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

The Role of Direct Oral Anticoagulants in the Treatment of Cancer-Associated Venous Thromboembolism: Review by Middle East and North African Experts

Venous thromboembolism is a leading cause of morbidity and mortality in patients with active cancer who require anticoagulation treatment. Choice of anticoagulant is based on careful balancing of the risks and benefits of available classes of treatment: vitamin K antagonists, low-molecular-weight heparin (LMWH), and direct oral anticoagulants (DOACs). Results from randomized controlled trials have shown the consistent efficacy of DOACs versus LMWH in the treatment of cancer-associated venous thromboembolism (VTE). However, increased major gastrointestinal bleeding was observed for edoxaban and rivaroxaban, but not apixaban, compared with LMWH dalteparin. Most guidelines recommend DOACs for the treatment of cancer-associated VTE in patients without gastrointestinal or genitourinary cancer, and with considerations for renal impairment and drug-drug interactions. These updates represent a major paradigm shift for clinicians in the Middle East and North Africa. The decision to prescribe a DOAC for a patient with cancer is not always straightforward, particularly in challenging subgroups of patients with an increased risk of bleeding. In patients with gastrointestinal malignancies who are at high risk of major gastrointestinal bleeds, apixaban may be the preferred DOAC; however, caution should be exercised if patients have upper or unresected lower gastrointestinal tumors. In patients with gastrointestinal malignancies and upper or unresected lower gastrointestinal tumors, LMWH may be preferred. Vitamin K antagonists should be used only when DOACs and LMWH are unavailable or unsuitable. In this review, we discuss the overall evidence for DOACs in the treatment of cancer-associated VTE and provide treatment suggestions for challenging subgroups of patients with cancer associated VTE.

[Venous thromboembolism: risk factors and prophylaxis]

Venous thromboembolism is an important complication in tumour patients as it occurs frequently in these patients and causes relevant morbidity. The risk of thromboembolic complications in tumour patients is 3-9 times higher than in non-tumour patients and is the second most common cause of death in tumour patients. The risk of thrombosis depends on tumour-induced coagulopathy and on individual factors, type and stage of cancer, time since cancer diagnosis as well as type of systemic cancer therapy. Thromboprophylaxis in tumour patients is effective but can be associated with increased bleeding. Even though there are currently no dedicated recommendations for individual tumour entities, international guidelines recommend prophylactic measures in high-risk patients. A thrombosis risk of >8-10% can be considered an indication for thromboprophylaxis, which is indicated by a Khorana score ≥2, and should be calculated individually using nomograms. In particular, patients with a low risk of bleeding should receive thromboprophylaxis. Risk factors and symptoms of a thromboembolic event should also be intensively discussed with the patient and materials for patient information should be handed out.

Risk and Timing of Venous Thromboembolism After Surgery for Lung Cancer: A Nationwide Cohort Study

BACKGROUND

Venous thromboembolism (VTE) is a potentially preventable serious complication in patients with lung cancer undergoing thoracic operation. We examined the risk and timing of VTE after surgery for primary non-small cell lung cancer (NSCLC).

METHODS

All patients undergoing operation for NSCLC in Denmark between 2003 and 2021 were identified in the Danish Lung Cancer Registry. VTE events in the year after operation were assessed by stage, patient characteristics, and surgical procedure.

RESULTS

We identified 13,197 patients who underwent operation for NSCLC in 2003 to 2021 (mean age, 67.6 years; 50% female); 10,524 (79.7%) had stage I-II NSCLC, and 2673 (20.3%) had stage III-IV. During 1-year follow-up, there were 335 VTE events, yielding a rate of 2.87 events/100 person-years and an absolute risk of 3.3% (95% CI, 2.3-4.0). VTE risk increased with advancing cancer stage (1.8% for stage I vs 3.9% for stage IV) but varied little by pathologic type, sex, and comorbidity level. Bilobectomy was associated with highest VTE risk (4.8%; 95% CI, 3.2-6.9), followed by pneumonectomy (3.5%; 95% CI, 2.3-5.0). The hazard of VTE was highest during the first 3 months after operation, after which it declined. For stage IV cancer, hazards increased again after 6 months. At 1 year, all-cause death was 12.6% (95% CI, 12.0%-13.1%).

CONCLUSIONS

VTE developed in 3.3% of patients undergoing operation for NSCLC, most commonly within 3 months postoperatively. Prolonged thromboprophylaxis could be considered, particularly in those with advanced cancer stage and undergoing extended resections.

