Management of venous thromboembolism in cancer patients and the role of the new oral anticoagulants

Successful Multimodal Treatment of Pancreatic Cancer With Extensive Superior Mesenteric Vein Thrombosis Utilizing Chemotherapy Combined With Direct Oral Anticoagulant

It is well known that portal vein thrombosis (PVT) sometimes occurs in pancreatic cancer (PC). However, no effective treatment plan for PVT in PC patients has yet been proposed. We experienced a successfully treated case of borderline resectable pancreatic cancer (PC-BR) with extensive superior mesenteric vein thrombosis utilizing intensive chemotherapy combined with direct oral anticoagulant. The thrombus disappeared and the tumor shrank, enabling curative surgery, and long-term survival for more than five years has been achieved. We report this successful case that we experienced as an option for the treatment of PC-BR with PVT in the future era when multimodal treatment is important.

Arteriovenous thrombotic events in a patient with advanced lung cancer following bevacizumab plus chemotherapy: A case report

BACKGROUND

In driver gene-negative non-small cell lung cancer patients who relapse following radical resection, combination chemotherapy using bevacizumab and platinum-based dual drugs is known to increase both progression-free and overall survival. Treatment initially includes bevacizumab, and if patients are able to tolerate it, bevacizumab can continue to be utilized until disease progression. Bevacizumab is a recombinant humanized monoclonal neutralizing antibody that acts against vascular endothelial growth factor (VEGF). Various anti-VEGF monoclonal antibodies, such as bevacizumab, can increase the risk of arterial thromboembolism. Current data indicate that VEGF-targeted treatment does not significantly increase the risk of venous thromboembolism events, except for bevacizumab.

CASE SUMMARY

A 55-year-old man underwent radical resection for cancer of the right lung. Six months following surgery, multiple metastases were observed in his left lung. Subsequently, six cycles of bevacizumab combined with pemetrexed/carboplatin chemotherapy was given. Efficacy evaluation continued to be partial relief according to RECIST 1.1 standards, and no noticeable adverse reactions were noted. After three cycles of maintenance therapy using a combination of bevacizumab and pemetrexed, the patient developed dizziness and dyspnea. The patient was diagnosed with acute cerebral infarction and pulmonary embolism following head magnetic resonance imaging, computed tomography (CT) angiography, and chest enhanced CT. Although the patient received low-molecular-weight heparin anticoagulation and other treatment, the patient eventually died of respiratory failure 1 mo later. This case report may offer some insight into fatal arteriovenous embolism, which has not been previously reported.

CONCLUSION

Bevacizumab combined with chemotherapy may also increase the risk of arteriovenous thromboembolism. Accordingly, patients who receive angiogenesis inhibitor therapy should be carefully selected. Furthermore, close monitoring and timely intervention are necessary in order to reduce the risk of such toxicities.

A Systematic Review of the Guidelines on Venous Thromboembolism Prophylaxis in Gynecologic Oncology

(1) Background: This review aimed to summarize the indications for venous thromboembolic (VTE) events' prophylaxis in a gynecological cancer population, according to the most recent guidelines. (2) Methods: A systematic review of the guidelines in PubMed, SCOPUS, Web of Science, EMBASE, and CINHAL regarding VTE prevention in gynecological cancer patients was conducted according to PRISMA criteria. We compared the recommendations given by oncological and hematological societies regarding VTE prevention in gynecological cancer patients published from January 2010 through March 2021. We searched for the following keywords: "venous thromboembolism prevention", "cancer", and "guidelines". The AGREE II checklist was used to critically analyze the guidelines' quality. (3) Results: There were 1003 documents available; 14 met the inclusion criteria, 5 were excluded and, eventually, the guidelines of 10 societies were evaluated. (4) Conclusions: The guidelines agree that low-molecular-weight heparin (LMWH) and fondaparinux achieve better results in VTE prevention in gynecological cancer patients. Direct oral anticoagulants (DOACs) can be used to prevent VTE in outpatients and high-risk medical patients after discharge. VTE risk scores should be applied to all oncological patients to identify those who would benefit from a prevention program. More attention should be paid to mechanical prophylactic methods due to the high bleeding risk of gynecological cancer patients.

