Prevention of venous thromboembolism in cancer patients: current approaches and opportunities for improvement

Venous thromboembolism (VTE), a common complication in patients with cancer, is associated with increased risk of morbidity, mortality, and recurrent VTE. Risk factors for VTE in cancer patients include the type and stage of cancer, comorbidities, age, major surgery, and active chemotherapy. Evidence-based guidelines for thromboprophylaxis in cancer patients have been published: the National Comprehensive Cancer Network and American Society for Clinical Oncology guidelines recommend thromboprophylaxis for hospitalized cancer patients, while the American College of Chest Physician guidelines recommend thromboprophylaxis for surgical patients with cancer and bedridden cancer patients with an acute medical illness. Guidelines do not generally recommend routine thromboprophylaxis in ambulatory patients during chemotherapy, but there is evidence that some of these patients are at risk of VTE; some may be at higher risk while on active chemotherapy. Approaches are needed to identify those patients most likely to benefit from thromboprophylaxis, and, to this end, a risk assessment model has been developed and validated. Despite the benefits, many at-risk patients do not receive any thromboprophylaxis, or receive prophylaxis that is not compliant with guideline recommendations. Quality improvement initiatives have been developed by the Centers for Medicare and Medicaid Services, National Quality Forum, and Joint Commission to encourage closure of the gap between guideline recommendations and clinical practice for prevention, diagnosis, and treatment of VTE in hospitalized patients. Health-care institutions and providers need to take seriously the burden of VTE, improve prophylaxis rates in patients with cancer, and address the need for prophylaxis across the patient continuum.     

Prediction and Prevention of Cancer‐Associated Thromboembolism

Venous and arterial thromboembolism are prevalent, highly burdensome, and associated with risk of worse outcomes for patients with cancer. Risk for venous thromboembolism (VTE) varies widely across specific cancer subpopulations. The ability to predict risk of cancer‐associated VTE is critical because an optimal thromboprophylaxis strategy is best achieved by targeting high‐risk patients with cancer and avoiding prophylaxis in patients with cancer at low risk for VTE. A validated risk tool for solid tumors has been available for a decade. Newer tools have focused on specific populations, such as patients with multiple myeloma. Emerging studies continue to optimize risk prediction approaches in patients with cancer. Recent randomized trials have specifically addressed risk‐adapted thromboprophylaxis using direct oral anticoagulants, and revised guidelines have included these new data to formulate recommendations for outpatient thromboprophylaxis. Implementation science approaches to enhance use of outpatient prophylaxis in the context of these guideline changes are under way. However, major knowledge gaps remain, including a lack of data for inpatient thromboprophylaxis in the cancer setting and a lack of formal tools for identifying risk of bleeding. This review describes optimal approaches to risk prediction and patient selection for primary pharmacologic thromboprophylaxis of cancer‐associated VTE, addresses barriers to implementing these practices, and highlights strategies to overcome them.Implications for PracticeRisk for venous thromboembolism (VTE) varies widely among patients with cancer. Individual risk can be determined using validated approaches. Inpatient and postsurgical thromboprophylaxis is more widely accepted. However, most patients with cancer develop VTE in the outpatient setting. Recent randomized trials have demonstrated benefit to risk‐adapted outpatient thromboprophylaxis. High‐risk patients may therefore be considered for outpatient thromboprophylaxis as recommended by recently updated guidelines. System‐wide implementation approaches are necessary to improve compliance with prophylaxis.     

Primary Thromboprophylaxis and the Risk of Venous Thromboembolic Events in Patients With Testicular Germ Cell Tumors Treated With Cisplatinum-Based Chemotherapy

