A Phase II Study to Compare the Safety and Efficacy of Direct Oral Anticoagulants versus Subcutaneous Dalteparin for Cancer-Associated Venous Thromboembolism in Patients with Advanced Upper Gastrointestinal, Hepatobiliary and Pancreatic Cancer: PRIORITY

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

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

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.

Non-Vitamin K Antagonist Oral Anticoagulants versus Low Molecular Weight Heparin for Cancer-Related Venous Thromboembolic Events: Individual Patient Data Meta-Analysis

Venous thromboembolism (VTE) is a leading cause of morbidity and mortality in cancer patients. Low molecular weight heparin (LMWH) has been the standard of care but new guidelines have approved the use of non-vitamin K antagonist oral anticoagulants (NOAC). By conducting an individual patient data (IPD) meta-analysis of randomised controlled trials (RCTs) comparing the outcomes of NOAC versus LMWH in cancer patients, we aim to determine an ideal strategy for the prophylaxis of VTE and prevention of VTE recurrence. Three databases were searched from inception until 19 October 2022. IPD was reconstructed from Kaplan-Meier curves. Shared frailty, stratified Cox and Royston-Parmar models were fit to compare the outcomes of venous thromboembolism recurrence and major bleeding. For studies without Kaplan-Meier curves, aggregate data meta-analysis was conducted using random-effects models. Eleven RCTs involving 4844 patients were included. Aggregate data meta-analysis showed that administering NOACs led to a significantly lower risk of recurrent VTE (RR = 0.65; 95%CI: 0.50-0.84) and deep vein thrombosis (DVT) (RR = 0.60; 95%CI: 0.40-0.90). In the IPD meta-analysis, NOAC when compared with LMWH has an HR of 0.65 (95%CI: 0.49-0.86) for VTE recurrence. Stratified Cox and Royston-Parmar models demonstrated similar results. In reducing risks of recurrent VTE and DVT among cancer patients, NOACs are superior to LMWHs without increased major bleeding.

Safety and Effectiveness of Direct Oral Anticoagulants for the Treatment of Gastrointestinal Cancer-Associated Venous Thromboembolism

BACKGROUND

Patients with gastrointestinal cancer (GICA) are at high risk for venous thromboembolism (VTE). Data from randomized clinical trials in cancer-associated VTE suggest that direct oral anticoagulants (DOACs) conferred similar or superior efficacy but a heterogeneous safety profile in patients with GICA. We compared the safety and effectiveness of DOACs in patients with GICA and VTE at MD Anderson Cancer Center.

MATERIALS AND METHODS

This was a retrospective chart review of patients with GICA and VTE receiving treatment with DOACs for a minimum of 6 months. Primary outcomes were the proportion of patients experiencing major bleeding (MB), clinically relevant non-major bleeding (CRNMB), and recurrent VTE. Secondary outcomes were time to bleeding and recurrent VTE.

RESULTS

A cohort of 433 patients with GICA who were prescribed apixaban (n = 300), or rivaroxaban (n = 133) were included. MB occurred in 3.7% (95% confidence interval [CI] 2.1-5.9), CRNMB in 5.3% (95% CI 3.4-7.9), and recurrent VTE in 7.4% (95% CI 5.1-10.3). The cumulative incidence rates of CRNMB and recurrent VTE were not significantly different when comparing apixaban to rivaroxaban.

CONCLUSION

Apixaban and rivaroxaban had a similar risk of recurrent VTE and bleeding and could be considered as anticoagulant options in selected patients with GICA and VTE.

Efficacy and Safety of Apixaban versus Dalteparin as a Treatment for Cancer-Associated Venous Thromboembolism: A Systematic Review and Meta-Analysis

