Treatment and Prevention of Cancer-Associated Thrombosis in Frail Patients: Tailored Management

[Translation into French and republication of: "Management of cancer-associated thromboembolism in vulnerable population"]

Although all patients with cancer-associated thrombosis (CAT) have a high morbidity and mortality risk, certain groups of patients are particularly vulnerable. This may expose the patient to an increased risk of thrombotic recurrence or bleeding (or both), as the benefit-risk ratio of anticoagulant treatment may be modified. Treatment thus needs to be chosen with care. Such vulnerable groups include older patients, patients with renal impairment or thrombocytopenia, and underweight and obese patients. However, these patient groups are poorly represented in clinical trials, limiting the available data on which treatment decisions can be based. Meta-analysis of data from randomised clinical trials suggests that the relative treatment effect of direct oral factor Xa inhibitors (DXIs) and low molecular weight heparin (LMWH) with respect to major bleeding could be affected by advanced age. No evidence was obtained for a change in the relative risk-benefit profile of DXIs compared to LMWH in patients with renal impairment or of low body weight. The available, albeit limited, data do not support restricting the use of DXIs in patients with TAC on the basis of renal impairment or low body weight. In older patients, age is not itself a critical factor for choice of treatment, but frailty is such a factor. Patients over 70 years of age with CAT should undergo a systematic frailty evaluation before choosing treatment and modifiable bleeding risk factors should be addressed. In patients with renal impairment, creatine clearance should be assessed and monitored regularly thereafter. In patients with an eGFR less than 30mL/min/1.72m2, the anticoagulant treatment may need to be adapted. Similarly, platelet count should be assessed prior to treatment and monitored regularly. In patients with grade 3-4, thrombocytopenia (less than 50,000platelets/μL) treatment with a LMWH at a reduced dose should be considered. For patients with CAT and low body weight, standard anticoagulant treatment recommendations are appropriate, whereas in obese patients, apixaban may be preferred.

Evaluation of acute thrombus regression effect of edoxaban for deep vein thrombosis in patients with cancer: a single-center prospective observational study

BACKGROUND

Although there are reports on the recurrence prevention in the chronic phase using direct oral anticoagulants (DOACs) for deep vein thrombosis (DVT) in patients with cancer, acute thrombus regression effect using DOACs has not been assessed. This study aimed to assess the thrombus regression effect of initial treatment using edoxaban for acute lower-extremity DVT in patients with active cancer.

METHODS AND RESULTS

In this observational study, among the inpatients with cancer and lower-extremity DVT who underwent initial treatment with edoxaban at our hospital from November 2019 to December 2021, 34 consenting patients were recruited in this study. The quantitative ultrasound thrombus (QUT) score of thrombus volume was calculated at baseline (before administration) and 7-14 days after the start of edoxaban administration, using lower-extremity venous ultrasound to evaluate changes in thrombus volume. The primary and secondary endpoints were the acute thrombus regression effect of edoxaban and the impact of patients' clinical frailty on the thrombus regression effect, respectively. Anticoagulant therapy with edoxaban significantly reduced QUT score (p < 0.001). In addition, regardless of the Clinical Frailty Scale scores, QUT score decreased significantly.

CONCLUSION

Initial treatment with edoxaban was effective for lower-extremity DVT in patients with cancer. In addition, the effect was the same independent of the degree of frailty.