Care pathways for patients with cancer-associated thrombosis: From diagnosis to long-term follow-up

Venous thromboembolism (VTE) in patients with cancer is associated with a high risk of bleeding complications and hospitalisation, as well as with increased mortality. Good practice recommendations for diagnosis and treatment of VTE in patients with cancer have been developed by a number of professional bodies. Although these guidelines provide consistent recommendations on what treatment should be offered to patients presenting with cancer-associated thromboembolism (CAT), many questions remain unanswered, in particular about the modalities of management (Who? When? Where?) and, for this reason, we have developed a consensus proposal for an appropriate multidisciplinary care pathway for patients with CAT, which is presented in this article. The proposal was informed by the recent scientific literature retrieved through a systematic literature review. This proposal is centred on the development of a shared care plan individualised to each patient's needs and expectations, patient information and shared decision-making to promote adherence, involvement of all relevant hospital- and community- based healthcare providers in the development and implementation of the care plan, and regular re-evaluation of the treatment strategy.

A consensus viewpoint on the role of direct factor Xa inhibitors in the management of cancer-associated venous thromboembolism in the UK

OBJECTIVE

Cancer patients are at high risk of venous thromboembolism (VTE), a significant cause of cancer-related death. Historically, low molecular weight heparins (LMWH) were the gold standard therapy for cancer-associated VTE, but recent evidence supports the use of direct factor Xa inhibitors in cancer-associated VTE and this is now reflected in many guidelines. However, uptake of direct factor Xa inhibitors varies and guidance on the use of direct factor Xa inhibitors in specific cancer sub-populations and clinical situations is lacking. This review presents consensus expert opinion alongside evaluation of evidence to support healthcare professionals in the use of direct factor Xa inhibitors in cancer-associated VTE.

METHODS

Recent guidelines, meta-analyses, reviews and clinical studies on anticoagulation therapy for cancer-associated VTE were used to direct clinically relevant topics and evidence to be systematically discussed using nominal group technique. The consensus manuscript and recommendations were developed based on these discussions.

RESULTS

Considerations when prescribing anticoagulant therapy for cancer-associated VTE include cancer site and stage, systemic anti-cancer therapy (including vascular access), drug-drug interactions, length of anticoagulation, quality of life and needs during palliative care. Treatment of patients with kidney or liver impairment, gastrointestinal disorders, extremes of bodyweight, elevated bleeding or recurrence risk, VTE recurrence and COVID-19 is discussed.

CONCLUSION

Anticoagulant therapy for cancer-associated VTE patients should be carefully selected with consideration given to the relative benefits of specific drugs when individualizing care. Direct factor Xa inhibitors are typically the treatment of choice for preventing VTE recurrence in non-cancer patients and should also be considered as such for cancer-associated VTE in most situations.

Safe and effective treatment of venous Thromboembolism associated with Cancer: focus on direct Oral Anticoagulants in Asian patients

Cancer-associated thrombosis (CAT) poses a significant disease burden and the incidence in Asian populations is increasing. Anticoagulation is the cornerstone of treatment, but can be challenging due to the high bleeding risk in some cancers and the high risk of recurrent venous thromboembolism (VTE) in patients with malignancies. Direct oral anticoagulants (DOACs) are well established as first-choice treatments for VTE in non-cancer patients, offering a more convenient and less invasive treatment option than low-molecular-weight heparin (LMWH). Asian patients have exhibited comparable efficacy and safety outcomes with other races in trials of DOACs for VTE in the general population. Although no specific data are available in Asian patients with CAT, results from randomized controlled trials of apixaban, edoxaban, or rivaroxaban versus the LMWH, dalteparin, indicate that DOACs are a reasonable alternative to LMWH for anticoagulation in Asian patients with CAT. This is further supported by analyses of real-world data in Asian populations demonstrating the efficacy and safety of DOACs in Asian patients with CAT. Apixaban, edoxaban, or rivaroxaban are recommended in the most recently updated international guidelines as first-line therapy for CAT in patients without gastrointestinal or genitourinary cancers and at low risk of bleeding. An increased risk of major gastrointestinal bleeding was evident with edoxaban or rivaroxaban, but not apixaban, versus dalteparin in the clinical trials, suggesting that apixaban could be a safe alternative to LMWH in patients with gastrointestinal malignancies. Determining the optimal anticoagulant therapy for patients with CAT requires careful consideration of bleeding risk, tumor type, renal function, drug-drug interactions, financial costs, and patients' needs and preferences.

Endovascular Management of Venous Thromboembolic Disease in the Oncologic Patient Population

PURPOSE OF REVIEW

Venous thromboembolic disease causes significant mortality and morbidity in the oncologic patient population. Recently, minimally invasive endovascular technologies have been developed as an adjunct to antithrombotic therapy for the management of DVT and PE. The current and potential roles for endovascular treatment of cancer-associated venous thromboembolism (VTE) will be reviewed in this article.