Background and Objectives: Venous thromboembolism (VTE) is common in cancer patients. Anticoagulant therapy with low-molecular-weight heparins (LMWHs) and direct oral anticoagulants (DOACs), such as dalteparin and apixaban, have demonstrated efficacy and safety. However, more comparative research of these drugs is still needed. This study aimed to synthesize evidence on the efficacy of apixaban compared to dalteparin in reducing recurrent VTE, major bleeding, and clinically relevant non-major bleeding associated with cancer. Materials and Methods: We systematically searched the PubMed, Scopus, Web of Science, Embase, Cochrane Library, and ClinicalTrials databases up to 5 January 2023, for randomized controlled trials comparing apixaban versus dalteparin as treatment for cancer-associated VTE. Five studies were included. Effects according to meta-analyses were reported as relative risks (RRs) and their 95% confidence intervals (CIs). Results: It was found that 33 of 734 (4.5%) patients treated with apixaban and 56 of 767 (7.3%) with dalteparin had recurrent VTE as the efficacy outcome (RR 0.49, 95% CI 0.15-1.58, I2 38%). Major bleeding occurred in 25 of 734 patients treated with apixaban (3.4%) and 27 of 767 with dalteparin (3.5%) (RR 1.29, 95% CI 0.31-5.27, I2 59%). Likewise, clinically relevant non-major bleeding occurred in 64 of 734 patients treated with apixaban (8.7%) and 46 of 767 (5.9%) with dalteparin (RR 1.52, 95% CI 1.05-2.19, I2 0%). Conclusions: Apixaban showed a lower risk of recurrent VTE than dalteparin in patients with cancer-associated VTE, albeit with no statistical difference. Statistical significance was observed for no major clinically relevant bleeding but not for major bleeding.

Treatment of cancer-associated venous thromboembolism: A focus on special populations

Current evidence-based clinical practice guidelines recommend the use of both low-molecular-weight heparin (LMWH) and direct factor Xa inhibitors (apixapan, edoxaban and rivaroxaban) as first-line options for the treatment of venous thromboembolism (VTE) in patients with cancer. However, most of these guidelines refer to the general cancer patient population and provide limited guidance for specific subgroups of patients at particularly high risk of bleeding, such as those with gastrointestinal cancers, primary or metastatic brain tumors, thrombocytopenia, or renal impairment. In these complex populations, the management of cancer-associated thrombosis (CAT) poses unique challenges and requires a nuanced approach based on the primum non nocere principle. This comprehensive review critically examines the relevant literature and discusses the therapeutic options currently available for the management of CAT in these special situations.

Comparative Efficacy of Oral Apixaban and Subcutaneous Low Molecular Weight Heparins in the Treatment of Cancer-Associated Thromboembolism: A Meta-Analysis

Cancer patients' risk of developing venous thromboembolism (VTE) is four to seven times higher than the general population. Cancer-associated VTE (CA-VTE), is a leading cause of morbidity and mortality in cancer patients. Low Molecular Weight Heparin (LMWH) has historically been the mainstay treatment of CA-VTE; however, complications such as bleeding and recurrent VTE make it challenging to manage these patients. Recent randomized controlled trials (RCTs) have proven that direct oral anticoagulants (DOACs) are as efficacious as LMWHs in treating CA-VTE. We conducted a systematic review and meta-analysis to ascertain the efficacy and safety of LMWH and Apixaban for the treatment of CA-VTE. A systematic review was conducted using Medline, Embase, and Scopus, databases for all cohort studies, case-control studies, and RCTs in English comparing cancer patients undergoing treatment with Apixaban or LMWH to treat CA-VTE from inception-May 2023. The Review Manager program, version 5.4.1, was used for statistical analysis and the Mantel-Haenszel fixed-effects models to calculate the risk ratio (RR) and 95% confidence intervals (CIs) and the inverse variance approach to get the weighted mean difference for the continuous outcomes. Q-test for heterogeneity was used to examine statistical heterogeneity and an I2 statistics value >50% was defined as significant heterogeneity. A total of four studies were included, and the total number of patients was 1,632 across all studies. The Apixaban group was associated with a statistically significant increase in minor bleeding (RR 1.57; 95% CI (1.12, 2.21); p=0.009; I2=0%), but not for major and total bleeding. The Apixaban group showed a statistically significant lower risk of recurrent VTE when compared to the LMWH group (RR: 0.61; 95% CI (0.41, 0.92); p=0.02; I2 = 7%), and there was no statistically significant difference in terms of mortality between the two groups (RR: 0.89; 95% CI (0.73, 1.09); I2=0). Our findings suggest that Apixaban may be a favorable anticoagulant option for managing cancer-associated thromboembolism, as it demonstrated a lower risk of recurrent VTE. The risk of bleeding with DOAC in gastrointestinal cancers warrants further investigation.