Efficacy and Safety of Edoxaban in Cancer-Associated Venous Thromboembolism: A Real World Retrospective Study

Introduction  Few data exist on the use of edoxaban in cancer-associated venous thromboembolism (VTE) outside of clinical trials. Aim of this study was to evaluate the characteristics and outcomes of these patients in a real world clinical setting. Methods  We retrospectively analyzed the characteristics of patients with cancer-associated VTE who were prescribed edoxaban. Follow-up at 3, 6, and 12 months was performed: VTE recurrences, bleedings, mortality, cancer progression and treatment, edoxaban interruption and its reason were assessed. Results  Fifty-four patients, 38 females (70.4%), mean age 71 ± 14 years, were enrolled. In 38 patients (70.4%), the episode of VTE was the first one, in 28 (51.8%) it was an isolated deep vein thrombosis (DVT), in 13 (24.1%) a pulmonary embolism (PE) associated with DVT, in 13 (24.1%) an isolated PE. Median time between cancer and VTE diagnosis was 6 (interquartile range [IQR] 2-47) months. Median time between VTE diagnosis and edoxaban prescription was 36 (IQR 7-117) days. At 3, 6, and 12 months the incidence of all-cause mortality was 16.6, 22.2, and 38.8%, that of VTE recurrence 1.8, 1.8, and 3.7%, and that of major bleeding 7.4, 9.2, and 12.9%, respectively. No bleeding was fatal. Of the 33 patients alive at 12 months, 32 (96.9%) were still on edoxaban therapy, in seven (21.2%) cancer was in progression. Conclusion  Our study, conducted on a real world population of patients with cancer-associated VTE, confirms the results of randomized controlled clinical trials, and supports the use of edoxaban as effective and safe treatment in this context.

Cancer-associated venous thromboembolism: Treatment and prevention with rivaroxaban

Cancer-associated venous thromboembolism (VTE) is a frequent, potentially life-threatening event that complicates cancer management. Anticoagulants are the cornerstone of therapy for the treatment and prevention of cancer-associated thrombosis (CAT); factor Xa-inhibiting direct oral anticoagulants (DOACs; apixaban, edoxaban, and rivaroxaban), which have long been recommended for the treatment of VTE in patients without cancer, have been investigated in this setting. The first randomized comparisons of DOACs against low-molecular-weight heparin for the treatment of CAT indicated that DOACs are efficacious in this setting, with findings reflected in recent updates to published guidance on CAT treatment. However, the higher risk of bleeding events (particularly in the gastrointestinal tract) with DOACs highlights the need for appropriate patient selection. Further insights will be gained from additional studies that are ongoing or awaiting publication. The efficacy and safety of DOAC thromboprophylaxis in ambulatory patients with cancer at a high risk of VTE have also been assessed in placebo-controlled randomized controlled trials of apixaban and rivaroxaban. Both studies showed efficacy benefits with DOACs, but both studies also showed a nonsignificant increase in major bleeding events while on treatment. This review summarizes the evidence base for rivaroxaban use in CAT, the patient profile potentially most suited to DOAC use, and ongoing controversies under investigation. We also describe ongoing studies from the CALLISTO (Cancer Associated thrombosis-expLoring soLutions for patients through Treatment and Prevention with RivarOxaban) program, which comprises several randomized clinical trials and real-world evidence studies, including investigator-initiated research.

The anticoagulants rivaroxaban and low molecular weight heparin prevent PICC-related upper extremity venous thrombosis in cancer patients