RECENT FINDINGS

The recent NCCN guidelines recommend endovascular therapy in patients eligible for therapeutic anticoagulation who present with life-, organ-, or limb-threatening thrombosis. However, symptomatic non-life-threatening VTE can negatively affect QOL and physical function, both of which have prognostic implications in the cancer population. Endovascular therapies have been shown to improve physical function and QOL in prospective trials performed in a non-oncologic patient population as well as small retrospective studies in the cancer population. In addition to treating life- and limb-threatening thrombosis, endovascular therapy for VTE can improve QOL and physical function in comparison to anticoagulation alone. Prospective trials are warranted to assess the benefit of endovascular therapy for quality of life-years, performance status, and overall survival in the oncologic patient population.

Direct Oral Anticoagulants for the Treatment of Cancer-Associated Venous Thromboembolism: A Latin American Perspective

Venous thromboembolism (VTE) is a leading cause of morbidity and mortality in patients with cancer. On the basis of results from randomized controlled trials, direct oral anticoagulants (DOACs) are now recommended for the treatment of cancer-associated VTE. The decision to use a DOAC requires consideration of bleeding risk, particularly in patients with gastrointestinal (GI) malignancies, the cost-benefit and convenience of oral therapy, and patient preference. While efficacy with apixaban, edoxaban, and rivaroxaban versus dalteparin has been consistent in the treatment of cancer-associated VTE, heterogeneity is evident with respect to major GI bleeding, with an increased risk with edoxaban and rivaroxaban but not apixaban. Although cost and accessibility vary in different countries of Latin America, DOACs should be considered for the long-term treatment of cancer-associated VTE in all patients who are likely to benefit. Apixaban may be the preferred DOAC in patients with GI malignancies and LMWH may be preferred for patients with upper or unresected lower GI tumors. Vitamin K antagonists should only be used for anticoagulation when DOACs and low molecular weight heparin are inaccessible or unsuitable.

Cancer-Associated ThrOmboSIs - Patient-Reported OutcoMes With RivarOxaban (COSIMO) - Baseline characteristics and clinical outcomes

BACKGROUND

Patients with cancer-associated thrombosis (CAT) have a high risk of recurrent venous thromboembolic events, which contribute to significant morbidity and mortality. Direct oral anticoagulants may provide a convenient treatment option for these patients.

OBJECTIVES

To assess clinical characteristics and outcomes of patients with active cancer changing to rivaroxaban after ≥4 weeks of standard therapy for the treatment of venous thromboembolism (VTE) in clinical practice. This analysis focused on secondary outcomes of Cancer-associated thrOmboSIs - Patient-reported outcoMes with rivarOxaban (COSIMO).

PATIENTS

COSIMO was a multinational, prospective, noninterventional, single-arm cohort study. Overall, 505 patients received at least one dose of rivaroxaban; 96.6% changing from low-molecular-weight heparin, 1.6% from a vitamin K antagonist, and 1.8% from fondaparinux.

RESULTS

Most patients had solid tumors (n = 449; 88.9%) and approximately half of these patients had metastases. The qualifying venous thromboembolic event was deep vein thrombosis (DVT) in 45.3% of patients, pulmonary embolism (PE) in 37.2% of patients, DVT with PE in 9.7% of patients, and catheter-associated DVT in 7.5% of patients. Approximately 75.1% of patients received rivaroxaban for at least 3 months; 150 (29.7%) patients received concomitant chemotherapy during the study. VTE recurrence, major bleeding, nonmajor bleeding, and major adverse cardiovascular events occurred in 18 (3.6%), 18 (3.6%), 81 (16.0%), and 12 (2.4%) patients, respectively.

CONCLUSIONS

In patients with CAT who changed to rivaroxaban treatment after ≥4 weeks of standard therapy, the observed incidence proportions of recurrent VTE and bleeding events were in keeping with the recognized effectiveness and safety profile of rivaroxaban for the treatment of CAT.

Anticoagulants for the treatment of venous thromboembolism in patients with cancer: A comprehensive systematic review, pairwise and network meta-analysis

Cancer-associated venous thromboembolism (VTE) is associated with high VTE recurrence and bleeding. We included all randomized clinical trials that evaluated the efficacy and safety of various anticoagulants in cancer-associated VTE. Trial-level data were extracted from 13 trials. Aggregate odds ratios (ORs) were calculated using direct and network meta-analysis. The primary outcome was VTE (pulmonary embolism and/or deep vein thrombosis) recurrence. Secondary outcomes were major bleeding and all-cause mortality. We identified 13 trials with 4869 patient-years of follow-up (6595 total patients; mean age 62.4 ± 12.2; 50.4 % female; 17.7 % hematological malignancies). The most common cancer type was colorectal and 48 % had metastatic cancer at baseline. Compared to vitamin-K-antagonists (VKAs), non-vitamin-K-antagonist-oral-anticoagulants (NOACs) were associated with significantly reduced VTE recurrence (OR, 0.58; 95 % CI, 0.40-0.83) and reduced major bleeding risks (OR, 0.56; 95 % CI, 0.35-0.91). However, no differences were observed in the subgroup analysis of patients with active cancer. Although NOACs were associated with reduced VTE recurrence compared with low-molecular-weight-heparin (LMWHs) (OR, 0.46; 95 % CI, 0.25- 0.85), there was a significant increased major bleeding in high-quality trials. LMWHs were associated with significantly reduced VTE recurrence compared with VKAs (OR, 0.52; 95 % CI, 0.39-0.71) and similar bleeding risks. Conclusions: Among patients with cancer-associated VTE, NOACs were associated with significantly reduced VTE recurrence and bleeding compared with VKAs, however, with similar outcomes in the active cancer population. NOACs were associated with reduced VTE recurrence but higher bleeding risks compared with LMWHs. LMWHs were associated with significantly reduced VTE recurrence and similar bleeding compared with VKAs.

