Efficacy and safety of direct oral anticoagulants vs. low molecular weight heparin for cancer-related venous thromboembolism: a meta-analysis of randomized trials

Direct oral anticoagulants (DOACs) versus low-molecular-weight heparin (LMWH) for extended thromboprophylaxis following major abdominal/pelvic cancer-related surgery: a systematic review and meta-analysis

BACKGROUND

The use of direct oral anticoagulants (DOACs) as an alternative to low-molecular-weight heparin (LMWH) for extended thromboprophylaxis of abdominal/pelvic cancer-related postoperative thromboembolism (VTE) is unclear. We aim to investigate the efficacy and safety of DOACs vs. LMWH in these patients.

METHODS

A systematic review was conducted using EMBASE, MEDLINE, CENTRAL, and Web of science through May 19th, 2023 for all randomized controlled trials (RCTs) and observational studies that compared the outcomes with DOACs vs. LMWH for extended thromboprophylaxis among patients undergoing abdominal/pelvic cancer surgery. Primary efficacy outcome was clinical VTE, and safety outcome was clinically relevant bleeding complications reported within the 30-day postoperative period. This study was registered in PROSPERO (CRD42023413175).

RESULTS

We identified 5078 articles and selected 29 full-text articles for eligibility. A total of 9 studies (2 RCTs and 7 observational studies) encompassing 2651 patients were included for systematic review and 7 for meta-analysis. When compared with LMWH extended thromboprophylaxis, DOACs had a similar incidence of VTE (RR: 0.65 [95% CI: 0.32-1.33], I2 = 0%), major bleeding (RR: 1.68 [95% CI: 0.36-7.9], I2 = 26%), and clinically relevant non-major bleeding (RR: 0.68 [95% CI: 0.39-1.19], I2 = 0%). Subgroup analysis suggested no difference according to the study type (RCTs versus observational studies) regarding clinical VTE or major bleeding (Pinteraction = 0.43 and Pinteraction = 0.71, respectively).

CONCLUSION

Our results suggest that DOACs for extended thromboprophylaxis were an effective and safe alternative to LMWH after major abdominal/pelvic cancer-related surgery.

Efficacy and safety of direct oral anticoagulants versus low-molecular-weight heparin for thromboprophylaxis after cancer surgery: a systematic review and meta-analysis

BACKGROUND

Direct oral anticoagulants (DOACs) used as an alternative to low-molecular-weight heparin (LMWH) for thromboprophylaxis after cancer surgery for venous thromboembolic events (VTE) remains unclear. This study aimed to investigate the efficacy and safety of DOACs versus LMWH in these patients.

MATERIALS AND METHODS

A search of EMBASE, MEDLINE, Cochrane Central Register of Controlled Trials (CENTRAL), and Web of Science was carried out and included all randomized controlled trials (RCTs) and observational studies that directly compared DOACs with LMWH for thromboprophylaxis in patients after cancer surgery through July 25, 2023. The primary efficacy and safety outcomes were VTE, major bleeding, and clinically relevant non-major bleeding (CRNMB) within 30 days of surgery. The risk of bias was assessed using the Cochrane Risk of Bias 2 (RoB2) tool for RCTs and ROBINS-I tool for non-randomized studies. This study was registered in PROSPERO (CRD42023445386).

RESULTS

We retrieved 5149articles, selected 27 for eligibility, and included 10 studies (three RCTs and seven observational studies) encompassing 3054 patients who underwent postoperative thromboprophylaxis with DOACs (41%) or LMWH (59%). Compared to LMWH thromboprophylaxis, DOACs had a comparable risk of VTE (RR:0.69[95% CI:0.46-1.02], I2 = 0%), major bleeding (RR:1.55 [95% CI:0.82-2.93], I2 = 2%), and CRNMB (RR, 0.89 [95% CI, 0.4-1.98], I2 = 31%) during the 30-day postoperative period. Subgroup analysis of VTE and major bleeding suggested no differences according to study type, extended thromboprophylaxis, tumor types, or different types of DOAC.

CONCLUSION

DOACs are potentially effective alternatives to LMWH for thromboprophylaxis in patients undergoing cancer surgery, without increasing the risk of major bleeding events.

DOAC in the treatment of cancer-associated venous thromboembolism: a retrospective cohort study beyond the guidelines

BACKGROUND

The emerging use of direct oral anticoagulants (DOAC) in the management of cancer-associated venous thromboembolism (CAT) is significantly improving therapeutic adherence and quality of life. Despite this, many conditions can restrict the therapeutic index of these drugs. For all these reasons the latest guidelines recommend the use of heparins in the treatment of CAT as the preferred treatment in some clinical settings.

