Long-Term Treatment of Cancer-Associated Thrombosis (CAT) Beyond 6 Months in the Medical Practice: USCAT, a 432-Patient Retrospective Non-Interventional Study

Comparison of Clinical Outcomes in Patients with Active Cancer Receiving Rivaroxaban or Low-Molecular-Weight Heparin: The OSCAR-UK Study

BACKGROUND

 In most patients with cancer-associated venous thromboembolism (CT), essentially those not at high risk of bleeding, guidelines recommend treatment with direct oral anticoagulants as an alternative to low-molecular-weight heparins (LMWHs). Population-based studies comparing these therapies are scarce.

OBJECTIVES

 To compare the risk of venous thromboembolism (VTE) recurrences, significant bleeding, and all-cause mortality in patients with CT receiving rivaroxaban or LMWHs.

PATIENTS/METHODS

 Using UK Clinical Practice Research Datalink data from 2013 to 2020, we generated a cohort of patients with first CT treated initially with either rivaroxaban or LMWH. Patients were observed 12 months for VTE recurrences, significant bleeds (major bleeds or clinically relevant nonmajor bleeding requiring hospitalization), and all-cause mortality. Overlap weighted sub-distribution hazard ratios (SHRs) compared rivaroxaban with LMWH in an intention-to-treat analysis.

RESULTS

 The cohort consisted of 2,259 patients with first CT, 314 receiving rivaroxaban, and 1,945 LMWH, mean age 72.4 and 66.9 years, respectively. In the 12-month observational period, 184 person-years following rivaroxaban and 1,057 following LMWH, 10 and 66 incident recurrent VTE events, 20 and 102 significant bleeds, and 10 and 133 deaths were observed in rivaroxaban and LMWH users, respectively. The weighted SHR at 12 months for VTE recurrences in rivaroxaban compared with LMWH were 0.80 (0.37-1.73); for significant bleeds 1.01 (0.57-1.81); and for all-cause mortality 0.49 (0.23-1.06).

CONCLUSION

 Patients with CT, not at high risk of bleeding, treated with either rivaroxaban or LMWH have comparable effectiveness and safety outcomes. This supports the recommendation that rivaroxaban is a reasonable alternative to LMWH for the treatment of CT.

[Translation into French and republication of: "Anticoagulant treatment of cancer-associated thromboembolism"]

Venous thromboembolism (VTE) is a frequent and potentially fatal complication in patients with cancer. During the initial period after the thromboembolic event, a patient receiving anticoagulant treatment is exposed both to a risk of VTE recurrence and also to an elevated bleeding risk conferred by the treatment. For this reason, the choice of anticoagulant is critical. The choice should take into account patient-related factors (such as functional status, age, body mass index, platelet count and renal function), VTE-related factors (such as severity or site), cancer-related factors (such as activity and progression) and treatment related factors (such as drug-drug interactions), which all potentially influence bleeding risk, and patient preference. These should be evaluated carefully for each patient during a multidisciplinary team meeting. For most patients, apixaban or a low molecular-weight heparin is the most appropriate initial choice for anticoagulant treatment. Such treatment should be offered to all patients with active cancer for at least 6months. The patient and treatment should be re-evaluated regularly, and anticoagulant treatment changed when necessary. Continued anticoagulant treatment beyond 6months is justified if the cancer remains active or if the patient experienced recurrence of VTE in the first 6months. In other cases, the interest of continued anticoagulant treatment may be considered on an individual patient basis in collaboration with oncologists.

Anticoagulant treatment of cancer-associated thromboembolism

Venous thromboembolism (VTE) is a frequent and potentially fatal complication in patients with cancer. During the initial period after the thromboembolic event, a patient receiving anticoagulant treatment is exposed both to a risk of VTE recurrence and also to an elevated bleeding risk conferred by the treatment. For this reason, the choice of anticoagulant is critical. The choice should take into account patient-related factors (such as functional status, age, body mass index, platelet count and renal function), VTE-related factors (such as severity or site), cancer-related factors (such as activity and progression) and treatment-related factors (such as drug-drug interactions), which all potentially influence bleeding risk, and patient preference. These should be evaluated carefully for each patient during a multidisciplinary team meeting. For most patients, apixaban or a low molecular-weight heparin is the most appropriate initial choice for anticoagulant treatment. Such treatment should be offered to all patients with active cancer for at least six months. The patient and treatment should be re-evaluated regularly and anticoagulant treatment changed when necessary. Continued anticoagulant treatment beyond six months is justified if the cancer remains active or if the patient experienced recurrence of VTE in the first six months. In other cases, the interest of continued anticoagulant treatment may be considered on an individual patient basis in collaboration with oncologists.