Efficacy and safety of direct oral anticoagulants versus low-molecular-weight heparin in patients with cancer: a systematic review and meta-analysis

The efficacy and safety of direct oral anticoagulants (DOACs) versus low-molecular-weight heparin (LMWH) are still debated in the treatment of patients with cancer, and the optimal duration of therapy remains uncertain. Electronic databases (PubMed, Embase, and Cochrane Library) were searched to retrieve studies on the efficacy and safety of DOACs versus LMWH in treating patients with cancer from January 1980 to October 2018. The primary efficacy and safety endpoints were recurrent venous thromboembolism (VTE) and major bleeding. Our study included two randomized controlled trials (RCTs) and nine observational studies, together comprising 4509 patients with cancer. The pooled estimates indicated that DOACs led to a modest reduction recurrent VTE in the RCTs [RR: 0.63, 95% confidence interval (CI), 0.42-0.96, P = 0.03] and in the observational studies (RR: 0.74, 95% CI, 0.58-0.93, P = 0.011), without increasing the risk of major bleeding for observational studies (P = 0.805), but increased for RCTs (P = 0.017). The same trends were observed in the rivaroxaban subgroup. Moreover, subgroup analyses according to the treatment duration indicated that DOACs significantly reduced the incidence of recurrent VTE (P = 0.006 at 6 months; P < 0.001 at 12 months) without significant differences in major bleeding compared with LMWH at 6 or 12 months. Patients with cancer who received DOACs exhibited a significant reduction in recurrent VTE with no increased risk of major bleeding compared with LMWH. DOACs may be an alternative choice for long-term anticoagulant therapy in patients with cancer.

Prevention of venous thromboembolism in patients with cancer with direct oral anticoagulants: A systematic review and meta-analysis

BACKGROUND

Patients with cancer are of a high level risk of venous thromboembolism (VTE). Low molecular weight heparin (LMWH) is recommended as the normal treatment for cancer-associated venous thrombosis. Recently, some studies suggest that patients with cancer-associated venous thrombosis can get a good efficacy and safety profile from treating with direct oral anticoagulants (DOACs) compared with other anticoagulants. However, when it comes to the efficacy of DAOCs in preventing VTE in patient with cancer, the data are limited. Thus, we performed such a meta-analysis to determine the efficacy and safety of DOACs in preventing VTE in patient with cancer compared with LMWHs.

METHODS

Medline/PubMed and CENTRAL (The Cochrane Central Register of Controlled Trials) were systematically searched for relevant studies. For each trial, data on VTE, major bleeding, or bleeding were extracted by 2 reviewers independently. Pooled risk ratios (RRs) were calculated by using Review Manager 5.3 software and the significance was determined by the Z test.

RESULTS

A total of 6 studies with 7185 patients were included in our meta-analysis. DOACs (RR = 0.55, 95% confidence interval [95%CI]: 0.34-0.90, I = 31%) had a similar prevention effect of VTE to LMWH (RR = 0.59, 95% CI: 0.37-0.95, I = 59%). DOACs (RR = 1.52, 95% CI: 0.99-2.33, I = 0%) yielded a similar bleeding occurrence rate compared with LMWH (RR = 1.35, 95% CI: 1.07-1.70, I = 35%). DOACs (RR = 1.95, 95% CI: 0.88-4.30, I = 0%) showed a sight higher major bleeding occurrence rate than LMWH (RR = 1.38, 95% CI: 0.88-2.14, I = 0%).

CONCLUSION

DOACs show comparable efficacy to LMWH in cancer patients without VTE with a slightly higher major bleeding occurrence rate. DOACs are inclined to be an alternative thromboprophylaxis strategy in cancer patients as they have superiorities compared to traditional anticoagulation agents. Further studies are still demanded as exiting relevant researches are limited.

Non-vitamin K Antagonist Oral Anticoagulants (NOAC) as an Alternative Treatment Option in Tumor-Related Venous Thromboembolism

BACKGROUND

The risk of venous thromboembolism (VTE) is 4 to 7 times higher in cancer patients than in the normal population. Moreover, cancer patients who take anticoagulants suffer more frequently from hemorrhagic complications and VTE recurrences. Patients often find low-molecular-weight heparin (LMWH) treatment unpleasant; approximately 20% stop taking LMWH during the first six months of treatment.