Comparative Efficacy of Direct Oral Anticoagulants and Low-Molecular-Weight Heparin in Cancer-Associated Thromboembolism: A Systematic Review and Meta-Analysis

Patients diagnosed with cancer often experience an abnormal occurrence of venous thromboembolism (VTE) and its related complications. In order to evaluate the safety and effectiveness of both treatment approaches, we conducted a comprehensive systematic review and meta-analysis within the realm of cancer-associated thromboembolism. A thorough search was conducted across PubMed, the Cochrane Library, and Embase databases to find studies comparing direct oral anticoagulants (DOACs) with low molecular weight heparins (LMWHs) for the treatment of VTE in patients with malignancy. The analyses utilized the random-effects model. This meta-analysis included 11 studies. The results showed that DOACs were associated with a significantly reduced risk of VTE recurrence (RR: 0.67; 95% CI: 0.55, 0.81, p<0.0001; I2: 0%) and deep vein thrombosis (DVT) (RR: 0.63; 95% CI: 0.46, 0.86, p<0.0001; I2: 0%) compared to LMWHs. However, there was no significant difference in the risk of pulmonary embolism (PE) (RR: 0.76; 95% CI: 0.54, 1.06, p=0.11; I2: 11%) between the two groups. The use of DOACs was also associated with a non-significant increase in the risk of major bleeding events (RR: 1.23; 95% CI: 0.85, 1.78, p: 0.26; I2: 49%), while clinically relevant non-major bleeding (CRNMB) was significantly higher with DOACs (RR: 1.92; 95% CI: 1.11, 3.30, p: 0.02; I2: 81%). Secondary outcomes, such as survival rates and fatal PE, did not show significant differences between the two treatment groups. Our analysis indicates that direct oral anticoagulants exhibit a substantial decrease in the occurrence of VTE recurrence, deep vein thrombosis, and pulmonary embolism when compared to low molecular weight heparin in cancer-associated thromboembolism. However, it should be noted that DOACs carry a higher risk of CRNMB. Based on these findings, DOACs are recommended as a superior therapeutic option for managing cancer-associated thromboembolism compared to LMWH.

Oral direct thrombin inhibitors or oral factor Xa inhibitors versus conventional anticoagulants for the treatment of pulmonary embolism

BACKGROUND

Pulmonary embolism (PE) is a potentially life-threatening condition in which a clot can migrate from the deep veins, most commonly in the leg, to the lungs. Conventional treatment of PE used unfractionated heparin (UFH), low molecular weight heparin (LMWH), fondaparinux, and vitamin K antagonists (VKAs). Recently, two forms of direct oral anticoagulants (DOACs) have been developed: oral direct thrombin inhibitors (DTIs) and oral factor Xa inhibitors. DOACs have characteristics that may be favourable to conventional treatment, including oral administration, a predictable effect, no need for frequent monitoring or re-dosing, and few known drug interactions. This review reports the efficacy and safety of these drugs in the long-term treatment of PE (minimum duration of three months). This is an update of a Cochrane Review first published in 2015.  OBJECTIVES: To assess the efficacy and safety of oral DTIs and oral factor Xa inhibitors versus conventional anticoagulants for the long-term treatment of PE.

SEARCH METHODS

The Cochrane Vascular Information Specialist searched the Cochrane Vascular Specialised Register, CENTRAL, MEDLINE, Embase and CINAHL databases, the World Health Organization International Clinical Trials Registry Platform and the ClinicalTrials.gov trials registers to 2 March 2022. We checked the reference lists of relevant articles for additional studies.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) in which people with a PE confirmed by standard imaging techniques were allocated to receive an oral DTI or an oral factor Xa inhibitor compared with a conventional anticoagulant or compared with each other for the long-term treatment of PE (minimum duration three months).

DATA COLLECTION AND ANALYSIS

We used standard Cochrane methods. Our primary outcomes were recurrent PE, recurrent venous thromboembolism (VTE), and deep vein thrombosis (DVT). Secondary outcomes were all-cause mortality, major bleeding, and health-related quality of life. We used GRADE to assess the certainty of evidence for each outcome.