French guidelines for the treatment of cancer-associated venous thromboembolism - 2023 update

BACKGROUND

In recent years, knowledge about cancer associated thrombosis has evolved considerably.

METHODS

Practical guidelines were drafted on the initiative of the INNOVTE FCRIN Network, led by the French Speaking Society of Respiratory Diseases (SPLF), by a coordinating group, a writing group, and a review group, with the involvement of different scientific societies practicing in various settings. The method followed the "Clinical Practice Guidelines" process of the French National Authority for Health (HAS).

RESULTS

After a literature review, guidelines were formulated, improved, and then validated by the working groups. These guidelines addressed multiple aspects of the disease and management from the data of available clinical trials and observational studies : epidemiology, initial treatment, treatment duration, extended treatment, recurrent thrombosis, central venous catheter thrombosis, incidental thrombosis, treatment in case of thrombocytopenia.

CONCLUSION

These evidence-based guidelines are intended to guide the practical management of patients with cancer associated thrombosis.

The risk of recurrent venous thromboembolism after discontinuation of anticoagulant therapy in patients with cancer-associated thrombosis: a systematic review and meta-analysis

Background

The optimal duration of anticoagulation in patients with active cancer and venous thromboembolism (VTE) is unknown. Current clinical guidelines advocate anticoagulant therapy for 3-6 months and to continue anticoagulant therapy for as long as the cancer is active. However, an adequate systematic review on the rate of recurrent VTE after discontinuation of anticoagulant therapy has not been performed.

Methods

For this systemic review and meta-analysis, we searched Embase.com, Medline (Ovid), Web of Science, Cochrane Library, and Google Scholar, from database inception to February 16, 2023, for studies on anticoagulant therapy in patients with cancer and the recurrence of venous thromboembolism after discontinuation of this therapy. We included randomised controlled trials and cohort studies published in English that reported on patients who met the following: cancer and a first VTE, completed at least 3 months of anticoagulant therapy, were followed after discontinuation of anticoagulant therapy, and with symptomatic recurrent VTE as an outcome during follow-up. Study-level data were requested from study authors. The primary outcome was the rate of recurrent VTE after discontinuation of anticoagulant therapy. A Bayesian random-effects meta-analysis was used to estimate the rate of recurrent VTE per 100 person-years for the pooled studies at different time intervals after discontinuation of anticoagulation therapy. We also calculated the cumulative VTE recurrence rate at different time intervals. Forest plots were mapped and the results were summarized by the median and 95% credible interval (CIs). This study was registered with PROSPERO, CRD42021249060.

Findings

Of 3856 studies identified in our search, 33 studies were identified for inclusion. After requesting study-level data, 14 studies involving 1922 patients with cancer-associated thrombosis were included. The pooled rate of recurrent VTE per 100 person-years after discontinuation of anticoagulant therapy was 14.6 events (95% credible interval 6.5-22.8) in the first three months, decreasing to 1.1 events (95% CI 0.3-2.1) in year 2-3, and 2.2 events (95% CI 0.0-4.4) in year 3-5 after discontinuation of anticoagulant therapy. The cumulative VTE recurrence rate was 28.3% (95% CI 15.6-39.6%) at 1 year; 31.1% (95% CI 16.5-43.8%) at 2 years; 31.9% (95% CI 16.8-45.0%) at 3 years; and 35.0% (95% CI 16.8-47.4%) at 5 years after discontinuation of anticoagulant therapy.

Interpretation

This meta-analysis demonstrates a high rate of recurrent VTE over time after discontinuation of anticoagulant therapy in patients with cancer-associated thrombosis. Our results support the current clinical guidelines to continue anticoagulant therapy in patients with active cancer.

Funding

Erasmus MC.