METHODS

Based on a non-systematic literature search, an interdisciplinary group of specialists (hematology, oncology, hemostaseology, and angiology) developed a set of recommendations concerning the treatment of tumor-related thrombosis with non-vitamin K antagonist oral anticoagulants (NOAC).

RESULTS

Patient-, tumor-, and tumor-treatment-related factors and clinical situations were identified that should be considered in therapeutic decision-making in the indi- vidual case. NOAC may be an alternative that lessens the rate of VTE recurrence (though at the cost of more hemorrhagic complications), without lessening mortality. Moreover, many factors need to be considered that can limit the utility of NOAC treatment or even make it impossible.

CONCLUSION

It seems likely that, in future, the treatment of tumor-related VTE will often not involve a single decision to use either NOAC or LWMH, but rather a switching of treatment in either of two directions: from LWMH to NOAC in stable phases of the underlying malignant disease, conferring better quality of life to suitable patients; or from NOAC to LWMH, e.g., in patients suffering from emesis or thrombocytopenia, to whom the greater clinical experience with LWMH, parenteral application, or stepwise dose titration can confer benefits.

Anticoagulant Activity of Sulfated Ulvan Isolated from the Green Macroalga Ulva rigida

(1) Background: Brown and red algal sulfated polysaccharides have been widely described as anticoagulant agents. However, data on green algae, especially on the Ulva genus, are limited. This study aimed at isolating ulvan from the green macroalga Ulva rigida using an acid- and solvent-free procedure, and investigating the effect of sulfate content on the anticoagulant activity of this polysaccharide. (2) Methods: The obtained ulvan fraction was chemically sulfated, leading to a doubling of the polysaccharide sulfate content in a second ulvan fraction. The potential anticoagulant activity of both ulvan fractions was then assessed using different assays, targeting the intrinsic and/or common (activated partial thromboplastin time), extrinsic (prothrombin time), and common (thrombin time) pathways, and the specific antithrombin-dependent pathway (anti-Xa and anti-IIa), of the coagulation cascade. Furthermore, their anticoagulant properties were compared to those of commercial anticoagulants: heparin and Lovenox®. (3) Results: The anticoagulant activity of the chemically-sulfated ulvan fraction was stronger than that of Lovenox® against both the intrinsic and extrinsic coagulation pathways. (4) Conclusion: The chemically-sulfated ulvan fraction could be a very interesting alternative to heparins, with different targets and a high anticoagulant activity.

Risk of recurrence and bleeding in patients with cancer-associated venous thromboembolism treated with rivaroxaban: A nationwide cohort study

BACKGROUND

Rivaroxaban could be an attractive alternative to low molecular weight heparin for the treatment of cancer-associated venous thromboembolism (VTE) but the safety and effectiveness remain unclear. We examined risk of recurrent VTE and major bleeding associated with rivaroxaban treatment of cancer-associated VTE.

METHODS

Through linkage of nationwide Danish registries, we identified all adults with cancer-associated VTE initiating treatment with rivaroxaban, 2012-2017. We estimated rates and absolute risk of the primary outcome of recurrent VTE and major bleeding; all-cause mortality was studied as a secondary outcome.

RESULTS

We identified 8901 patients with cancer-associated VTE of whom 476 (5.3%) redeemed a prescription for rivaroxaban within 30 days of VTE diagnosis (mean age 71.5 years, 41% females, 57% with pulmonary embolism). Median time from cancer diagnosis to rivaroxaban prescription was 31 days (interquartile range 12-73 days). Most frequent cancers were gastrointestinal (26.1%), genitourinary (23.3%), and hematological cancer (12.6%). Few had distant metastases (7.1%). At 6 months, recurrent VTE occurred in 6.1% (15.1 events per 100 person-years) with the highest absolute risks for genitourinary cancer (8.1%), gastrointestinal cancer (7.3%), and breast cancer (6.5%). Major bleeding occurred in 1.9% (5.3 events per 100 person-years), in particular, in genitourinary cancer (4.5%) and lung cancer (4.2%). Eighty deaths (17.8%) occurred during follow up.

CONCLUSION

In this clinical practice setting, rivaroxaban was rarely used for cancer-associated VTE. However, among those who received rivaroxaban, the treatment appeared safe and effective with rates comparable to previous studies of selected populations.

Anticoagulation in Cancer Patients: a Summary of Pitfalls to Avoid

PURPOSE OF REVIEW

Venous thromboembolism (VTE) is a leading cause of morbidity and mortality in cancer patients, and its management is often associated with complications including risk of recurrent VTE and bleeding. Here, we review the current data on pitfalls during anticoagulation in cancer patients and measures necessary to avoid them.