BackgroundCisplatinum-based chemotherapy is associated with an increased risk of venous thromboembolism (VTE). We hypothesized that primary thromboprophylaxis in patients with testicular germ cell tumors (GCT) undergoing cisplatinum-based chemotherapy can reduce the risk of VTE.Patients and MethodsIn this single-center retrospective cohort study, we investigated the increased use of primary thromboprophylaxis between January 2000 and December 2021 at our institution and its effect on the risk of VTE. Patients with GCT undergoing adjuvant or curative cisplatinum-based chemotherapy were included.ResultsThree hundred forty-six patients with GCT initiating a cisplatinum-based therapy were included in the study, of whom 122 (35%) were treated in the adjuvant and 224 (65%) in the curative setting, respectively. VTE events occurred in 49 (14.2%) patients. In univariable competing risk analysis, a higher clinical tumor stage and large retroperitoneal lymphadenopathy (RPLND >5 cm) were the strongest predictors of an elevated VTE risk (SHR for stage IIC - IIIC: 2.6 (95%CI: 5.0-24.7, P < .001), SHR for RPLN: 2.36 (95%CI: 1.27-4.4, P < .007)). The proportion of patients receiving primary thromboprophylaxis strongly increased over time and reached 100% in CS IIC-III patients from 2019 onwards. After adjusting for tumor stage, primary thromboprophylaxis was associated with a 52% relatively lower risk of VTE (SHR = 0.48, 95% CI: 0.24-0.97; P = .032).ConclusionIn this retrospective cohort study, we showed that TGCT patients undergoing cisplatinum-based chemotherapy have a lower VTE risk when receiving primary thromboprophylaxis. For the duration of chemotherapy, primary thromboprophylaxis should be considered on a risk-benefit ratio.     

肿瘤患者静脉血栓栓塞抗凝出血与复发风险研究进展

肿瘤相关静脉血栓栓塞症(cancer-associated venous thromboembolism, CAVTE)为肿瘤患者在疾病进程中的常见并发症和死亡原因。其静脉血栓栓塞症(venous thromboembolism, VTE)复发和抗凝后严重出血的高风险可能会导致治疗延误和死亡率增加。目前, 国内外指南并未推荐对所有门诊患者直接进行一级预防, 但建议在化疗前评估发生静脉血栓栓塞的个体风险。本文对目前肿瘤患者静脉血栓栓塞抗凝出血与复发研究进展以及现行VTE防治指南和VTE风险评估模型进行综述。      

Safety and efficacy of primary thromboprophylaxis in cancer patients

Cancer is often complicated by venous thromboembolism (VTE), a common and potentially fatal complication associated with poor prognosis in these patients. An increased incidence of VTE is being observed due to the advanced age of cancer patients, the thrombogenic effect of novel drugs and advances in the diagnosis of related complications. In this review, we look at five different risk groups of cancer patients with an increased probability of developing VTE, including hospitalized patients undergoing chemotherapy, patients undergoing a surgical procedure, ambulatory patients undergoing chemotherapy, patients with a central venous access and patients receiving antiangiogenic drugs or anticoagulant therapy due to previous chronic diseases. The aim of this review is to summarize the most important clinical evidence reported to date on the suitability of primary thromboprophylaxis to cancer patients. Recommendations have drawn up for each group based on current evidence and guidelines to facilitate decision-making in clinical practice.     

Risk assessment and prophylaxis for VTE in cancer patients

The frequency of venous thromboembolism (VTE) is rising in patients with cancer. VTE contributes to mortality and morbidity, but the risk for VTE can vary widely between individual patients. Clinical risk factors for VTE in cancer include primary site of cancer, use of systemic therapy, surgery, and hospitalization. Biomarkers predictive of VTE include platelet and leukocyte counts, hemoglobin, D-dimer, and tissue factor. A recently validated risk model incorporates 5 easily available variables and can be used clinically to identify patients at increased risk of VTE. In high-risk settings, including surgery and hospitalization, thromboprophylaxis with either unfractionated heparin or low-molecular-weight heparins has been shown to be safe and effective. Recent studies have also suggested a potential benefit for thromboprophylaxis in the ambulatory setting, although criteria for selecting patients for prophylaxis are not currently well defined. This article focuses on recent and ongoing studies of risk assessment and prophylaxis in patients with cancer.     

Lack of prophylaxis before the onset of acute venous thromboembolism among hospitalized cancer patients: the SWIss Venous ThromboEmbolism Registry (SWIVTER)

