited to, apixaban, antidote, bridging, cancer, care transitions, dabigatran, direct oral anticoagulant, deep vein thrombosis, edoxaban, interactions, measurement, perioperative, pregnancy, pulmonary embolism, reversal, rivaroxaban, switching, \thrombophilia, venous thromboembolism, and warfarin to answer these questions. Non- English publications and publications > 10 years old were excluded. In an effort to provide practical information about the use of DOACs for VTE treatment, answers to each question are provided in the form of guidance statements, with the intent of high utility and applicability for frontline clinicians across a multitude of care settings.

Management of venous thromboembolism: an update

Venous thromboembolism (VTE), which constitutes pulmonary embolism and deep vein thrombosis, is a common disorder associated with significant morbidity and mortality. Landmark trials have shown that direct oral anticoagulants (DOACs) are as effective as conventional anticoagulation with vitamin K antagonists (VKA) in prevention of VTE recurrence and associated with less bleeding. This has paved the way for the recently published guidelines to change their recommendations in favor of DOACs in acute and long-term treatment of VTE in patients without cancer. The recommended treatment of VTE in cancer patients remains low-molecular-weight heparin. The initial management of pulmonary embolism (PE) should be directed based on established risk stratification scores. Thrombolysis is an available option for patients with hemodynamically significant PE. Recent data suggests that low-risk patients with acute PE can safely be treated as outpatients if home circumstances are adequate. There is lack of support for use of inferior vena cava filters in patients on anticoagulation. This review describes the acute, long-term, and extended treatment of VTE and recent evidence on the management of sub-segmental PE.

Cancer-associated thrombosis in Asia

Thrombosis is a common complication in cancer patients. Although the major inherited risk factors for thrombophilia are different between Asians and Caucasians, the main acquired risk factors that are associated with the development of venous thromboembolism (VTE) in Asians appear to be similar to those for Caucasians. Malignancy is the most important acquired risk factor for VTE in Asians. Recent studies have shown that the incidence of VTE is significant in Asian patients with cancer, particularly those in an advanced stage. Cancer associated VTE is more severe and associated with higher morbidity and mortality. Unprovoked VTE is associated with an increased risk of subsequent cancer diagnosis. A number of international and national guidelines are available to provide guidance to healthcare providers to treat and prevent this serious complication based on best-available evidence. Identifying cancer patients at risk for VTE and use of appropriate thromboprophylaxis in these patients can potentially improve morbidity and mortality. Although direct oral anticoagulants (DOACs) may become an attractive treatment for cancer-associated VTE, further clinical trials are needed to evaluate the safety and efficacy of DOACs directly against LMWH in cancer patients.

Spotlight on real-world evidence for the treatment of DVT: XALIA

Venous thromboembolism (VTE), comprising both deep-vein thrombosis (DVT) and pulmonary embolism (PE), is a serious and common cardiovascular disease associated with the risk of chronic complications, recurrent VTE events and even death. The treatment landscape has, in recent years, seen a paradigm shift from the use of traditional anticoagulants (low-molecular-weight heparin [LMWH] overlapping with and followed by a vitamin K antagonist [VKA]) to non-VKA oral anticoagulants (NOACs). This class of agents, encompassing direct factor Xa inhibitors and direct thrombin inhibitors have shown non-inferior efficacy and better safety to standard of care in randomised controlled trials (RCTs). The direct, oral factor Xa inhibitor rivaroxaban was the first to be approved for treatment of acute DVT and PE and secondary prevention of recurrent VTE events based on data from EINSTEIN DVT and EINSTEIN PE, respectively. Real-world evidence now helps to further support data from RCTs, and also bridges the gap for physicians regarding any areas of clinical uncertainty that may not be addressed by RCTs. XA inhibition with rivaroxaban for Long-term and Initial Anticoagulation in venous thromboembolism (XALIA) was the first large, prospective, observational, real-world study that has investigated the safety and effectiveness profile of rivaroxaban in patients with DVT and PE associated with DVT in routine clinical practice. This article will present the key clinical outcomes from this important global non-interventional study, and will discuss remaining questions to be addressed in Phase IV studies.