Peripherally inserted central catheter (PICC) is often applied in chemotherapy patients and commonly causes upper extremity venous thrombosis (UEVT), which should be prevented.To assess the preventive effects of the anticoagulants rivaroxaban and low molecular weight heparin (LMWH) on UEVT in patients receiving chemotherapy through PICCs.A total of 423 chemotherapy patients with continuous PICC use between January 2014 and June 2015 at the Oncology Department of Dongying People's Hospital were divided into 3 groups: rivaroxaban (10 mg/day, orally), LMWH (Enoxaparine, 4000 anti-Xa IU/day, subcutaneous injection), and control (no anticoagulant). UEVT incidence and other complications during PICC use were observed and recorded.The rivaroxaban, LMWH, and control groups included 138 (79 males; 54.9 ± 11.0 years), 144 (76 males; 56.0 ± 10.9 years), and 141 (71 males; 53.3 ± 10.9 years) patients, (P = .402 and P = .623 for age and sex respectively). There were no differences in cancer location (P = .628), PICC implantation site (P > .05), body mass index (BMI) (P = .434), blood pressure (all P > .05), blood lipids (5 laboratory parameters included, all P > .5), smoking (P = .138), history of lower limb venous thrombosis (P = .082), and 10 other associated comorbidities (all P > .5). Twenty-nine patients withdrew from the study (5 from the rivaroxaban, 12 from the LMWH, and 12 from the control groups, respectively), and 394 patients were analyzed. There were significant differences in the rivaroxaban group and the LMWH group compared to the control group (P = .010 and P = .009, respectively), but no significant difference was observed between the rivaroxaban group and the LMWH group (P = .743).Anticoagulants such as rivaroxaban and LMWH may reduce the incidence of PICC-related UEVT in patients receiving chemotherapy.

Direct Oral Anticoagulant Drugs: On the Treatment of Cancer-Related Venous Thromboembolism and their Potential Anti-Neoplastic Effect

Cancer patients develop a hypercoagulable state with a four- to seven-fold higher thromboembolic risk compared to non-cancer patients. Thromboembolic events can precede the diagnosis of cancer, but they more often occur at diagnosis or during treatment. After malignancy itself, they represent the second cause of death. Low molecular weight heparins are the backbone of the treatment of cancer-associated thromboembolism. This treatment paradigm is possibly changing, as direct oral anticoagulants (DOACs) may prove to be an alternative therapeutic option. The currently available DOACs were approved during the first and second decades of the 21st century for various clinical indications. Three molecules (apixaban, edoxaban and rivaroxaban) are targeting the activated factor X and one (dabigatran) is directed against the activated factor II, thrombin. The major trials analyzed the effect of these agents in the general population, with only a small proportion of cancer patients. Two published and several ongoing studies are specifically investigating the use of DOACs in cancer-associated thromboembolism. This article will review the current available literature on the use of DOACs in cancer patients. Furthermore, we will discuss published data suggesting potential anti-cancer actions exerted by non-anticoagulant effects of DOACs. As soon as more prospective data becomes available, DOACs are likely to be considered as a potential new therapeutic option in the armamentarium for patients suffering of cancer-associated thromboembolism.

COSIMO - patients with active cancer changing to rivaroxaban for the treatment and prevention of recurrent venous thromboembolism: a non-interventional study

BACKGROUND

Around 20% of venous thromboembolism (VTE) cases occur in patients with cancer. Current guidelines recommend low molecular weight heparin (LMWH) as the preferred anticoagulant for VTE treatment. However, some guidelines state that vitamin K antagonists (VKAs) and direct oral anticoagulants (DOACs) are acceptable alternatives for long-term therapy in some patients if LMWHs are not available. LMWHs and VKAs have a number of drawbacks that can increase the burden on patients. DOACs, such as rivaroxaban, can ameliorate some burdens and may offer an opportunity to increase patient satisfaction and health-related quality of life (HRQoL). The Cancer-associated thrOmboSIs - patient-reported outcoMes with rivarOxaban (COSIMO) study is designed to provide real-world information on treatment satisfaction in patients with active cancer who switch from LMWH or VKA to rivaroxaban for the treatment of acute VTE or to prevent recurrent VTE.

METHODS

COSIMO is a prospective, non-interventional, single-arm cohort study that aims to recruit 500 patients in Europe, Canada and Australia. Adults with active cancer who are switching to rivaroxaban having received LMWH/VKA for the treatment and secondary prevention of recurrent VTE for at least the previous 4 weeks are eligible. Patients will be followed for 6 months. The primary outcome is treatment satisfaction assessed as change in the Anti-Clot Treatment Scale (ACTS) Burdens score at week 4 after enrolment compared with baseline. Secondary outcomes include treatment preferences, measured using a discrete choice experiment, change in ACTS Burdens score at months 3 and 6, and change in HRQoL (assessed using the Functional Assessment of Chronic Illness Therapy - Fatigue questionnaire). COSIMO will collect data on patients' medical history, patterns of anticoagulant use and incidence of bleeding and thromboembolic events. Study recruitment started in autumn 2016.