RECENT FINDINGS

Although low-molecular-weight heparin monotherapy has been the standard of treatment for several years, emerging data for direct oral anticoagulants (DOACs) are leading to new paradigms in treatment. Reports of recent randomized trials suggest a lower risk of recurrent thrombosis but higher risk of bleeding, particularly in gastrointestinal cancer patients, with DOACs. Careful patient selection and individualization of therapy based on risk of bleeding as well as recurrent VTE are keys. Problems like bleeding, recurrence, thrombocytopenia, drug-drug interactions, renal impairment, nausea-vomiting along with concerns about adherence arise during anticoagulation in cancer patients. However, with adequate pre-treatment assessment, correct anticoagulant selection and proper monitoring during anticoagulation, these issues can be addressed safely and effectively.

Position paper of the Italian Society of Internal Medicine (SIMI) on prophylaxis and treatment of venous thromboembolism in patients with cancer

Cancer patients are at high risk of developing thrombotic events, including venous thromboembolism (VTE) [deep venous thrombosis (DVT) and pulmonary embolism (PE)], and arterial thrombosis. DVT and PE represent the second leading cause of death in cancer patients; moreover, the development of thromboembolic events in cancer patients is linked to a greater need of hospitalization and frequency of side effects during treatment, in particular bleeding, and to an increased risk of recurrence during and following antithrombotic therapy. The thromboembolic risk may be different in different subgroups of cancer population, being highest in patients with metastatic disease, patients with pancreas, stomach, kidney or primary brain cancer, or during therapeutic interventions or surgery. This document focuses on several relevant topics including the epidemiology and pathogenesis of cancer-associated VTE, the current and future strategies of primary prevention and anticoagulant treatment, and the management of bleeding complications. The main literature data are discussed in detail, including, when available, evidence from randomized clinical trials and meta-analyses, international guidelines statements, the results of recently published trials comparing direct oral anticoagulants to low molecular weight heparin, and the design and aims of ongoing trials on prevention/treatment of cancer-associated VTE.

Etiology and Management of Upper-Extremity Catheter-Related Thrombosis in Cancer Patients

Central venous access devices are a critical instrument in the treatment and supportive care delivery for oncology patients. Catheter-related thrombosis (CRT) is a common complication of central venous access devices in oncology patients. Risk factors for CRT include patient-, device-, and treatment-related risk factors. Treatment of CRT is indicated to reduce symptoms, prevent catheter malfunction, prevent recurrent DVT or thromboembolic pulmonary embolism, and minimize the risk of post-thrombotic syndrome. Minimal prospective data exist on the prevention and treatment of catheter-related thromboses in cancer patients. As such recommendations largely are derived from data in the lower-extremity DVT and PE studies in cancer and non-cancer patients. Based on the available literature, primary pharmacologic prophylaxis against CRT is not recommended in cancer patients. Treatment options for CRT include catheter removal, anticoagulation, catheter-directed thrombolysis, or surgical thrombectomy. Current evidence-based guidelines recommend LMWH as the anticoagulant of choice. However, recent data showing efficacy and safety of DOACs in cancer-related VTE may be extrapolated to treatment of CRT in cancer patients. In patients with CRT, catheter removal should be pursued if continued vascular access is no longer needed, the catheter is dysfunctional, a catheter-associated infection is present, or if CRT symptoms do not resolve with anticoagulation alone. Catheter-directed thrombolysis is reserved for rare severe cases of CRT. Herein we discuss the pathophysiology, clinical presentation, diagnosis, and general management of CRT in cancer patients.

Management of venous thromboembolism in patients with cancer

Current guidelines for anticoagulant therapy do not so far suggest any form of differentiated approach to cancer patients with venous thromboembolism (VTE). This review article provides an overview of the published literature in cancer patients with VTE, mostly using data from the RIETE registry. Our findings provide some insights into what factors may be used to guide physicians in adapting recommended anticoagulant regimens to the individual patient, as oncologists are increasingly doing with cancer treatments. For instance, patients presenting with deep vein thrombosis (DVT) alone might benefit from curtailing treatment intensity as anticoagulant therapy progresses. The site of cancer also needs to be considered. In patients with incidental PE or splanchnic vein thrombosis, we should be more cautious before prescribing anticoagulant therapy. The optimal duration of anticoagulant therapy is unknown.