Treatment of Venous Thromboembolism With New Anticoagulant Agents

Venous thromboembolism (VTE) is a common disease associated with high risk for recurrences, death, and late sequelae, accounting for substantial health care costs. Anticoagulant agents are the mainstay of treatment for deep vein thrombosis and pulmonary embolism. The recent availability of oral anticoagulant agents that can be administered in fixed doses, without laboratory monitoring and dose adjustment, is a landmark change in the treatment of VTE. In Phase III trials, rivaroxaban, apixaban, edoxaban (antifactor Xa agents), and dabigatran (an antithrombin agent) were noninferior and probably safer than conventional anticoagulation therapy (low-molecular-weight heparin followed by vitamin K antagonists). These favorable results were confirmed in specific patient subgroups, such as the elderly and fragile. However, some patients, such as those with cancer or with intermediate- to high-risk pulmonary embolism, were underrepresented in the Phase III trials. Further clinical research is required before new oral anticoagulant agents can be considered standard of care for the full spectrum of patients with VTE.

Use of Direct Oral Anticoagulants in Special Populations

Direct oral anticoagulants (DOACs) have been approved for the treatment of venous thromboembolism and atrial fibrillation based on randomized controlled trials (RCTs) of direct comparisons with vitamin K antagonists. Despite having more than 100,000 patients enrolled, safety and efficacy are debated in selected populations. Although DOACs are reviewed as a class of anticoagulant, pharmacokinetic differences exist such that different medications may be beneficial in distinct clinical settings. Synthesizing available evidence based on phase III RCTs, post hoc subgroup analyses, and pooled metaanalyses, this review provides an overview of DOACs and scrutinizes individual differences in their applications for the special populations.

Managing Extended Oral Anticoagulation After Unprovoked Venous Thromboembolism

Venous thromboembolism (VTE), which includes deep venous thrombosis and pulmonary embolism, is a major public health problem associated with increased morbidity and mortality. Despite the high recurrence risk associated with unprovoked VTE, extended anticoagulation remains controversial. Oral antithrombotic agents for extended VTE treatment comprise the vitamin K antagonists, aspirin, and the direct oral anticoagulants (also known as target-specific oral anticoagulants and formerly known as the new or novel oral anticoagulants) including rivaroxaban, dabigatran, apixaban, and edoxaban. The efficacy of these anticoagulants in reducing the risk of VTE recurrence (>80%-90% relative risk reduction) is offset by the risk of major bleeding that approaches 3% per year. Stratifying risks of recurrence and bleeding to identify patients at low, intermediate, or high risk and carefully considering the pharmacologic profile of the antithrombotic agents will help clinicians in choosing the optimal anticoagulant and duration and/or surveillance strategy. This review will discuss the current guidelines for extended VTE treatment, review the clinical trials involving the direct oral anticoagulants, and present the clinical considerations and concerns involving extended therapy.

Efficacy and Safety of Rivaroxaban in Patients with Venous Thromboembolism and Active Malignancy: A Single-Center Registry

OBJECTIVE

The purpose of this study is to evaluate the efficacy and safety of rivaroxaban in patients with venous thromboembolism and active malignancy, given the paucity of clinical data with the use of direct Xa inhibitors in this high-risk population.

PATIENTS AND METHODS

Consecutive patients treated with rivaroxaban for deep vein thrombosis or pulmonary embolism, enrolled into Mayo Thrombophilia Clinic Direct Oral Anticoagulants Registry between March 1, 2013, and April 30, 2015, were followed prospectively to evaluate the efficacy and safety of this therapy.

RESULTS

Of the 404 venous thromboembolism patients in the registry, 296 received rivaroxaban and had at least 3 months of follow-up. Of these, 118 (40%) had active malignancy (51% female, mean age 66 ± 10 years) and 178 had no cancer (47% female, mean age 55 ± 15 years). The 3 most common cancer locations were genitourinary (23.6%), gastrointestinal (20.3%), and lung (13.5%). There was no difference in venous thromboembolism recurrence between the malignant (3.3%) and the nonmalignant (2.8%) venous thromboembolism groups (P = .533). Borderline higher rates for major bleeding (P = .06) and nonmajor clinically relevant bleeding (P = .08) were observed in patients with cancer.