CONCLUSIONS

COSIMO will provide information on outcomes associated with switching from LMWH or VKA therapy to rivaroxaban for the treatment or secondary prevention of cancer-associated thrombosis in a real-life setting. The key goal is to assess whether there is a change in patient-reported treatment satisfaction. In addition, COSIMO will facilitate the evaluation of the safety and effectiveness of rivaroxaban in preventing recurrent VTE in this patient population.

TRIAL REGISTRATION

NCT02742623. Registered 19 April 2016.

Visceral Thromboses in Pancreas Adenocarcinoma: Systematic Review

Within gastrointestinal malignancies, primary hepatocellular carcinoma and pancreatic ductal adenocarcinoma (PDAC) are frequently associated with visceral thromboses (VT). Thrombus formation in the portal (PVT), mesenteric (MVT), or splenic vein (SVT) system leads to portal hypertension and intestinal ischemia. VT in PDAC may convey a risk of increased distal thrombosis and poses therapeutic uncertainty regarding the role of anticoagulation. An increasing number of reports describe VT associated with PDAC. It is possible that early diagnosis of these events may help reduce morbidity and speculatively improve oncologic outcomes. To perform a systematic review to study PVT, MVT, and SVT associated with PDAC, and to provide a comprehensive review. Medline/PubMed, Embase, Web of Science, Scopus, and the Cochrane Library. Data Extraction and Assessment: Two blinded independent observers extracted and assessed the studies for diagnosis of PVT, MVT, and SVT in PDAC. Studies were restricted to English-language literature published between 2007 and 2016. Eleven articles were identified. Five case reports and 7 retrospective studies were found, with a total of 127 patients meeting the inclusion criteria. The mean age at diagnosis was 64 years. PVT was found in 35% (n = 46), SVT in 52% (n = 65), and MVT in 13% (n = 15). Mean follow-up time was 26 months. Only 3 of the selected articles studied the impact of anticoagulation in VT. All patients with nonvisceral thrombosis (eg, deep-vein thrombosis, pulmonary emboli) were therapeutically treated; in contrast, patients with VT only rarely received treatment. VT in PDAC is a frequent finding at diagnosis or during disease progression. Evidence to guide treatment choices is limited, and current management is based on inferred experience from nononcologic settings. Anticoagulation appears to be safe in VT, with most of the large studies recommending a careful assessment for patients at a high risk of bleeding.

What have we learned from real-world NOAC studies in venous thromboembolism treatment?

Venous thromboembolism (VTE) remains a substantial clinical and health-economic burden worldwide and effective anticoagulant treatment is necessary immediately after VTE is suspected to reduce short- and long-term VTE related morbidity and mortality. For decades, low molecular weight heparin (LMWH), fondaparinux and Vitamin K antagonists (VKAs) have been the standard of anticoagulant therapy for VTE patients but these treatment options had clinically relevant drawbacks and limitations. The introduction of non-VKA oral anticoagulants (NOACs) that specifically inhibit either thrombin or factor Xa have resolved many of these drawbacks because these new compounds exhibit a rapid onset and offset of action, fewer food and drug interactions and a predictable anticoagulant effect. All NOACs have successfully completed their respective phase-III trial programs consisting of many large randomized controlled trials, leading to approval for acute VTE treatment around the world. Nevertheless, their introduction into daily care practice is challenging and a careful evaluation of the effectiveness and safety of NOACs in less selected cohorts outside carefully monitored clinical trials is essential. This review introduces the different types of real-world evidence (RWE) and explores the available data for VTE treatment with NOACs, based on a literature search using the key words "venous thromboembolism" or "VTE" in combination with "NOAC", "DOAC", "apixaban", "dabigatran", "edoxaban" and "rivaroxaban" on June 30; 2017, followed by data extraction from studies that reported real-world outcome data for VTE treatment with NOACs, although available evidence is almost exclusively limited to rivaroxaban.

