Anti-Inflammatory and Anticancer Effects of Anticoagulant Therapy in Patients with Malignancy

Optimizing the anticoagulation therapy is of pivotal importance in patients with a malignant tumor, as venous thromboembolism (VTE) has become the second-leading cause of death in this population. Cancer can highly increase the risk of thrombosis and bleeding. Consequently, the management of cancer-associated VTE is complex. In recent years, translational research has intensified, and several studies have highlighted the role of inflammatory cytokines in cancer growth and progression. Simultaneously, the pleiotropic effects of anticoagulants currently recommended for VTE have emerged. In this review, we describe the anti-inflammatory and anticancer effects of both direct oral anticoagulants (DOACs) and low-molecular-weight heparins (LWMHs).

Assessment of BMI and Venous Thromboembolism Rates in Patients on Standard Chemoprophylaxis Regimens After Undergoing Free Tissue Transfer to the Head and Neck

Importance

Venous thromboembolism (VTE) is a severe complication after free tissue transfer to the head and neck (H&N). Enoxaparin 30 mg twice daily (BID) is a common regimen for chemoprophylaxis. However, differences in enoxaparin metabolism based on body weight may influence its efficacy and safety profile.

Objective

To assess the association between BMI and postoperative VTE and hematoma rates in patients treated with prophylactic enoxaparin 30 mg BID.

Design, Setting, and Participants

This was a retrospective review of a prospectively collected cohort from 2012 to 2022. Postoperative VTE, hematoma, and free flap pedicle thrombosis were recorded within 30 days of index surgery. The setting was a tertiary academic referral center. Participants included patients undergoing H&N reconstruction with free flaps that received fixed-dose subcutaneous enoxaparin 30 mg BID postoperatively. Statistical analysis was conducted from April to May 2022.

Main Outcomes and Measures

Outcomes include incidence of VTE, hematoma, and flap pedicle thrombosis events within 30 days of the surgery. Univariate and multivariable regression models were used to evaluate associations between BMI and other patient factors with these outcomes.

Results

Among the 765 patients included, 262 (34.24%) were female; mean (SD) age was 60.85 (12.64) years; and mean (SD) BMI was 26.36 (6.29). The rates of VTE and hematoma in the cohort were 3.92% (30 patients) and 5.09% (39 patients), respectively. After adjusting for patient factors, BMI was the only factor associated with VTE (OR, 1.07; 95% CI, 1.015-1.129). Obesity (BMI >30) was associated with increased odds of VTE (OR, 2.782; 95% CI, 1.197-6.564). Hematoma was not associated with BMI (OR, 0.988; 95% CI, 0.937-1.041). Caprini score of at least 9 was not associated with VTE (OR, 1.259; 95% CI, 0.428-3.701).

Conclusions and Relevance

This cohort study found that obesity was associated with an increased risk of VTE in patients after microvascular H&N reconstruction and while on standard postoperative chemoprophylaxis regimens. This association may suggest insufficient VTE prophylaxis in this group and a potential indication for weight-based dosing.

Heparin and related drugs for venous thromboembolism prophylaxis: subcutaneous or intravenous continuous infusion?

In this article, the most evidenced approaches of unfractionated heparin administration for prevention of venous thromboembolism in medical and surgical hospitalized patients will be reviewed. Present data were collected by searching Scopus, PubMed, MEDLINE, Science direct, Clinical trials and Cochrane database systematic reviews. Subcutaneous low doses of unfractionated heparin (10000–15000 IU) in two or three divided doses per day are commonly administrated for venous thromboembolism prevention in different medical and surgical populations. In some populations such as obese surgical and critically ill patients, due to altered pharmacokinetics behavior of unfractionated heparin, continuous intravenous infusion of the low doses of unfractionated heparin has been proposed.