OBJECTIVES

We evaluated the efficacy and the safety of DOAC, in terms of recurrent venous thromboembolism (VTE) and major bleeding (MB), as a composite primary outcome. Mortality and clinically relevant non-major bleeding (CRNMB) were evaluated as secondary outcomes.

METHODS

We performed a retrospective study on 209 patients to compare the effects of DOAC versus heparins for the treatment of CAT. 127 patients with a high bleeding risk neoplasia were enrolled.

RESULTS

A primary-outcome event occurred in 11.3% of patients treated with heparins and in 10.5% treated with DOAC (Relative Risk 0.92; 95% CI 0.42-2.01, p = 0.84). Recurrent VTE occurred in 6.1% in the heparins group and in 8.4% in the DOAC group (RR 1.37; 95% CI 0.51-3.64, p = 0.52). MB occurred in 5.2% in the heparins group and in 2.1% in the DOAC group (RR 0.40; 95% CI 0.08-1.93, p = 0.25).

CONCLUSIONS

DOAC seem to be as effective and safe as heparins in the treatment of CAT. Most bleeding events occurred in patients with high-risk bleeding neoplasms regardless of the type of anticoagulant. Considering the characteristics and satisfaction of patients using DOAC in this setting, this approach should be considered as a first choice.

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.

2022 international clinical practice guidelines for the treatment and prophylaxis of venous thromboembolism in patients with cancer, including patients with COVID-19

The International Initiative on Thrombosis and Cancer is an independent academic working group of experts aimed at establishing global consensus for the treatment and prophylaxis of cancer-associated thrombosis. The 2013, 2016, and 2019 International Initiative on Thrombosis and Cancer clinical practice guidelines have been made available through a free, web-based mobile phone application. The 2022 clinical practice guidelines, which are based on a literature review up to Jan 1, 2022, include guidance for patients with cancer and with COVID-19. Key recommendations (grade 1A or 1B) include: (1) low-molecular-weight heparins (LMWHs) for the initial (first 10 days) treatment and maintenance treatment of cancer-associated thrombosis; (2) direct oral anticoagulants for the initial treatment and maintenance treatment of cancer-associated thrombosis in patients who are not at high risk of gastrointestinal or genitourinary bleeding, in the absence of strong drug-drug interactions or of gastrointestinal absorption impairment; (3) LMWHs or direct oral anticoagulants for a minimum of 6 months to treat cancer-associated thrombosis; (4) extended prophylaxis (4 weeks) with LMWHs to prevent postoperative venous thromboembolism after major abdominopelvic surgery in patients not at high risk of bleeding; and (5) primary prophylaxis of venous thromboembolism with LMWHs or direct oral anticoagulants (rivaroxaban or apixaban) in ambulatory patients with locally advanced or metastatic pancreatic cancer who are treated with anticancer therapy and have a low risk of bleeding.

Emergency department cardiovascular disease encounters and associated mortality in patients with cancer: A study of 20.6 million records from the USA

BACKGROUND

there is limited data on Emergency department (ED) cardiovascular disease (CVD) presentations and outcomes amongst cancer patients.

OBJECTIVES

The present study aimed to describe the clinical characteristics, prevalence, and clinical outcomes of the most common cardiovascular ED admissions in patients with cancer.

METHODS

All ED encounters with a primary CVD diagnosis from the US Nationwide Emergency Department Sample between January 2016 to December 2018 were stratified by cancer type as well as metastatic status. Multivariable logistic regression was performed to determine the adjusted odds ratios of in-hospital mortality in different groups.

RESULTS

From a total of 20,737,247 ED encounters with a primary CVD diagnosis, cancer was present in 3.4%. In patients with cancer the most common CVDs were DVT/PE (20%), hypertensive heart or kidney disease (14.7%), and AF/flutter (11.2%). The distribution of CVDs varied by cancer type, with AF/flutter most common in patients with lung cancer, AMI most common in patients with prostate cancer, heart failure most common in those with haematological malignancies, and patients with colorectal cancer having the greatest frequency of DVT/PE. Cancer status was independently associated with significantly higher risk of mortality in almost all CVD categories, consistent across all the cancer types, amongst which lung cancer patients had the highest risk of mortality across all CVD categories, except intracranial haemorrhage and hypertensive crisis.