CONCLUSIONS

The "real world" effectiveness and safety of rivaroxaban is similar for venous thromboembolism patients with and without active malignancy.

[Venous thrombo-embolic disease in cancer. Low molecular weight heparin indications]

Cancer and venous thrombo-embolic disease (VTE) are closely related. Indeed, cancer can reveal VTE and VTE can be the first sign of cancer. Low molecular weight heparin (LWMH) is now the first line treatment in cancer patients. Compliance with marketing authorizations and guidelines are crucial for patient-centered decision-making. This work deals with the prescription of LWMH in patients who develop VTE during cancer in order to better recognize what should or should not be done. The patient's wishes must be taken into consideration when making the final therapeutic decision. The other treatments are discussed: vitamin K antagonists and direct oral anticoagulants (DOACs) may be useful.

Novel Oral Anticoagulants for Venous Thromboembolism with Special Emphasis on Risk of Hemorrhagic Complications and Reversal Agents

Warfarin was the only oral anticoagulant available for the treatment of venous thromboembolism for about half a century until the recent approval of novel oral agents dabigatran, rivoraxaban and apixaban. This presents new classes of medications less cumbersome to use. They do not require frequent laboratory monitoring or have nurmerous drug interactions. On the other hand it also poses a challenge to the physicians deciding which agent to use in specific patient populations, how to predict the bleeding risk compared to warfarin and between the different novel agents and how to manage bleeding with relatively recent discovery of few potential antidotes. This review summarizes the major trials that led to the approval of these agents and their exclusion criteria helping physicians understand which patient types might not benefit from these agents. It provides clinical pearls invaluable in everyday practice such as transitioning between traditional and novel anticoagulants, dose adjustments for high risk populations, drug interactions and cost analysis. Futhermore, the review provides direct comparisons with warfarin and indirect comparisons among the novel agents in terms of efficacy and bleeding risk narrating the numbers of patients with intracranial, gastrointestinal and fatal hemorrhages in each of the major trials. We hope that this review will help the physicians inform their patients about the benefits and risks of these agents and enable them to make an informed selection of the most appropriate anticoagulant.

Recurrent Venous Thromboembolism in Two Patients With Cancer Taking Rivaroxaban

Pharmacologic agents for the treatment and prevention of venous thromboembolism in the cancer patient population are limited. Currently, low-molecular-weight heparin is recommended by national consensus guidelines for this indication. Rivaroxaban, an oral factor Xa inhibitor, is Food and Drug Administration (FDA) approved for the treatment and prevention of venous thromboembolism and offers the convenience of oral fixed-dose regimens, no routine laboratory monitoring, and has few drug and dietary interactions; however, its use in patients with cancer has not been largely studied. We report 2 cases of recurrent venous thromboembolism in patients with active cancer on rivaroxaban therapy. The first case is a 64-year-old female admitted for recurrent pulmonary embolism, and the second case is a 70-year-old female admitted for recurrent deep vein thrombosis. Both patients were receiving rivaroxaban at the time of thromboembolic recurrence. These cases serve as a reminder to health-care providers that more safety and efficacy data in the cancer patient population are needed prior to using rivaroxaban for venous thromboembolism treatment.

Primary prevention and treatment of venous thromboembolic events in patients with gastrointestinal cancers - Review

Venous thromboembolism event (VTE) is a common and morbid complication in cancer patients. Patients with gastrointestinal cancers often suffer from symptomatic or incidental splanchnic vein thrombosis, impaired liver function and/or thrombocytopenia. These characteristics require a thorough risk/benefit evaluation for individual patients. Considering the risk factors for the development of VTE and bleeding events in addition to recent study results may be helpful for correct initiation of primary pharmacological prevention and treatment of cancer-associated thrombosis (CAT), preferably with low molecular weight heparins (LMWH). Whereas thromboprophylaxis is most often recommended in hospitalized surgical and non-surgical patients with malignancy, there is less agreement as to its duration. With regard to ambulatory cancer patients, the lack of robust data results in low grade recommendations against routine use of anticoagulant drugs. Anticoagulation with LMWH for the first months is the evidence-based treatment for acute CAT, but duration of secondary prevention and the drug of choice are unclear. Based on published guidelines and literature, this review will focus on prevention and treatment strategies of VTE in patients with gastrointestinal cancers.