Adult breast, lung, pancreatic, upper and lower gastrointestinal cancer patients with hospitalized venous thromboembolism in the national French hospital discharge database

BACKGROUND

Venous thromboembolism (VTE) and cancer are strongly associated. In France, evidence on patients with pancreatic, upper GI [gastrointestinal], lower GI, lung, or breast cancer-associated VTE and their hospital management is limited. The aims of this study were to provide data on the number of hospitalized VTE events among cancer patients, the patients' characteristics, and their hospital management to estimate the burden of disease and the hospital burden of cancer-related VTE and to provide guidance on research.

METHODS

This longitudinal, observational, and retrospective study was based on the comprehensive hospital discharge database (PMSI). Adult patients (≥ 18 years old) hospitalized with a cancer of interest in 2016 and hospitalized (within 2 years with VTE (captured a as a principal, related, or significant associated diagnosis) were included in the study.

RESULTS

We identified 340,946 cancer patients, of which 7.2% (24,433 patients) were hospitalized with VTE. The proportions of hospitalized VTE were 14.6% (3,237) for patients with pancreatic cancer, 11.2% (8,339) for lung cancer, 9.9% (2,232) for upper GI cancer, 6.7% (7,011) for lower GI cancer, and 3.1% (3,614) for breast cancer. Around two thirds of cancer patients with a hospitalized VTE had active cancer (with metastases and/or receiving chemotherapy during the six months prior to the index date): from 62% of patients with pancreatic cancer to 72% with breast cancer. Around a third of patients were admitted to the hospital through the emergency room, up to 3% of patients stayed in an intensive care unit. The average length of stay ranged from 10 (breast cancer) to 15 days (upper GI cancer). Nine (lower GI cancer) to 18% (pancreatic cancer) of patients died during the VTE hospital stay.

CONCLUSIONS

The burden of cancer-associated VTE is substantial, both in terms of the number of patients affected and in the hospital use. These findings offer guidance on future research on VTE prophylaxis in a very high-risk population, particularly in patients with active cancer.

Low Molecular Weight Heparin Treatment Patterns and Outcomes in Cancer Patients with Acute Venous Thromboembolism: A Nationwide Cohort Study in France

Patients with cancer have an increased risk of developing venous thromboembolism (VTE) and an increased risk of death from VTE. Until recently, the standard of care for treatment of VTE in cancer patients was low molecular weight heparins (LMWH). To determine treatment patterns and outcomes, we performed an observational study using a nationwide health database. Treatment patterns, rates of bleeding, and VTE recurrence at 6 and 12 months were assessed in cancer patients with VTE in France prescribed LMWH in 2013-2018. Of 31,771 patients administered LMWH (mean age 66.3 years), 51.0% were male, 58.7% had pulmonary embolism, and 70.9% had metastatic disease. At 6 months LMWH persistence was 81.6%, VTE recurrence had occurred in 1256 patients (4.0%) at a crude rate per 100 person-months (PM) of 0.90, and bleeding had occurred in 1124 patients (3.5%) at a crude rate per 100 PM of 0.81. At 12 months, VTE recurrence had occurred in 1546 patients (4.9%) at a crude rate per 100 PM of 0.71 and bleeding had occurred in 1438 patients (4.5%) at a crude rate per 100 PM of 0.66. Overall, VTE-related clinical event rates were high among patients administered LMWH, suggesting an unmet medical need.

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.

Consensus on prevention and treatment of cancer-associated thrombosis (CAT) in controversial clinical situations with low levels of evidence

BACKGROUND

Cancer patients suffer high risk of venous thromboembolism (VTE). Cancer-associated VTE (CAT) causes hospitalization, morbidity, delayed cancer treatment, and mortality; therefore, exceptional CAT prevention and management are imperative.

METHODS

This review offers practical recommendations and treatment algorithms for eight complex, clinically relevant situations posing great uncertainty regarding management and requiring an urgent decision: VTE prophylaxis in ambulatory cancer patients with pancreatic pancreas (1) or lung cancer with molecular alterations (2); optimal management of VTE during antineoplastic treatment with antiangiogenics (3) or chemotherapy (4); protracted VTE treatment, determinants; (5) drugs used (6), and optimal VTE management in situations of high bleeding risk (7) or recurrent VTE (8).