MAIN RESULTS

We identified five additional RCTs with 1484 participants for this update. Together with the previously included trials, we have included ten RCTs with a total of 13,073 participants. Two studies investigated an oral DTI (dabigatran) and eight studies investigated oral factor Xa inhibitors (three rivaroxaban, three apixaban, and two edoxaban). The studies were of good methodological quality overall.  Meta-analysis showed no clear difference in the efficacy and safety of oral DTI compared with conventional anticoagulation in preventing recurrent PE (odds ratio (OR) 1.02, 95% confidence interval (CI) 0.50 to 2.04; 2 studies, 1602 participants; moderate-certainty evidence), recurrent VTE (OR 0.93, 95% CI 0.52 to 1.66; 2 studies, 1602 participants; moderate-certainty evidence), DVT (OR 0.79, 95% CI 0.29 to 2.13; 2 studies, 1602 participants; moderate-certainty evidence), and major bleeding (OR 0.50, 95% CI 0.15 to 1.68; 2 studies, 1527 participants; moderate-certainty evidence). We downgraded the certainty of evidence by one level for imprecision due to the low number of events. There was also no clear difference between the oral factor Xa inhibitors and conventional anticoagulation in the prevention of recurrent PE (OR 0.92, 95% CI 0.66 to 1.29; 3 studies, 8186 participants; moderate-certainty evidence), recurrent VTE (OR 0.83, 95% CI 0.66 to 1.03; 8 studies, 11,416 participants; moderate-certainty evidence), DVT (OR 0.77, 95% CI 0.48 to 1.25; 2 studies, 8151 participants; moderate-certainty evidence), all-cause mortality (OR 1.16, 95% CI 0.79 to 1.70; 1 study, 4817 participants; moderate-certainty evidence) and major bleeding (OR 0.71, 95% CI 0.36 to 1.41; 8 studies, 11,447 participants; low-certainty evidence); the heterogeneity for major bleeding was significant (I2 = 79%). We downgraded the certainty of the evidence to moderate and low because of imprecision due to the low number of events and inconsistency due to clinical heterogeneity. None of the included studies measured health-related quality of life.

AUTHORS' CONCLUSIONS

Available evidence shows there is probably little or no difference between DOACs and conventional anticoagulation in the prevention of recurrent PE, recurrent VTE, DVT, all-cause mortality, and major bleeding. The certainty of evidence was moderate or low. Future large clinical trials are required to identify if individual drugs differ in effectiveness and bleeding risk, and to explore effect differences in subgroups, including people with cancer and obesity.

Oral direct thrombin inhibitors or oral factor Xa inhibitors versus conventional anticoagulants for the treatment of deep vein thrombosis

BACKGROUND

Deep vein thrombosis (DVT) is a condition in which a clot forms in the deep veins, most commonly of the leg. It occurs in approximately one in 1000 people. If left untreated, the clot can travel up to the lungs and cause a potentially life-threatening pulmonary embolism (PE). Previously, a DVT was treated with the anticoagulants heparin and vitamin K antagonists. However, two forms of direct oral anticoagulants (DOACs) have been developed: oral direct thrombin inhibitors (DTIs) and oral factor Xa inhibitors, which have characteristics that may be favourable compared to conventional treatment, including oral administration, a predictable effect, lack of frequent monitoring or dose adjustment and few known drug interactions. DOACs are now commonly being used for treating DVT: recent guidelines recommended DOACs over conventional anticoagulants for both DVT and PE treatment. This Cochrane Review was first published in 2015. It was the first systematic review to measure the effectiveness and safety of these drugs in the treatment of DVT. This is an update of the 2015 review.  OBJECTIVES: To assess the effectiveness and safety of oral DTIs and oral factor Xa inhibitors versus conventional anticoagulants for the long-term treatment of DVT.

SEARCH METHODS

The Cochrane Vascular Information Specialist searched the Cochrane Vascular Specialised Register, CENTRAL, MEDLINE, Embase and CINAHL databases and the World Health Organization International Clinical Trials Registry Platform and ClinicalTrials.gov trials registers to 1 March 2022.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) in which people with a DVT, confirmed by standard imaging techniques, were allocated to receive an oral DTI or an oral factor Xa inhibitor compared with conventional anticoagulation or compared with each other for the treatment of DVT.  DATA COLLECTION AND ANALYSIS: We used standard Cochrane methods. Our primary outcomes were recurrent venous thromboembolism (VTE), recurrent DVT and PE. Secondary outcomes included all-cause mortality, major bleeding, post-thrombotic syndrome (PTS) and quality of life (QoL). We used GRADE to assess the certainty of evidence for each outcome.