Low molecular weight heparin versus rivaroxaban in the treatment of venous thromboembolism in gastrointestinal malignancies

: Due to their ease of use, the direct oral anticoagulants (DOACs) are an attractive treatment option for cancer-associated venous thromboembolism (VTE) and have been readily adopted by many clinicians. A recent published study comparing a DOAC (edoxaban) to the current standard-of-care low molecular weight heparin dalteparin for the treatment of cancer-associated thrombosis showed that edoxaban was noninferior to dalteparin for recurrent VTE, but the risk of major bleeding was higher. We present three patients with high-risk gastrointestinal malignancies complicated by cancer-associated VTE with progression of thrombosis while treated with the oral direct Xa inhibitor rivaroxaban. Upon switching therapy to low molecular weight heparin, we found that these patients had clinical and radiologic improvement of VTE. More studies are needed to evaluate the efficacy of rivaroxaban in high-risk gastrointestinal-VTE. We suggest that in some patients, DOACs may not be sufficient for the treatment of VTEs related to high-risk gastrointestinal malignancies.

Venous Thromboembolism in Gynecological Malignancy

Objective

Venous thromboembolism (VTE) is a recognized complication of gynecological malignancy and represents a leading cause of morbidity and mortality in these patients. The review aimed to discuss the incidence, risk factors, and clinical presentation of VTE before examining the literature on the diagnosis, prevention, and management in the context of uterine, cervical, ovarian, and vulval cancers.

Methods/Materials

A literature search was performed using Ovid Medline and Embase with the following words: “gynecological malignancy,” “pelvic tumor,” “venous thromboembolism,” “deep vein thrombosis” and “pulmonary embolism.”

Results

The incidence of VTE in patients with gynecological malignancy ranged between 3% and 25% and was affected by several patient and tumor factors. Duplex ultrasonography is currently the first-line imaging modality for deep venous thrombosis with sensitivity and specificity of up to 95% and 100%, respectively. Low-molecular-weight heparin is currently the VTE prophylaxis and treatment of choice for patients with gynecological malignancy, although warfarin and unfractionated heparin play a role in selected circumstances. The relatively new direct oral anticoagulants including factor Xa inhibitors and direct thrombin inhibitors are increasingly being used, although further evaluations are required, particularly in cancer patients. Catheter-directed thrombolysis and percutaneous mechanical and surgical thrombectomy may have a role in treating patients with severe symptomatic iliocaval or iliofemoral deep venous thrombosis. Overall, VTE is a poor prognosis marker in patients with gynecological malignancy.

Conclusions

Gynecological malignancy–associated VTE is associated with significant morbidity, contributing to a large number of life years lost. Although promising new therapies are emerging, a 2-pronged approach is required to simultaneously target cancer-specific management and predict early on those who are likely to be affected. In the meantime, clinicians should continue to combine current guidelines with a multidisciplinary team approach to ensure that these complex patients receive the best evidence-based and compassionate care.

Continuation of low-molecular-weight heparin treatment for cancer-related venous thromboembolism: a prospective cohort study in daily clinical practice

Essentials Low-molecular-weight heparin (LMWH) injections for venous thromboembolism (VTE) may be burdensome. Patients with active cancer and confirmed VTE were included to evaluate LMWH continuation. The cumulative incidence of discontinuation was 21% after a median period of 90 days. One out of five patients discontinued LMWH injections because of side effects.