Background: Venous thromboembolism (VTE) prophylaxis remains underutilized, particularly in cancer patients. We explored clinical predictors of prophylaxis in hospitalized cancer patients before the onset of acute VTE.Methods: In the SWiss Venous ThromboEmbolism Registry, 257 cancer patients (61 ± 15 years) with acute VTE and prior hospitalization for acute medical illness or surgery within 30 days (91% were at high risk with Geneva VTE risk score ≥3) were enrolled.Results: Overall, 153 (60%) patients received prophylaxis (49% pharmacological and 21% mechanical) before the onset of acute VTE. Outpatient status at the time of VTE diagnosis [odds ratio (OR) 0.31, 95% confidence interval (CI) 0.18–0.53], ongoing chemotherapy (OR 0.51, 95% CI 0.31–0.85), and recent chemotherapy (OR 0.53, 95% CI 0.32–0.88) were univariately associated with the absence of VTE prophylaxis. In multivariate analysis, intensive care unit admission within 30 days (OR 7.02, 95% CI 2.38–20.64), prior deep vein thrombosis (OR 3.48, 95% CI 2.14–5.64), surgery within 30 days (OR 2.43, 95% CI 1.19–4.99), bed rest >3 days (OR 2.02, 95% CI 1.08–3.78), and outpatient status (OR 0.38, 95% CI 0.19–0.76) remained the only independent predictors of thromboprophylaxis.Conclusions: Although most hospitalized cancer patients were at high risk, 40% did not receive any prophylaxis before the onset of acute VTE. There is a need to improve thromboprophylaxis in cancer patients, particularly in the presence of recent or ongoing chemotherapy.     

Prevention and management of venous thromboembolism in people with cancer: a review of the evidence

Venous thromboembolism (VTE) constitutes an important health problem in developed countries. Owing to their underlying malignancies, people with cancer are at particularly high risk of VTE. The level of this risk is influenced by several factors, including type of cancer and the presence or absence of metastases. However, different types of oncology treatment can also further increase the thrombotic risk. Consequently, primary and secondary thromboprophylaxis in people with cancer should be considered as part of any integrated oncology treatment. Moreover, recent exciting studies have suggested that low molecular weight heparins (LMWH) may also influence overall survival in people with cancer. Clearly, these findings raise the likelihood that the use of LMWH in oncology practice may increase significantly in the near future. However, it is important to appreciate that the use of thromboprophylaxis in people with cancer is complicated by a number of specific problems. In this overview, we have systematically addressed the difficult clinical issues that are involved in the selection of appropriate primary and secondary thromboprophylaxis for people with cancer.     

宫颈癌患者合并静脉血栓栓塞症的危险因素和治疗

目的:探讨宫颈癌化疗患者合并静脉血栓栓塞症的危险因素与治疗.方法:回顾性分析2010年至2015年我院158例宫颈癌化疗患者,按是否合并静脉血栓栓塞症(VTE)分成VTE组(n=40)与无VTE组(n=118),记录分析两组的性别、年龄、既往史、病例类型、肿瘤分期、血小板计数、血黏稠度、D-二聚体以及治疗措施.结果:VET组Ⅳ期:90.00%,血黏稠度增高:67.50%,D-二聚体增高:70.00%;无VTE组Ⅳ期:70.34%,血黏稠度增高:46.61%,D-二聚体增高:49.15%(均P<0.05).Logistic回归显示:肿瘤分期、D-二聚体水平以及血黏稠度与宫颈癌化疗患者发生静脉血栓高度相关,差异均有统计学意义(均P<0.05).40例宫颈癌化疗合并VTE患者2例并发大出血死亡;其余经溶栓、抗凝治疗后19例治愈,4例好转,总有效率为57.50%.结论:宫颈癌肿瘤分期晚、D-二聚体水平高以及血黏稠度高与宫颈癌化疗患者发生静脉血栓高度相关,为宫颈癌患者并发VTE的高危因素;及时评价宫颈癌化疗患者合并VTE的高危因素,及早抗凝治疗,可预防及减少并发VTE,同时提高治疗效果.     

Cancer and thrombosis: implications of published guidelines for clinical practice

Cancer is a frequent finding in patients with thrombosis, and thrombosis is much more prevalent in patients with cancer, with important clinical consequences. Thrombosis is the second most common cause of death in cancer patients. Venous thromboembolism (VTE) in cancer is also associated with a high rate of recurrence, bleeding, a requirement for long-term anticoagulation, and worsened quality of life. Risk factors for cancer-associated VTE include particular cancer types, chemotherapy (with or without antiangiogenic agents), the use of erythropoietin-stimulating agents, the presence of central venous catheters, and surgery. Novel risk factors include platelet and leukocyte counts and tissue factor. A risk model for identifying cancer patients at highest risk for VTE has recently been developed. Anticoagulant therapy is safe and efficacious for prophylaxis and treatment of VTE in patients with cancer. Available anticoagulants include warfarin, heparin, and low-molecular weight heparins (LMWHs). LMWHs represent the preferred therapeutic option for VTE prophylaxis and treatment. Their use may be associated with improved survival in cancer, although this issue requires further study. Despite the significant burden imposed by VTE and the availability of effective anticoagulant therapies, many oncology patients do not receive appropriate VTE prophylaxis as recommended by practice guidelines. Improved adherence to guidelines could substantially reduce morbidity, decrease resource use, enhance quality of life, and improve survival in these patients.     