Low molecular weight heparin in prophylaxis of deep vein thrombosis in Asian general surgical patients: A Kashmir experience

BACKGROUND AND OBJECTIVES

Deep vein thrombosis (DVT) occurs at a lower rate in Asia than in the rest of the world. We wanted to study the significance and efficacy of low molecular weight heparin (LMWH) in prophylaxis of DVT in major general surgical patients in the Kashmir Valley (India, Asia) so as to make it a routine in our patients.

PATIENTS AND METHODS

This was a prospective study in which the effect of LMWH was compared with no prophylaxis.

RESULTS

LMWHs are more effective than no prophylaxis in the prevention of DVT and pulmonary thromboembolism in highest-risk general surgical patients (odds ratio = 16.64; 95% confidence interval = 3.63-1130.03; P-value = 0.014).

CONCLUSION

LMWHs have a significant prophylactic effect on DVT in general surgical patients, with a higher benefit to risk ratio, and, in spite of the low incidence of DVT in Asia, its prophylaxis should routinely be considered in this part of the world as well, preferably in the form of LMWHs.

Low molecular weight heparin versus unfractionated heparin for perioperative thromboprophylaxis in patients with cancer

BACKGROUND

The choice of the appropriate perioperative thromboprophylaxis in patients with cancer depends on the relative benefits and harms of low molecular weight heparin (LMWH) and unfractionated heparin (UFH).

OBJECTIVES

To systematically review the evidence for the relative efficacy and safety of LMWH and UFH for perioperative thromboprophylaxis in patients with cancer.

SEARCH METHODS

A comprehensive search for trials of anticoagulation in cancer patients including a February 2010 electronic search of: the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE and ISI Web of Science.

SELECTION CRITERIA

Randomized controlled trials (RCTs) that enrolled cancer patients undergoing a surgical intervention and compared the effects of LMWH to UFH on mortality, deep venous thrombosis (DVT), pulmonary embolism (PE), bleeding outcomes, and thrombocytopenia.

DATA COLLECTION AND ANALYSIS

Two review authors used a standardized form to independently extract in duplicate data on risk of bias, participants, interventions and outcomes of interest. Where possible, we conducted meta-analyses using the random-effects model.

MAIN RESULTS

Of 8187 identified citations, we included 16 RCTs with 11,847 patients in the meta-analyses, all using preoperative prophylactic anticoagulation. The overall quality of evidence was moderate. The meta-analysis did not conclusively rule out either a beneficial or harmful effect of LMWH compared to UFH for the following outcomes: mortality (RR = 0.90; 95% CI 0.73 to 1.10), symptomatic DVT (RR = 0.73; 95% CI 0.23 to 2.28), PE (RR = 0.59; 95% CI 0.25 to1.41), minor bleeding (RR = 0.88; 95% CI 0.47 to 1.66) and major bleeding (RR = 0.84; 95% CI 0.52 to 1.36). LMWH was associated with lower incidence of wound hematoma (RR = 0.60; 95% CI 0.43, 0.84) while UFH was associated with higher incidence of intra-operative transfusion (RR = 1.16; 95% CI 0.69,1.62).

AUTHORS' CONCLUSIONS

We found no difference between perioperative thromboprophylaxis with LMWH verus UFH in their effects on mortality and embolic outcomes in patients with cancer. Further trials are needed to more carefully evaluate the benefits and harms of different heparin thromboprophylaxis strategies in this population.

Thromboembolic Disorders in Cancer

Complex factors, including substances in cancer cells, cancer treatment effects, and venous stasis associated with chronic illness, blood vessel wall injury, and immobility, interact to place patients with cancer at risk for thrombosis. This article describes the etiology, clinical manifestations, diagnostic tests, and treatments for venous and pulmonary emboli associated with cancer. It explores the nurse's role in assessing patients who are at risk, managing symptomatic thrombosis and primary and secondary prevention of emboli, and administering anticoagulant therapy. As growing numbers of patients are treated in outpatient settings, oncology nurses play a critical role in the coordination of care for patients at risk for thrombosis. A nursing care plan summarizes key nursing strategies for assessment and intervention.