Management of cancer-associated thromboembolism in vulnerable population

Although all patients with cancer-associated thrombosis (CAT) have a high morbidity and mortality risk, certain groups of patients are particularly vulnerable. This may expose the patient to an increased risk of thrombotic recurrence or bleeding (or both), as the benefit-risk ratio of anticoagulant treatment may be modified. Treatment thus needs to be chosen with care. Such vulnerable groups include older patients, patients with renal impairment or thrombocytopenia, and underweight and obese patients. However, these patient groups are poorly represented in clinical trials, limiting the available data, on which treatment decisions can be based. Meta-analysis of data from randomised clinical trials suggests that the relative treatment effect of direct oral factor Xa inhibitors (DXIs) and low molecular weight heparin (LMWH) with respect to major bleeding could be affected by advanced age. No evidence was obtained for a change in the relative risk-benefit profile of DXIs compared to LMWH in patients with renal impairment or of low body weight. The available, albeit limited, data do not support restricting the use of DXIs in patients with CAT on the basis of renal impairment or low body weight. In older patients, age is not itself a critical factor for choice of treatment, but frailty is such a factor. Patients over 70 years of age with CAT should undergo a systematic frailty evaluation before choosing treatment and modifiable bleeding risk factors should be addressed. In patients with renal impairment, creatine clearance should be assessed and monitored regularly thereafter. In patients with an eGFR<30mL/min/1.72m2, the anticoagulant treatment may need to be adapted. Similarly, platelet count should be assessed prior to treatment and monitored regularly. In patients with grade 3-4, thrombocytopenia (<50,000 platelets/μL) treatment with a LMWH at a reduced dose should be considered. For patients with CAT and low body weight, standard anticoagulant treatment recommendations are appropriate, whereas in obese patients, apixaban may be preferred.

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.

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.

The Role of Injectables in the Treatment and Prevention of Cancer-Associated Thrombosis

Cancer-associated thrombosis (CAT) is a leading cause of death among patients with cancer. CAT can manifest itself as venous thromboembolism (VTE), in the form of deep vein thrombosis or pulmonary embolism, or arterial thromboembolism. The pathophysiology of CAT is complex and depends on cancer-, patient-, treatment- and biomarkers-related factors. Treatment of VTE in patients with cancer is complex and includes three major classes of anticoagulant agents: heparin and its derivatives, e.g., low molecular weight heparins, direct oral anticoagulants (DOACs), and vitamin K inhibitors. Given the tremendous heterogeneity of clinical situations in patients with cancer and the challenges of CAT, there is no single universal treatment option for patients suffering from or at risk of CAT. Initial studies suggested that patients seemed to prefer an anticoagulant that would not interfere with their cancer treatment, suggesting the primacy of cancer over VTE, and favoring efficacy and safety over convenience of route of administration. Recent studies show that when the efficacy and safety aspects are similar, patients prefer the oral route of administration. Despite this, injectables are a valid option for many patients with cancer.

Primary prevention of cancer-associated venous thrombosis: Rationale and challenges in clinical practice

Cancer-associated venous thrombosis (CAT) is a common, multifactor event known to complicate the course of cancer and jeopardize a patient's prognosis. The current guidelines regarding the prevention of CAT are sometimes considered insufficiently precise about specific situations, or are poorly applied. The expected benefits of thromboprophylaxis are balanced by the risk of major bleeding induced by anticoagulation, which implies a need to accurately identify ambulatory patients at high risk of thrombosis or hemorrhage. The Khorana score is commonly used for this, but is limited by the non-reproducibility of predicted performance across cancer types, and by the fact that antitumor treatment and cardiovascular risks are not included. The COMPASS-CAT score, which includes those two aspects, was found to be a more accurate predictor of venous thromboembolism in patients with lung cancer, and to better distinguish between patients at low or high risk of thrombosis. The frailty of patients with cancer is also a major issue, and should be taken into account when thromboprophylaxis is considered. According to current guidelines, CAT prophylaxis should be considered for hospitalized patients, those for whom surgery is scheduled, or those with pancreatic cancers. In ambulatory patients, decisions should be made according to patient, cancer and antitumoral treatment characteristics. Low molecular weight heparin is the gold standard of CAT prophylaxis. Despite increased risks of bleeding or drug-drug interactions in cancer patients, direct oral anticoagulants could be alternate options for high-risk ambulatory patients that should be accompanied by a careful global analysis of benefits, harms, and patient preferences.

[Prophylaxis and management of cancer-associated thrombosis: Practical issues about anticoagulant use]