Cancer-Associated Venous Thromboembolism

OPINION STATEMENT

Cancer patients are at high risk for venous thromboembolism (VTE) which is considered the second leading cause of death among this population. Both cancer and cancer treatment increase this risk. Since the risk of VTE is not the same in all cancer patients, it is important to understand what factors increase the risk of incident and the risk of recurrent VTE in this patient population. In an effort to combine multiple factors into a single risk stratification system, a scoring system for recurrent VTE risk in cancer patients has been developed and externally validated. While vitamin K antagonists (VKA) or the direct oral anticoagulants (DOACs) are first-line therapies for non-cancer-associated VTE treatment, low-molecular-weight heparin (LMWH) agents are the first-line anticoagulant for treatment of cancer-associated VTE. In this review, we discuss the epidemiology, pathophysiology, and risk stratification used in cancer-associated VTE. We also discuss the current therapies for cancer-associated VTE and the evidence supporting their use from the literature.

Antithrombotic Therapy for VTE Disease: CHEST Guideline and Expert Panel Report

BACKGROUND

We update recommendations on 12 topics that were in the 9th edition of these guidelines, and address 3 new topics.

METHODS

We generate strong (Grade 1) and weak (Grade 2) recommendations based on high- (Grade A), moderate- (Grade B), and low- (Grade C) quality evidence.

RESULTS

For VTE and no cancer, as long-term anticoagulant therapy, we suggest dabigatran (Grade 2B), rivaroxaban (Grade 2B), apixaban (Grade 2B), or edoxaban (Grade 2B) over vitamin K antagonist (VKA) therapy, and suggest VKA therapy over low-molecular-weight heparin (LMWH; Grade 2C). For VTE and cancer, we suggest LMWH over VKA (Grade 2B), dabigatran (Grade 2C), rivaroxaban (Grade 2C), apixaban (Grade 2C), or edoxaban (Grade 2C). We have not changed recommendations for who should stop anticoagulation at 3 months or receive extended therapy. For VTE treated with anticoagulants, we recommend against an inferior vena cava filter (Grade 1B). For DVT, we suggest not using compression stockings routinely to prevent PTS (Grade 2B). For subsegmental pulmonary embolism and no proximal DVT, we suggest clinical surveillance over anticoagulation with a low risk of recurrent VTE (Grade 2C), and anticoagulation over clinical surveillance with a high risk (Grade 2C). We suggest thrombolytic therapy for pulmonary embolism with hypotension (Grade 2B), and systemic therapy over catheter-directed thrombolysis (Grade 2C). For recurrent VTE on a non-LMWH anticoagulant, we suggest LMWH (Grade 2C); for recurrent VTE on LMWH, we suggest increasing the LMWH dose (Grade 2C).

CONCLUSIONS

Of 54 recommendations included in the 30 statements, 20 were strong and none was based on high-quality evidence, highlighting the need for further research.

The Role of New Oral Anticoagulants (NOACs) in Cancer Patients

New oral anticoagulants (NOACs) are likely to have a major impact in the next few years, changing clinical practice of anticoagulation therapy. Evidence on its efficacy and superiority to vitamin K antagonists (VKAs) in treating non-cancer patients have been reported in a few clinical trials. However, patients with cancer are complicated by the prothrombotic nature of the disease, need for potentially invasive surgery and interventions, and altered drug handling. This chapter examines the available evidence and guidelines on the use of NOAC in patients with cancer.

Critical Review and Update on the Treatment of Acute and Chronic Pulmonary Embolism

Pulmonary embolism (PE), can be life-threatening without rapid appropriate therapy and often leads to chronic disease and disability. The ambiguity of symptoms makes PE difficult to diagnose, and available imaging strategies have their limitations. Treatment options for acute PE include fibrinolytics, surgical embolectomy, catheter-directed treatment, or vena cava filter placement as well as traditional parenteral anticoagulants, used alone or as a bridge to a vitamin K antagonist (VKA). The direct oral anticoagulants (DOACs) rivaroxaban and apixaban allow for single drug therapy, eliminating the need for initial parenteral anticoagulation, while dabigatran and edoxaban are initiated after a short course of parenteral therapy. The DOACs serve as a viable alternative to warfarin for chronic management for PE. Pulmonary embolism provoked from transient risk factors often requires a short-term course of anticoagulation (3 months). Unprovoked events, and those that occur in the presence of continuing risk factors such as cancer, or clinical markers such as residual vein thrombosis and elevated d-dimers can predict a higher risk of recurrent events and warrant extended anticoagulation. This review evaluates current recommendations for the treatment of PE, including dosing strategies, duration of therapy, and special populations such as renal impairment, malignancy, and obesity.