MAIN RESULTS

We identified 10 new studies with 2950 participants for this update. In total, we included 21 RCTs involving 30,895 participants. Three studies investigated oral DTIs (two dabigatran and one ximelagatran), 17 investigated oral factor Xa inhibitors (eight rivaroxaban, five apixaban and four edoxaban) and one three-arm trial investigated both a DTI (dabigatran) and factor Xa inhibitor (rivaroxaban). Overall, the studies were of good methodological quality. Meta-analysis comparing DTIs to conventional anticoagulation showed no clear difference in the rate of recurrent VTE (odds ratio (OR) 1.17, 95% confidence interval (CI) 0.83 to 1.65; 3 studies, 5994 participants; moderate-certainty evidence), recurrent DVT (OR 1.11, 95% CI 0.74 to 1.66; 3 studies, 5994 participants; moderate-certainty evidence), fatal PE (OR 1.32, 95% CI 0.29 to 6.02; 3 studies, 5994 participants; moderate-certainty evidence), non-fatal PE (OR 1.29, 95% CI 0.64 to 2.59; 3 studies, 5994 participants; moderate-certainty evidence) or all-cause mortality (OR 0.66, 95% CI 0.41 to 1.08; 1 study, 2489 participants; moderate-certainty evidence). DTIs reduced the rate of major bleeding (OR 0.58, 95% CI 0.38 to 0.89; 3 studies, 5994 participants; high-certainty evidence).   For oral factor Xa inhibitors compared with conventional anticoagulation, meta-analysis demonstrated no clear difference in recurrent VTE (OR 0.85, 95% CI 0.71 to 1.01; 13 studies, 17,505 participants; moderate-certainty evidence), recurrent DVT (OR 0.70, 95% CI 0.49 to 1.01; 9 studies, 16,439 participants; moderate-certainty evidence), fatal PE (OR 1.18, 95% CI 0.69 to 2.02; 6 studies, 15,082 participants; moderate-certainty evidence), non-fatal PE (OR 0.93, 95% CI 0.68 to 1.27; 7 studies, 15,166 participants; moderate-certainty evidence) or all-cause mortality (OR 0.87, 95% CI 0.67 to 1.14; 9 studies, 10,770 participants; moderate-certainty evidence). Meta-analysis showed a reduced rate of major bleeding with oral factor Xa inhibitors compared with conventional anticoagulation (OR 0.63, 95% CI 0.45 to 0.89; 17 studies, 18,066 participants; high-certainty evidence).  AUTHORS' CONCLUSIONS: The current review suggests that DOACs may be superior to conventional therapy in terms of safety (major bleeding), and are probably equivalent in terms of efficacy. There is probably little or no difference between DOACs and conventional anticoagulation in the prevention of recurrent VTE, recurrent DVT, pulmonary embolism and all-cause mortality. DOACs reduced the rate of major bleeding compared to conventional anticoagulation. The certainty of evidence was moderate or high.

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.

Direct oral anticoagulants versus low-molecular-weight heparins for the treatment of acute venous thromboembolism in patients with gastrointestinal cancer: a systematic review and meta-analysis

Background

The association between gastrointestinal (GI) cancer and a high incidence of venous thromboembolism (VTE) is well known. Previous randomized controlled studies demonstrated that direct oral anticoagulants (DOACs) effectively treat cancer-associated thrombosis (CAT). However, some DOACs appeared to increase the risk of bleeding, particularly in patients with GI malignancies. Therefore, the current systematic review and meta-analysis were conducted to evaluate the safety and efficacy of DOACs in GI cancer-associated thrombosis.

Methods

Two investigators individually reviewed all studies that compared DOACs and low-molecular-weight heparins (LMWHs) in GI cancer-associated thrombosis and were published in MEDLINE and EMBASE before February 2022. The effect estimates and 95% confidence intervals (CIs) from each eligible study were combined using the Mantel–Haenszel method.

Results

A total of 2226 patients were included in the meta-analysis. The rates of major bleeding in the DOAC and LMWH groups were not significantly different (relative risk [RR]: 1.31; 95% CI: 0.84–2.04; P = 0.23; I² = 41%). However, the rate of clinically relevant nonmajor bleeding (CRNMB) was significantly higher in the DOAC group (RR: 1.76; 95% CI: 1.24–2.52; P = 0.002; I² = 8%). The risks of recurrent VTE in the groups did not significantly differ (RR: 0.72; 95% CI: 0.49–1.04; P = 0.08; I² = 0%).

Conclusions

The current data suggest that treatment of GI cancer-associated thrombosis with DOACs significantly increases the risk of CRNMB. However, the risk of major bleeding was not significantly different. The efficacy of DOACs for preventing recurrent VTE in GI cancer was comparable to that of LMWHs.

Trial registration

INPLASY202180113.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12959-022-00399-7.