CONCLUSIONS

Cardiovascular presentations to the ED varied by cancer subtype. Across all cancer subtypes, patients presenting with cardiovascular presentations carried a significantly increased risk of mortality compared to patients with no cancer.

Application Effect of the Standard Operating Procedure in the Prevention of Venous Thromboembolism

OBJECTIVE

To investigate the application effect of the standard operating procedure (SOP) in the prevention of venous thromboembolism (VTE).

METHODS

The clinical data of patients admitted to respiratory, cardiovascular, neurological, and geriatric departments in the hospital (November 2020-May 2021) were retrospectively analyzed, and the patients in line with the inclusion criteria were equally randomized into the observation group (OG) and the control group (CG). The CG was treated with the routine nursing, and the OG received the SOP of VTE prevention additionally. After the record of the incidence of VTE and nursing satisfaction of the two groups, scores of VTE awareness were compared.

RESULTS

One hundred and twenty patients were included in this study, and no obvious difference was found in the general data of patients (P > 0.05). Compared with the CG, the incidence of VTE of the OG was obviously lower (P < 0.05). After nursing, compared with the CG, scores of VTE awareness in the OG were conspicuously higher (P < 0.001), and scores of VTE awareness of the nursing staff were conspicuously higher than those before nursing (P < 0.001). Compared with the CG, nursing satisfaction of the OG was obviously higher (P < 0.001).

CONCLUSION

SOP can reduce the incidence of VTE of patients, improve their disease awareness, and enhance their nursing satisfaction, which should be popularized in practice.

An epidemic of redundant meta-analyses

BACKGROUND

Meta-analyses are widely used to strengthen available evidence and obtain more precise estimates of treatment effect than any individual trial. Paradoxically, multiplication of meta-analyses on the same topic can lead to confusion as practitioners no longer benefit from a rapid and synthetic response. This phenomenon may appear disproportionate when the number of published meta-analyses exceeds the number of original studies.

OBJECTIVES

To describe an example of redundant meta-analyses published in the same area with the same randomized clinical trials (RCTs).

METHODS

A systematic review was performed to identify all published meta-analyses of original RCTs that compared direct oral anticoagulants with low molecular weight heparins in cancer patients with venous thromboembolism (VTE). Forest plots were used to represent the meta-analyses results for efficacy (VTE recurrence) and safety (major bleeding) endpoints. An authors' network was constructed to explore the links between the authors of the published meta-analyses.

RESULTS

In the past 3 years, four original RCTs were the subject of 20 published meta-analyses by 142 authors: five, four, and 11 meta-analyses pooled the data of two, three, and four RCTs, respectively. The results of meta-analyses were similar regarding the risks of VTE recurrence and major bleeding. The 11 meta-analyses of four RCTs were published within 6 months of the publication of the last RCT.

CONCLUSIONS

The epidemic proportions of such redundant literature and authorship could be moderated by developing "living" meta-analyses and encouraging authors of new RCTs to update the corresponding meta-analysis in the same paper as their original research.

Current status of treatment of cancer-associated venous thromboembolism

Patients with cancer are prone to develop venous thromboembolism (VTE) that is the second leading cause of mortality among them. Cancer patients with VTE may encounter higher rates of VTE recurrence and bleeding complications than patients without cancer. Treatment of established VTE is often complex in patients with cancer. Treatment of cancer-associated VTE basically comprises initial treatment, long-term treatment, treatment within 6 months, treatment beyond 6 months, treatment of recurrent VTE, and treatment in special situations. Decision of antithrombotic therapy, selection of anticoagulants, duration of anticoagulation, decision of adjuvant therapy, and adjustment of regimen in special situations are the major problems in the treatment of cancer-associated VTE. Therapeutic anticoagulation is the key of the key in the treatment of cancer-associated VTE. In addition to the efficacy and safety of low-molecular-weight heparin (LMWH) that has been fully demonstrated, direct oral anticoagulants (DOACs) are increasingly showing its advantages along with the accompanying concern in the treatment of cancer-associated VTE. The latest ASCO, ITAC and NCCN guidelines agree with each other on most aspects with respect to the treatment of cancer-associated VTE, whereas differ on a few issues. Encompassing recent randomized controlled trials, clinical trials, and meta-analyses, as well as the comparison of the latest authoritative guidelines including the NCCN, ASCO, and ITAC guidelines in this field, the objective of this review is to present current overview and recommendations for the treatment of cancer-associated VTE.