RESULTS

With the evidence available, primary thromboprophylaxis in patients with lung cancer harbouring ALK/ROS1 translocations or pancreatic cancer receiving ambulatory chemotherapy must be appraised. If antiangiogenic therapy can yield a clear benefit and the patient recovers from a grade 3 thrombotic event, it can be cautiously re-introduced in selected cases, provided that the person agrees to assume the risk after being duly informed. Anticoagulation maintenance beyond 6 months is recommended in individuals with metastatic tumours, on active treatment, or at high risk for recurrent VTE without bleeding risk. In such cases, LMWH and DOACs are safe, being mindful that the latter could entail a higher risk of bleeding; consequently, they should be used judiciously in more haemorrhagic tumours, such as gastrointestinal cancers. In cases of recurrent VTE, the presence of active cancer, infra-therapeutic dose, and anticoagulant treatment failure must be ruled out. In individuals with platelet counts of 25,000-50,000 and VTE liable to recur who need anticoagulation, full-dose LMWH and transfusion support can be contemplated to reach values of > 50,000. In CAT unlikely to recur, decreasing the LMWH dose by 25-50% is recommended. Renal impairment associated with thrombosis must be treated with LMWHs; there is no need to adjust the dose in patients with CrCl > 30; with CrCl = 15-30, dose adjustment is advised, and suspended when CrCl is < 15.

CONCLUSION

We provide useful advice for complex, clinically relevant situations that clinicians treating CAT must face devoid of any unequivocal, strong, evidence-based recommendations.

Unanswered questions in cancer-associated thrombosis

Cancer-associated venous thromboembolism (VTE) is a leading cause of morbidity and mortality in patients with cancer. Treatment of cancer-associated VTE comes with a heightened risk of anticoagulant-related bleeding that differs by choice of anticoagulant as well as by patient- and disease-specific risk factors. Available data from randomized controlled trials and observational studies in cancer-associated VTE suggest that direct oral anticoagulants are effective, continuing anticoagulation beyond six months is indicated in those with active cancer and that patients who develop 'breakthrough' thrombotic events can be effectively treated. We review the evidence that addresses these key clinical questions and offer pragmatic approaches in individualizing care. While significant investigative efforts over the past decade have made impactful advances, future research is needed to better define the factors that contribute to anticoagulant-related bleeding and VTE recurrence, in order to aid clinical decision-making that improves the care of patients with cancer-associated VTE.

Extended Anticoagulant Treatment with Full- or Reduced-Dose Apixaban in Patients with Cancer-Associated Venous Thromboembolism: Rationale and Design of the API-CAT Study

Cancer-associated thrombosis (CT) is associated with a high risk of recurrent venous thromboembolic (VTE) events that require extended anticoagulation in patients with active cancer, putting them at risk of bleeding. The aim of the API-CAT study (NCT03692065) is to assess whether a reduced-dose regimen of apixaban (2.5 mg twice daily [bid]) is noninferior to a full-dose regimen of apixaban (5 mg bid) for the prevention of recurrent VTE in patients with active cancer who have completed ≥6 months of anticoagulant therapy for a documented index event of proximal deep-vein thrombosis and/or pulmonary embolism. API-CAT is an international, randomized, parallel-group, double-blind, noninferiority trial with blinded adjudication of outcome events. Consecutive patients are randomized to receive apixaban 2.5 or 5 mg bid for 12 months. The primary efficacy outcome is a composite of recurrent symptomatic or incidental VTE during the treatment period. The principal safety endpoint is clinically relevant bleeding, defined as a composite of major bleeding or nonmajor clinically relevant bleeding. Assuming a 12-month incidence of the primary outcome of 4% with apixaban and an upper limit of the two-sided 95% confidence interval of the hazard ratio <2.0, 1,722 patients will be randomized, assuming an up to 10% loss in total patient-years (β = 80%; α one-sided = 0.025). This trial has the potential to demonstrate that a regimen of extended treatment for patients with CT beyond an initial 6 months, with a reduced apixaban dose, has an acceptable risk of recurrent VTE recurrence and decreases the risk of bleeding.

Extended anticoagulation treatment for cancer-associated thrombosis-Rates of recurrence and bleeding beyond 6 months: A systematic review

BACKGROUND

Patients with cancer-associated venous thromboembolism (VTE) are recommended to receive treatment with therapeutic anticoagulation for at least 3-6 months. Little data exist on extended treatment beyond 6 months.

OBJECTIVE

To comprehensively summarize the best available evidence on incidence of recurrent VTE and major bleeding 6-12 months after the index event in patients with cancer-associated VTE.