Cancer-associated thrombosis (CAT) is a common complication resulting from various vascular mechanisms related to cancer, antitumoral therapy and patient status, and is associated with a poor prognosis. Anticoagulants recommended for CAT treatment or prevention mainly include low molecular weight heparin (LMWH) and direct oral anticoagulants (DOACs). Regarding thromboprophylaxis, a situation for which LMWH is a preferred option due to a lower risk of hemorrhage especially in patients with unresected gastro-intestinal and genito-urinary malignancies, the identification of patients at risk is a major issue. For patients with established CAT, the main issue is the choice of the most appropriate anticoagulant therapy. Because of the convenience of oral formulation, DOACs are an attractive option, and their efficacy has been shown in randomized trials. However, such studies are limited by selection biases, which make the analyzed population not representative of the real-life setting, as for instance cancers associated with a high risk of hemorrhage, or antitumoral therapies (e.g., tyrosine kinase inhibitors) known to interact with DOACs and then modifying their bioavailability. Caution associated with DOAC use is highlighted by most updated guidelines that recommend a case-by-case-based approach. The aim of the present paper is to help the oncologists make the most appropriate decision regarding the choice of anticoagulant therapy in a context of thromboprophylaxis or established CAT management in a patient with a solid tumor. The main issues are addressed through key practical questions, the answers of which are based on the current guidelines and additional published data or expert opinions.

Inpatient primary prophylaxis of cancer-associated thromboembolism (CAT)

PURPOSE

Cancer-associated thrombosis (CAT) increases morbidity and mortality in oncology patients. The risk of CAT is increased with hospitalization for acute medical illness. The goal of this review will be to examine the available evidence for (1) risk assessment and (2) primary thromboprophylaxis, (3) international published guideline recommendations, and (4) future directions to manage oncology patients admitted for an acute medical illness.

METHODS

A review was performed for each subject to gather information on the available evidence and recommendations available for oncology patients hospitalized for an acute medical illness.

RESULTS

Risk assessments for thrombosis are primarily developed and validated in the general population. There is not a risk assessment that has specifically been developed and validated in oncology patients hospitalized for an acute medical illness. Most evidence for thromboprophylaxis of oncology patients is from sub-group analysis of larger randomized-controlled trials in the general population. Evidence is conflicting and suggests an individualized approach evaluating the risk-benefit of thromboprophylaxis. The strength of recommendations of international guidelines is limited because of the available evidence. Guidelines usually recommend utilizing and/or offering thromboprophylaxis to oncology patients hospitalized for an acute medical illness barring contraindications. Future evidence needs to improve risk assessments and knowledge of the appropriate agent, dose, and duration of thromboprophylaxis if indicated.

CONCLUSION

Evidence for risk assessments and primary prophylaxis for oncology patients hospitalized for acute medical illness appears limited, with many research opportunities available to improve understanding on management of this patient population.

Risk Factors, Incidence, and Prognosis of Thromboembolism in Cancer Patients Treated With Immune Checkpoint Inhibitors

In recent years, immune checkpoint inhibitors (ICIs) have become the standard treatment option for tumors. With the widespread application of ICIs, immune-related adverse events (irAEs) have gradually attracted the attention of researchers. Owing to the characteristics of ICIs, irAEs can affect each organ of the human body. Thromboembolism is uncommon in cancer patients receiving ICIs, but it may affect their survival. Most thromboembolic events do not cause serious effects after early prediction and treatment, but life-threatening toxic reactions are also observed. This condition should not be ignored because of vague and atypical symptoms, which make early diagnosis more challenging. This article focuses on the high-risk factors, underlying mechanisms, incidence, and prognosis of thromboembolism in patients using ICIs and briefly describes the intervention and treatment measures. This information would allow patients to effectively manage the side effects of thromboembolism during Immune checkpoint inhibitors treatment, ensuring the efficacy of ICIs and reducing mortality.

Poorer baseline performance status is associated with increased thromboembolism risk in metastatic cancer patients treated with immunotherapy

PURPOSE

Venous thromboembolism (VTE) is a significant cause of morbidity and mortality in cancer patients. However, the association of VTE with immunotherapy remains poorly defined. We therefore evaluated the frequency of VTE in patients receiving immunotherapy and tried to determine predisposing factors.

METHODS

A total of 133 adult metastatic cancer patients treated with immunotherapy for any cancer between were included. Baseline demographics, ECOG performance status, type of tumors, and baseline blood count parameters were recorded. Possible predisposing factors were evaluated with univariate and multivariate analyses.