SUMMARY

Background Current guidelines recommend low-molecular-weight heparin (LMWH) monotherapy for 3-6 months as the first-line treatment for cancer-associated venous thromboembolism (VTE). However, although daily administration of LMWH injections over a course of several months may be burdensome, the number of patients who stop treatment because of LMWH side-effects is unknown. Objectives To evaluate the continuation rate and complications of daily LMWH injections in patients with cancer-associated VTE. Methods Consecutive patients with active cancer and objectively confirmed symptomatic proximal deep vein thrombosis and/or pulmonary embolism, treated at three Dutch hospitals and one Spanish hospital, were included to evaluate continuation LMWH therapy during LMWH treatment. Patients were excluded when they received other anticoagulants, were lost to follow-up, or experienced a venous catheter-associated thrombosis. Results A total of 372 patients were analyzed during LMWH treatment for a maximum of 180 days. The cumulative incidence of discontinuation was 21% (95% confidence interval [CI] 17-25) after a median period of 90 days (interquartile range 60-120 days). Only female sex was found to be significantly associated with premature LMWH discontinuation (odds ratio 1.6; 95% CI 1.03-2.5). Thirty patients (8.1%) developed recurrent VTE, 30 patients (8.3%) suffered a major bleed, and 106 patients (28%) died. Conclusion Our study reveals that one of five patients with cancer-associated VTE stopped LMWH injections because of side-effects. This finding provides relevant background information for current clinical trials investigating the efficacy and safety of direct oral anticoagulants as compared with LMWH.

Widely Used Types and Clinical Applications of D-Dimer Assay

D-dimers are formed by the breakdown of fibrinogen and fibrin during fibrinolysis. D-dimer analysis is critical for the diagnosis of deep vein thrombosis, pulmonary embolism, and disseminated intravascular coagulation. Modern assays for D-dimer are monoclonal antibody based. The enzyme-linked immunosorbent assay (ELISA) is the reference method for D-dimer analysis in the central clinical laboratory, but is time consuming to perform. Recently, a number of rapid, point-of-care D-dimer assays have been developed for acute care settings that utilize a variety of methodologies. In view of the diversity of D-dimer assays used in central laboratory and point-of-care settings, several caveats must be taken to assure the proper interpretation and clinical application of the results. These include consideration of preanalytical variables and interfering substances, as well as patient drug therapy and underlying disease. D-dimer assays should also be validated in clinical studies, have established cut-off values, and reported according to the reagent manufacturers recommendations.

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.

The polyphosphate-factor XII pathway drives coagulation in prostate cancer-associated thrombosis

Cancer is a leading cause of thrombosis. We identify a new procoagulant mechanism that contributes to thromboembolism in prostate cancer and allows for safe anticoagulation therapy development. Prostate cancer-mediated procoagulant activity was reduced in plasma in the absence of factor XII or its substrate of the intrinsic coagulation pathway factor XI. Prostate cancer cells and secreted prostasomes expose long chain polyphosphate on their surface that colocalized with active factor XII and initiated coagulation in a factor XII-dependent manner. Polyphosphate content correlated with the procoagulant activity of prostasomes. Inherited deficiency in factor XI or XII or high-molecular-weight kininogen, but not plasma kallikrein, protected mice from prostasome-induced lethal pulmonary embolism. Targeting polyphosphate or factor XII conferred resistance to prostate cancer-driven thrombosis in mice, without increasing bleeding. Inhibition of factor XII with recombinant 3F7 antibody reduced the increased prostasome-mediated procoagulant activity in patient plasma. The data illustrate a critical role for polyphosphate/factor XII-triggered coagulation in prostate cancer-associated thrombosis with implications for anticoagulation without therapy-associated bleeding in malignancies.

The new direct oral anticoagulants in special indications: rationale and preliminary data in cancer, mechanical heart valves, anti-phospholipid syndrome, and heparin-induced thrombocytopenia and beyond

The present review will briefly summarize the interplay between coagulation and inflammation, highlighting possible effects of direct inhibition of factor Xa and thrombin beyond anticoagulation. Additionally, the rationale for the use of the new direct oral anticoagulants (DOACs) for indications such as cancer-associated venous thromboembolism (CAT), mechanical heart valves, thrombotic anti-phospholipid syndrome (APS), and heparin-induced thrombocytopenia (HIT) will be explored. Published data on patients with cancer or mechanical heart valves treated with DOAC will be discussed, as well as planned studies in APS and HIT. Although at the present time published evidence is insufficient for recommending DOAC in the above-mentioned indications, there are good arguments in favor of clinical trials investigating their efficacy in these contexts. Direct inhibition of factor Xa or thrombin may reveal interesting effects beyond anticoagulation as well.