Use of Direct Oral Anticoagulants in Patients with Cancer: Practical Considerations for the Management of Patients with Nausea or Vomiting

Direct oral anticoagulants (DOACs) have proven efficacy and safety and are approved for use in the prevention and treatment of thromboembolic events in patients with venous thromboembolism (VTE) and those with atrial fibrillation (AF). There is no clear guidance on the use of DOACs in the significant proportion of these patients who have or will develop concomitant cancer. The occurrence of nausea and vomiting in these patients, despite implementation of guideline-recommended antiemetic strategies, is a particular concern because it may affect oral drug intake and consequently outcomes with anticoagulation therapy.Here, we review recent data on the incidence and management of cancer-associated nausea and vomiting and the current evidence and guidance relating to the use of DOACs in patients with cancer. On the basis of this evidence, an international working group of experts in the fields of cancer-associated thrombosis/hemostasis, hematology, and oncology discussed key issues related to the use of DOACs in patients with VTE or AF and cancer who are at risk of nausea and vomiting and developed some consensus recommendations. We present these consensus recommendations, which outline strategies for the use and management of anticoagulants, including DOACs, in patients with VTE or AF and cancer for whom oral drug intake may pose challenges. Guidance is provided on managing patients with gastrointestinal obstruction or nausea and vomiting that is caused by cancer treatments or other cancer-related factors.The recommendations outlined in this review provide a useful reference for health care professionals and will help to improve the management of anticoagulation in patients with VTE or AF and cancer.

IMPLICATIONS FOR PRACTICE

Direct oral anticoagulants (DOACs) offer several advantages over traditional anticoagulants, including ease of administration and the lack of need for routine monitoring. However, the management of patients with an indication for anticoagulation and concomitant cancer, who are at high risk of thromboembolic events, presents several challenges for administering oral therapies, particularly with regard to the risk of nausea and vomiting. In the absence of robust data from randomized trials and specific guidelines, consensus recommendations were developed for healthcare professionals regarding the use of DOACs in patients with cancer, with a focus on the management of patients who are at risk of nausea and vomiting.

Vitamin K Antagonists After 6 Months of Low-Molecular-Weight Heparin in Cancer Patients with Venous Thromboembolism

BACKGROUND

Low-molecular-weight heparin (LMWH) is the treatment of choice in cancer patients with venous thromboembolism. However, data on continuing LMWH treatment beyond 6 months remain scanty.

METHODS

We used the RIETE (Registro Informatizado Enfermedad TromboEmbólica) registry to compare the rate of venous thromboembolism recurrences and major bleeding appearing beyond the first 6 months of anticoagulant therapy in cancer patients with venous thromboembolism, according to therapy with LMWH or vitamin K antagonists (VKA). We performed a propensity score-matched cohort study.

RESULTS

After propensity matching, 482 cancer patients continued to receive LMWH and 482 switched to VKA. During the course of anticoagulant therapy (mean 275.5 days), 57 patients developed venous thrombosis recurrences (recurrent pulmonary embolism 26, recurrent deep vein thrombosis 29, both 2), 28 had major bleeding, 38 had nonmajor bleeding, and 129 died. No patient died of recurrent venous thrombosis, and 5 patients died of bleeding (2 were on LMWH, 3 on VKA). Patients who continued with LMWH had a similar rate of deep vein thrombosis recurrences (relative risk [RR] 1.41; 95% confidence interval [CI], 0.68-2.93), pulmonary embolism recurrences (RR 0.73; 95% CI, 0.34-1.58), major bleeding (RR 0.96; 95% CI, 0.51-1.79), or nonmajor bleeding (RR 1.15; 95% CI, 0.55-2.40), compared with those who switched to VKA, but a higher mortality rate (RR 1.58; 95% CI, 1.13-2.20).

CONCLUSIONS

In cancer patients with venous thromboembolism who completed 6 months of LMWH therapy, switching to VKA was associated with a similar risk of venous thrombosis recurrences or bleeding when compared with patients who continued LMWH.

[Cancer and venous thromboembolism recurrence: The keys for an optimal management]

Low-molecular-weight heparins (LMWH) are to date the standard for 3-to-6-month treatment of cancer-associated thrombosis (CAT) as they are consistently recommended by international clinical practice guidelines. Despite the high risk of VTE recurrence and death in patients with cancer and the favorable benefit-risk profile of LMWH demonstrated in randomized-control studies, the implementation of treatment guidelines remains insufficient in the clinical practice. A systematic review of observational studies, registries and surveys reveals that approximately only 50% of patients with CAT are treated according to practice guidelines while both physicians and patients may be accountable for this situation. Based on the few available published data, we have observed differences between guidelines and clinical practice and we have identified factors influencing patient's management with the perspective to improve adherence to clinical practice guidelines in patients with CAT. Improving the implementation of clinical practice guidelines requires a better knowledge of physician and patient-related factors that influence therapeutic decisions. A global approach of patients with CAT is warranted to optimize the therapeutic management of cancer-associated VTE.