Risk factors for chemotherapy-associated venous thromboembolism in a prospective observational study

BACKGROUND: The incidence of venous thromboembolism (VTE) is increased in cancer, but little information is available about risk factors in cancer patients on chemotherapy. METHODS: We analyzed data from a prospective, multicenter observational study to determine the frequency and risk factors for VTE in ambulatory cancer patients initiating a new chemotherapy regimen. The association of VTE with clinical variables was characterized using univariate and multivariate analysis. RESULTS: Among 3003 patients treated with at least one cycle of chemotherapy, VTE occurred in 58 (1.93%) over a median follow-up of 2.4 months (0.8%/mo). The incidence varied significantly by site of cancer (P = 0.01) with highest rates in upper gastrointestinal (2.3%/mo) and lung cancer (1.2%/mo), and lymphoma (1.1%/mo). An elevated prechemotherapy platelet count was significantly associated with an increased rate of VTE (P for trend = 0.005). The incidence of VTE was 3.98% (1.66%/mo) for patients with a prechemotherapy platelet count > or = 350,000, compared with 1.25% (0.52%/mo) for patients with platelet counts of < 200,000 (P for trend=0.0003). In multivariate analysis, a prechemotherapy platelet count of > or = 350,000/mm(3) (adjusted OR 2.81, 95% CI 1.63-4.93, P = 0.0002), site of cancer, hemoglobin < 10 g/dL or use of erythropoietin, and use of white cell growth factors in high-risk sites of cancer were significantly associated with VTE. CONCLUSIONS: Symptomatic VTE is a frequent complication of chemotherapy. The prechemotherapy platelet count is a unique risk factor and can help identify high-risk patients for future trials of thromboprophylaxis.     

Thromboembolische Komplikationen – Prophylaxe und Therapie im Fokus

Cancer patients are at increased risk of thromboembolic complications, which are commonly referred to as Trousseau’s syndrome. Besides the potentially dramatic effects of the tumor on the coagulation and fibrinolytic systems, various supportive measures and more specific cancer treatments, such as surgery or chemotherapy contribute to the pathophysiology of cancer-associated venous thromboembolism (VTE). Clinical trials have shown that long-term therapy with low-molecular-weight heparin (LMWH) is superior to secondary prophylaxis with vitamin K antagonists in the treatment of patients with cancer-associated VTE. Based on currently available clinical evidence it is not clear which cancer patient should be offered primary thromboprophylaxis with LMWH. In this respect, the individual risk profile which is substantially influenced by the general condition of the patient and possible co-morbidities have to be taken into account. Recent experimental and clinical studies have suggested that LMWH affects tumor biology at various levels and may thus be potentially beneficial as an adjunct in cancer therapy.     

Frequency, risk factors, and trends for venous thromboembolism among hospitalized cancer patients

BACKGROUND: Venous thromboembolism (VTE) contributes to morbidity and mortality in cancer patients and is a frequent complication of anticancer therapy. In the current study, the frequency, risk factors, and trends associated with VTE were examined among hospitalized cancer patients. METHODS: A retrospective cohort study was conducted using the discharge database of the University HealthSystem Consortium. This included 1,824,316 hospitalizations between 1995 and 2003 at 133 U.S. medical centers. RESULTS: Among 1,015,598 cancer patients, 34,357 (3.4%) were diagnosed with deep venous thrombosis and 11,515 with pulmonary embolism (PE) (1.1%) for an overall VTE rate of 4.1%. Subgroups of cancer patients with the highest rates included black ethnicity (5.1% per hospitalization) and those receiving chemotherapy (4.9%). Sites of cancer with the highest rates of VTE included pancreas (8.1%), kidney (5.6%), ovary (5.6%), lung (5.1%), and stomach (4.9%). Among hematologic malignancies, myeloma (5%), non-Hodgkin lymphoma (4.8%), and Hodgkin disease (4.6%) had the highest rates of VTE. The rate of VTE increased by 28%, secondary to a near-doubling of PE rates from 0.8% to 1.5% (P < .0001). Among patients receiving chemotherapy, the rates of VTE rose from 3.9% to 5.7%, an increase of 47% (P < .0001). In multivariate analysis, risk factors associated with VTE included age >or=65 years, female sex, black ethnicity, use of chemotherapy, primary site of cancer, presence of comorbidities, and year of admission. CONCLUSIONS: VTE, particularly PE, is an increasingly frequent complication of hospitalization in cancer patients. Patients with black ethnicity, specific sites of cancer, or those receiving chemotherapy are disproportionately at risk.     