RESULTS

The median age was 60 (interquartile range (IQR) 48-66) years, and the median follow-up was 10.1 (IQR 5.8-18.5) months. Renal cell carcinoma (26.3%) and melanoma (24.1%) were most common diagnoses. Fifteen patients (11.3%) had an episode of VTE. Most of the VTEs were diagnosed as pulmonary emboli (10/15; 67%). Eighty percent (12/15) of these VTE cases were detected incidentally. Patients with a baseline ECOG performance status of 1 or more (29.3% of patients) had a significantly increased risk of venous thrombosis (ECOG ≥1 vs. 0, HR: 3.023, 95% CI: 1.011-9.039, p=0.048). Other factors, including patient age, tumor type, body mass index, baseline thrombocyte, neutrophil, and lactate dehydrogenase levels were not significantly associated with VTE risk.

CONCLUSIONS

In this study, we observed VTE development in more than 10% of immunotherapy-treated patients and increased VTE risk in patients with poorer ECOG status. With the asymptomatic nature of VTEs in most cases, a high index of suspicion level for VTE is required in patients treated with immunotherapy.

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

Background: extended anticoagulant therapy beyond the initial 6 months is suggested in patients with cancer-associated thrombosis (CAT) and active cancer. Few data are available on patient management and outcomes on the period between 6 and 12 months after the venous thromboembolism (VTE) event. Objectives: our objective was to document patient management and outcomes beyond 6 months and up to 12 months in CAT patients initially treated for 6 months with tinzaparin. Methods: adult CAT patients with a cancer still alive at the end of an initial 6-month treatment period were eligible to participate in this retrospective non-interventional French multicenter study. Results: a total of 432 patients aged 66.5 ± 12.7 years were available to participate in this study. Out of the patients included in the study, the anticoagulant treatment was maintained in 348 of 422 documented patients (82.5%) while it was discontinued in 74 (17.5%) patients (before the end or at the end of the initial 6-month treatment period). Between 6 and 12 months, 24 patients (5.7%) experienced VTE recurrence, while 21 (5.1%) patients had clinically relevant bleeding, 11 patients (2.7%) had major bleeding and 96 patients (22.3%) died, mostly from cancer. VTE recurrence was more frequent in patients with lung (14.3%) and colorectal cancer (6.0%) while major bleeding was more frequent in patients with colorectal cancer (6.0%). Conclusion: clinical outcomes were consistent with previous observations and variable according to the type of cancer. Further clinical research is required to orient the management of patients with CAT beyond 6 months based on cancer-specific treatment strategies.

Platelet-T cell aggregates in lung cancer patients: Implications for thrombosis

Platelet-leukocyte aggregates (PLAs) are associated with increased thrombosis risk. The influence of PLA formation is especially important for cancer patients, since thrombosis accounts for approximately 10% of cancer-associated deaths. Our objective was to characterize and quantify PLAs in whole blood samples from lung cancer patients compared to healthy volunteers with the intent to analyze PLA formation in the context of lung cancer-associated thrombosis. Consenting lung cancer patients (57) and healthy volunteers (56) were enrolled at the Dana Cancer Center at the University of Toledo Health Science Campus. Peripheral blood samples were analyzed by flow cytometry. Patient medical history was reviewed through electronic medical records. Most importantly, we found lung cancer patients to have higher percentages of platelet-T cell aggregates (PTCAs) than healthy volunteers among both CD4+ T lymphocyte and CD8+ T lymphocyte populations. Our findings demonstrate that characterization of PTCAs may have clinical utility in differentiating lung cancer patients from healthy volunteers and stratifying lung cancer patients by history of thrombosis.

Treatment of venous thromboembolism with tinzaparin in oncological patients

Venous thromboembolism (VTE) is a major cause of morbidity and mortality in patients with cancer. For over a decade, the gold standard of treatment and secondary prevention of cancer-associated thrombosis (CAT) has been represented by low-molecular-weight heparins (LMWHs), which are currently recommended as the first-line treatment for CAT. Among the LMWHs that were more extensively tested in patients with CAT, tinzaparin is a LMWH produced by the enzymatic degradation of porcine-derived unfractionated heparin. The efficacy of tinzaparin in this setting is supported by well-grounded evidence. However, there is a need to discuss the positioning of tinzaparin in the continuously evolving treatment scenario of VTE therapy in cancer patients. In this paper, which was developed by a group of clinicians with wide experience in the treatment of VTE in cancer patients, we discuss the current therapeutic options and the role of tinzaparin for the treatment of CAT.