Clinical efficacy and safety of fondaparinux in the prevention and treatment of venous and arterial thrombosis

Fondaparinux (Arixtra®) is a synthetic, selective Factor Xa inhibitor. Its pharmacokinetic profile allows once-daily subcutaneous administration of the drug without any laboratory monitoring. The benefit-to-risk ratio of fondaparinux in the prevention of venous thromboembolism has been extensively studied in both surgical and acutely ill medical patients at risk of thrombosis. Its efficacy and safety have also been investigated in the initial treatment of symptomatic deep-vein thrombosis and pulmonary embolism. Finally, a number of Phase II trials investigated the safety and efficacy of fondaparinux in patients with acute coronary syndromes, and a large Phase III program is ongoing in this setting. This review focuses on the use of fondaparinux in the prevention and treatment of thromboembolic disorders.

Management of thrombosis in cancer: primary prevention and secondary prophylaxis

Although traditional anticoagulant regimens are highly effective and safe in most patients with venous thromboembolism (VTE), the aggressive natural history of VTE and the high risk of serious bleeding in cancer patients can complicate the management of VTE. In addition, because few clinical trials have focused on the prevention and treatment of VTE in this unique patient population, many clinical questions regarding the care of cancer patients with VTE remain unanswered. Currently, low-molecular-weight heparins and oral vitamin K antagonists are the most commonly used agents for the primary and secondary prophylaxis of VTE in patients with or without cancer, but their use is associated with pharmacological and practical limitations. This review will provide an up-to-date summary of the clinical trials that have addressed the management of VTE in patients with cancer. A brief discussion of the potential application of novel anticoagulants in these clinical settings is also included.

Fondaparinux: an update on new study results

Fondaparinux (Arixtra) is the first selective factor Xa inhibitor approved for use in thromboprophylaxis after orthopaedic surgery. New recently completed trials have also demonstrated the potential of fondaparinux in the prevention of venous thromboembolism (VTE) in other surgical and medical settings and in the treatment of established VTE. In the randomized double-blind PEGASUS study in high-risk abdominal surgery patients, fondaparinux reduced the incidence of VTE from 6.1% with dalteparin to 4.6% (odds ratio reduction = 25.8%, P = 0.14), without increasing the bleeding risk. In the randomized double-blind ARTEMIS trial in acutely ill medical patients, fondaparinux reduced the incidence of VTE from 10.5% with placebo to 5.6% (odds ratio reduction = 49.5%, P = 0.029), without increasing the bleeding risk; there was no pulmonary embolism in the fondaparinux group compared with five, all fatal, in the placebo group (P = 0.029). In the two MATISSE trials, both the efficacy and safety of once daily fondaparinux were at least as good as enoxaparin in the treatment of deep-vein thrombosis (MATISSE-DVT) and unfractionated heparin in the treatment of pulmonary embolism (MATISSE-PE). In patients with coronary artery disease, promising results were obtained in phase II trials and large phase III trials are ongoing. In conclusion, fondaparinux may further improve and simplify the prevention and treatment of thrombosis in a large range of medical and surgical settings.

Cancer, thrombosis, and anticoagulants

Rapid progress has been made recently in our understanding of the pathogenesis of coagulation activation in malignancy and mechanisms by which the coagulation mechanism may control malignant growth. Idiopathic thromboembolic disease may be the sentinel presentation in patients subsequently diagnosed with malignancy. Thrombosis complicating the course of malignancy may be notoriously difficult to treat, but the introduction of the low-molecular-weight heparins has greatly improved management and may obviate the need for invasive approaches, such as the use of inferior vena cava filters, in many cases. Tantalizing clues from clinical trials of anticoagulant therapy in cancer have suggested that components of coagulation pathways may support tumor growth. Many of these can be intercepted using drugs that are well known and non-toxic. The importance of performing high-quality controlled clinical trials that build on past studies and on data from basic research cannot be overemphasized.