PATIENTS/METHODS

We systematically screened biomedical databases (MEDLINE, Embase, CENTRAL) to identify studies reporting recurrent VTE and/or bleeding events between 6 and 12 months after a diagnosis of cancer-associated VTE. Based on the observed heterogeneity in study design, setting, patient cohort characteristics, anticoagulation strategies, and outcome rates, no overall quantitative estimate of outcome rates was calculated.

RESULTS

We screened 2597 publications and identified 11 eligible studies matching predefined in-/exclusion criteria, reporting on 3019 patients specifically during the 6- to 12-month period post-index VTE. Overall rates of recurrent VTE in this timeframe varied substantially (1%-12%), with the highest risk observed in the patient subgroup with residual vein thrombosis present at 6 months randomized to receive no anticoagulation (13%-15%). Reported rates of major bleeding between 6 and 12 months were between 2% and 5%.

CONCLUSIONS

In this systematic review, we provide a comprehensive and structured summary of the best available evidence on recurrence and bleeding risk between 6 and 12 months after cancer-associated VTE. VTE recurrence remains common beyond 6 months and continuation of different anticoagulation strategies has an acceptable safety profile indicated by lower bleeding rates. These findings support guideline recommendations to continue anticoagulation treatment beyond 6 months in patients with active cancer.

Cancer-Associated Thrombosis: Not All Low-Molecular-Weight Heparins Are the Same, Focus on Tinzaparin, A Narrative Review

Cancer-associated thrombosis (CAT) is the second main cause of cancer death with high related mortality and morbidity, leading to anticancer agent delays and interruptions. The recommended therapy, low-molecular-weight heparin (LMWH), however, is burdensome for patients and costly for society, as treatment should last until cancer is no longer active, even indefinitely. Tinzaparin is a manageable, efficient, safe, and cost-effective option. Compared to the other LMWHs, advantages are single-daily dose and safety in the elderly and those with renal impairment (RI). The purpose of this review is to critically discuss recent data on its efficacy and safety in CAT.

Incidence, risk factors, and management of bleeding in patients receiving anticoagulants for the treatment of cancer-associated thrombosis

Updated clinical practice guidelines recommend the long-term use of low-molecular-weight heparins or direct oral anticoagulants as the preferred option for the treatment of cancer-associated thrombosis (CAT), using a personalized approach matching the right drug to the right patient. In most cases, the benefit of anticoagulant therapy outweighs the risk. However, the long-term use of anticoagulants is associated with a non-negligible risk of bleeding, which constitutes a rare but serious adverse effect. Bleeding complications have been reported to be overall 2 to 3 times more frequent in cancer patients with CAT receiving anticoagulation than in non-cancer patients, with a reported incidence of major bleeding ranging from 2.4 to 16.0% in randomized controlled trials (RCT). In the absence of validated risk assessment model to predict the risk of bleeding in these patients, a careful evaluation of each individual profile, with adequate selection of the most appropriate anticoagulant for each individual patient, is warranted for overcoming management challenges, taking in account the numerous factors which may potentiate the overall bleeding risk in these complex patients, such as advanced or metastatic disease, older age, anemia, thrombocytopenia, renal impairment, liver dysfunction, and concomitant anticancer therapies. The purpose of this review is to call for awareness on bleeding complications as a major safety issue of CAT treatment and to summarize data from recent RCT and real-world studies on the incidence and risk factors for bleeding in this unique and challenging population to further help clinicians in decision-making.

Challenging anticoagulation cases: A case of incidental subsegmental pulmonary embolism in a patient with cancer

Cancer therapy and progress in quality of imaging technologies for cancer surveillance and staging are in cause for the increase incidence of smaller incidental pulmonary embolism (PE). The clinical significance of incidental subsegmental pulmonary embolism (SSPE) is hard to define, balancing between possible false positive result, hypercoagulability signal, and truly venous thromboembolism (VTE) event. Evidence for optimal management of such findings are largely extrapolated from symptomatic SSPE in non-cancer patients and from symptomatic, more proximal PE in cancer patients. Current practice guidelines vary but some suggest withholding anticoagulation in selected patients. However, most SSPEs, incidental or not, should be treated as any other cancer-associated PE due to likely similar prognosis. Choice and duration of anticoagulation are extended from existing knowledge on more proximal PE.