Higher Adherence to Treatment With Low-Molecular-Weight-Heparin Nadroparin Than Enoxaparin Because of Side Effects in Cancer-Associated Venous Thromboembolism

Current guidelines recommend low-molecular-weight-heparins (LMWH) monotherapy for 3 to 6 months as first-line treatment for cancer-associated venous thromboembolism (VTE). In clinical practice, enoxaparin and nadroparin are common agents used. However, differences in therapy adherence between these LMWHs have never been reported. Therefore, our aim was to compare adherence to enoxaparin and nadroparin in patients with cancer-associated VTE. Consecutive patients with active cancer and objectively confirmed VTE, treated at a Dutch or a Spanish hospital, were followed during LMWH therapy with a maximum of 180 days. Cumulative incidences of discontinuation of both LMWHs were estimated and compared according to the Kaplan-Meier method, applying a competing risk analysis to correct for mortality. A total of 366 patients were analyzed during LMWH treatment, of whom 284 patients (78%) were treated with enoxaparin and 82 (22%) with nadroparin. The cumulative incidence of discontinuation of enoxaparin and nadroparin treatment because of side effects was 30% (95% confidence interval [CI] 24–36) and 8.8% (95% CI 1.1–15), respectively. Competing risk analysis revealed a higher number of patients discontinuing enoxaparin due to side effects (adjusted hazard ratio [HR]: 2.8; 95% CI 1.06–7.2). Pain at the injection site was the most common reason of discontinuation in patients using enoxaparin, occurring in 32 patients, while it occurred in 1 patient using nadroparin (adjusted HR: 4.0; 95% CI 0.52–31). This analysis reveals that enoxaparin was associated with a higher risk of discontinuation because of side effects compared to nadroparin. However, given the nature of the patient groups, these findings should be followed by future studies.

When can we stop anticoagulation in patients with cancer-associated thrombosis?

The optimal duration of anticoagulant therapy in patients with cancer-associated venous thromboembolism (VTE) is unknown. Without well-designed studies evaluating the efficacy, safety, and cost-effectiveness of continuing anticoagulant therapy beyond the acute treatment period of 3 to 6 months, evidence-based recommendations are lacking. Consensus guidelines generally suggest continuing anticoagulation treatment in patients with active cancer or receiving cancer treatment, with periodic reassessment of the risks and benefits. Unfortunately, with very little published data on the epidemiology of cancer-associated VTE beyond the initial 6 months, it is not possible for clinicians and patients to weigh risks and benefits in a quantitatively informed manner. Further research is needed to provide reliable and contemporary estimates on the risk of recurrent VTE off anticoagulant therapy, risk of bleeding on anticoagulant therapy, case fatality or all-cause mortality, and other important consequences of living with cancer-associated VTE. This chapter provides an overview of the published literature on real-world data on anticoagulant therapy use, the risks and risk factors of recurrent VTE and bleeding, and patient preference and values regarding long-term anticoagulation treatment. It will conclude with a pragmatic, experience-informed approach for tailoring anticoagulant therapy in patients with cancer-associated VTE.

When can we stop anticoagulation in patients with cancer-associated thrombosis?

The optimal duration of anticoagulation in patients with cancer-associated venous thromboembolism (VTE) is unknown. Without well-designed studies evaluating the efficacy, safety and cost-effectiveness of continuing anticoagulant therapy beyond the acute treatment period of 3 to 6 months, evidence-based recommendations are lacking. Consensus guidelines generally suggest continuing anticoagulation in patients with active cancer or receiving cancer treatment, with periodic reassessment of the risks and benefits. Unfortunately, with very little published data on the epidemiology of cancer-associated VTE beyond the initial 6 months, it is not possible for clinicians and patients to weigh risks and benefits in a quantitatively informed manner. Further research is needed to provide reliable and contemporary estimates on the risk of recurrent VTE off anticoagulation, risk of bleeding on anticoagulation, case fatality or all-cause mortality, and other important consequences of living with cancer-associated VTE. This chapter provides an overview of the published literature on real-world data on anticoagulant therapy use, the risks and risk factors of recurrent VTE and bleeding, and patient preference and values regarding long-term anticoagulation. It will conclude with a pragmatic, experience-informed approach for tailoring anticoagulant therapy in patients with cancer-associated VTE.

Management of incidental pulmonary embolism

Incidental pulmonary embolism (PE) is a frequent finding on routine computed tomography (CT) scans of the chest, occurring in 1.1% of coronary CT scans and 3.6% of oncological CT scans. Despite this high frequency, optimal management of incidental PE has not been addressed in clinical trials and remains the subject of debate. Although these CT scans have not been performed with a dedicated PE protocol and have suboptimal contrast enhancement, diagnosis of incidental PE has been shown to be accurate up to the segmental and subsegmental arteries. The embolic load in incidental PE is lower than that in symptomatic PE. Even so, observational studies suggest that the natural course of incidental PE is similar to that of symptomatic PE with regard to the risk of recurrent venous thrombotic disease and mortality. Interestingly, the increased use of more advanced CT technology has coincided with an increase in the rate of incidental subsegmental PE, as is the case for symptomatic subsegmental PE. Although clinical trials are lacking, and observational data are limited to cancer-associated incidental PE, the consensus is that the management of incidental PE is identical to that of symptomatic PE, including the choice of optimal drug class, outpatient treatment and total duration of treatment.