Venous Thromboembolism in Patients Diagnosed With Lung Cancer

PURPOSE

Considering the high prevalence of lung cancer, our purpose was to summarize the existing literature to identify the several factors that contribute to the increased risk of venous thromboembolism (VTE) in patients with lung cancer and to analyze the current recommendations for thromboprophylaxis and treatment of VTE in those patients.

METHODS

We searched the Medline and EMBASE databases from February 1985 to February 2014 to identify retrospective and prospective randomized controlled studies that investigate one or more risk factors for VTEs in patients with lung cancer.

RESULTS

A VTE is a major complication for patients diagnosed with lung cancer. The risk factors for VTE events in patients with lung cancer consist of cancer-related (histological type and stage of cancer), treatment-related (surgery, chemotherapy, angiogenic agents, and supportive care agents), and patient-related factors (comorbidities, immobility, performance status, and prior thrombosis). Low-molecular-weight heparins are recommended for long-term treatment of cancer-associated thrombosis. Duration of anticoagulant therapy beyond 6 months should be based on individual clinical evaluation. Thromboprophylaxis for patients with lung cancer during hospitalization and immediate postoperative period is well established.

CONCLUSIONS

Efforts to assess thrombotic risk in patients with lung cancer may improve therapeutic and preventive strategies in the future, with final goal to minimize the burden and consequences of thrombotic events in patients with lung cancer.

Pros and cons of new oral anticoagulants in the treatment of venous thromboembolism in patients with cancer

Patients with cancer account for 20 % of cases of venous thromboembolism (VTE). Cancer patients are at increased risk for VTE during the entire course of their disease, also in absence of traditional VTE risk factors. Furthermore, patients with VTE and cancer have an estimated risk of bleeding of 15-20 % per year while on anticoagulant treatment. For these reasons, treatment of acute VTE in patients with cancer remains a clinical challenge. In clinical studies, which included about 27,000 patients, new oral anticoagulants (NOACs) have been shown to be as effective and safe as conventional anticoagulation (heparin given with and followed by vitamin K antagonists) for the treatment of VTE. In these studies, 1227 patients with active cancer were enrolled. Preliminary results of subgroup analyses and meta-analyses of randomized clinical trials suggest that NOACs could represent an alternative to conventional anticoagulation in patients with active cancer. Further "ad hoc" studies evaluating the clinical benefit of treatment with NOACs in patients with VTE and cancer are needed.

Update on Edoxaban for the Prevention and Treatment of Thromboembolism: Clinical Applications Based on Current Evidence

Vitamin K antagonists (VKA) and heparins have been utilized for the prevention and treatment of thromboembolism (arterial and venous) for decades. Targeting and inhibiting specific coagulation factors have led to new discoveries in the pharmacotherapy of thromboembolism management. These targeted anticoagulants are known as direct oral anticoagulants (DOACs). Two pharmacologically distinct classes of targeted agents are dabigatran etexilate (Direct Thrombin Inhibitor (DTI)) and rivaroxaban, apixaban, and edoxaban (direct oral factor Xa inhibitors (OFXaIs)). Emerging evidence from the clinical trials has shown that DOACs are noninferior to VKA or low-molecular-weight heparins in the prevention and treatment of thromboembolism. This review examines the role of edoxaban, a recently approved OFXaI, in the prevention and treatment of thromboembolism based on the available published literature. The management of edoxaban in the perioperative setting, reversibility in bleeding cases, its role in cancer patients, the relevance of drug-drug interactions, patient satisfaction, financial impacts, and patient education will be discussed.

L-asparaginase and venous thromboembolism in acute lymphocytic leukemia

The occurrence of venous thromboembolism (VTE) in acute lymphocytic leukemia patients receiving L-asparaginase therapy may cause significant morbidity, neurological sequela and possibly worse outcomes. The prophylactic use of antithrombin infusion (to keep antithrombin activity >60%) or low molecular weight heparin (LMWH) may reduce the risk of VTE. The decision to continue L-asparaginase therapy after the development of VTE should be based on anticipated benefits, severity of VTE and the ability to continue therapeutic anticoagulation. In patients receiving asparaginase rechallenge, the use of therapeutic LMWH, monitoring of anti-Xa level and antithrombin level are important. Novel oral anticoagulants are not dependent on antithrombin level, hence offer theoretical advantages over LMWH for the prevention and therapy of asparaginase-related VTE.

Differential benefit risk assessment of DOACs in the treatment of venous thromboembolism: focus on dabigatran

Venous thromboembolism includes deep vein thrombosis and pulmonary embolism and is a serious medical condition that requires anticoagulation as part of treatment. Currently, standard therapy consists of parenteral anticoagulation followed by a vitamin K antagonist (VKA). The pharmacokinetic and pharmacodynamic profiles of the direct oral anticoagulants (DOACs) differ from VKAs, which overcome some of the limitations of VKAs and have practical implications on their use in clinical situations. Dabigatran is a prodrug that undergoes primarily renal elimination and does not affect cytochrome P450 enzymes. Assays to quantify the degree of anticoagulation and the therapeutic level of DOAC are either unavailable for routine clinical use or require specific calibration. Routine monitoring of DOACs is not recommended at this time. Dabigatran, rivaroxaban, and apixaban are DOACs that have been studied for treatment of venous thromboembolism. Clinical trials comparing DOACs with standard therapy have shown them to be non-inferior for acute and extended therapy. Each DOAC has a unique benefit and harm profile that should be considered prior to use. The distinguishing characteristics of dabigatran include a requirement of parenteral anticoagulation prior to acute treatment, clinical trial results comparing it with a VKA for extended treatment, association with upper gastrointestinal adverse events, and increased risk of gastrointestinal bleed. Rivaroxaban is the only DOAC that has once-daily dosing while apixaban is the only DOAC that has lower risk of overall, major, and gastrointestinal bleeding compared with VKA. A common drawback of DOACs is the lack of an available reversal agent. Clinical trials of reversal agents are ongoing and one application for approval has been submitted to the US Food and Drug Administration. Selection of a DOAC for acute and extended therapy requires a shared decision-making approach that includes a comprehensive assessment of the benefits and harms of each individual DOAC.

Practical management of bleeding in patients receiving non-vitamin K antagonist oral anticoagulants

Non-vitamin K antagonist oral anticoagulants (NOACs) are increasingly used in the prevention and treatment of venous thromboembolism and in the prevention of stroke in patients with non-valvular atrial fibrillation. In phase III clinical trials and meta-analyses, the NOACs were at least as effective as vitamin K antagonists (VKAs) and were associated with a similar or lower incidence of major bleeding, including consistent and significant decreases in intracranial bleeding, although with an increase in gastrointestinal bleeding for some agents compared with VKAs. Subsequent real-world evidence supports these outcomes. Despite this, physicians have concerns about serious bleeding or emergencies because there are no specific reversal agents for the NOACs. However, in clinical trials, patients receiving NOACs generally had similar or better outcomes after these events than those taking VKAs. As with any bleeding, anticoagulant-related bleeding should first be stratified according to severity and location; risk can be minimised by ongoing assessment. Management protocols for NOAC-related bleeding are similar to those for VKAs but should take into account the pharmacological profile of the specific drug. Because of their short half-lives, NOAC-related mild bleeding can often be controlled by temporarily withholding treatment. More severe bleeding requires standard escalating haemodynamic support measures, and non-specific reversal agents can be considered in life-threatening situations, based on limited clinical data. Specific and rapid reversal agents are not currently available for any oral anticoagulant and restoration of coagulation may not necessarily lead to better outcomes. Nevertheless, specific NOAC reversal agents are in development and show promise in healthy volunteers.