Risk of venous thromboembolism in patients undergoing cancer surgery and options for thromboprophylaxis

Patients with cancer have an increased risk of developing venous thromboembolism (VTE) due to a hypercoagulable state associated with malignancy. This risk is further complicated in patients undergoing cancer-related surgery due to immobility, other cancer treatments, and biologic changes associated with surgery. Despite this relatively high risk of VTE, many patients are not prescribed adequate prophylaxis in the pre- or post-operative periods. This article reviews available measures for thromboprophylaxis in light of current guidelines.     

A Predictive Score for Thrombosis Associated with Breast,Colorectal, Lung,or Ovarian Cancer: The Prospective COMPASS–Cancer‐Associated Thrombosis Study

Background

The stratification of outpatients on chemotherapy for breast, colorectal, lung, and ovarian cancers at risk of venous thromboembolism (VTE) remains an unmet clinical need. The derivation of a risk assessment model (RAM) for VTE in these patients was the aim of the study “Prospective Comparison of Methods for thromboembolic risk assessment with clinical Perceptions and AwareneSS in real life patients–Cancer Associated Thrombosis” (COMPASS–CAT).

Patients and Methods

The derivation cohort consisted of 1,023 outpatients. Patients on low molecular weight heparin (LMWH) thromboprophylaxis were excluded. Documented symptomatic VTE was the endpoint of the study.

Results

Patients had breast (61%), colorectal (17%), lung (13%), or ovarian cancer (8.6%) at localized (30%) or advanced stage (70%). In 64% of patients, cancer was diagnosed within the last 6 months prior to inclusion. Most of them were on chemotherapy when assessed. Symptomatic VTE occurred in 8.5% of patients. The COMPASS–CAT RAM includes the following variables: (a) anthracycline or anti‐hormonal therapy, (b) time since cancer diagnosis, (c) central venous catheter, (d) stage of cancer, (e) presence of cardiovascular risk factors, (f) recent hospitalization for acute medical illness, (g) personal history of VTE, and (h) platelet count. At 6 months, patients stratified at low/intermediate and high‐risk groups had VTE rates of 1.7% and 13.3%, respectively. The area under the curve of receiver operating characteristics analysis was 0.85. The sensitivity and specificity of the RAM were 88% and 52%, respectively. The negative and positive predictive values of the RAM were 98% and 13%, respectively.

Conclusion

The COMPASS–CAT RAM includes reliable and easily collected VTE risk predictors and, in contrast to the Khorana score, it is applicable after the initiation of anticancer treatment in patients with common solid tumors. Its robustness for stratification of patients at high and low/intermediate VTE risk needs to be externally validated.

Implications for Practice

The Prospective Comparison of Methods for thromboembolic risk assessment with clinical Perceptions and AwareneSS in real life patients–Cancer Associated Thrombosis (COMPASS–CAT) study provides a new risk assessment model (RAM) for venous thromboembolism (VTE) applicable in outpatients with breast, colorectal, lung or ovarian cancer. The COMPASS–CAT RAM is robust, applicable during chemotherapy and determines the need for VTE prévention by including reliable and easily collected VTE predictors associated with cancer status, its treatment as well as with patients' characteristics and comorbidities. An independent external validation of the RAM is indicated before its use in clinical practice.     

Primary thromboprophylaxis for cancer patients with central venous catheters--a reappraisal of the evidence

Venous thromboembolism (VTE) is responsible for an estimated 25 000 deaths per annum in UK hospital practice. It is well established that many of these deaths could be prevented through the use of appropriate thromboprophylaxis. This issue is of particular relevance in oncology practice, where the risks of VTE and bleeding are both significantly higher than those observed in general medical patients. Cancer patients with in-dwelling central venous catheters (CVCs) are at particularly high risk of developing thrombotic complications. However, the literature has produced conflicting conclusions regarding the efficacy of using routine primary thromboprophylaxis in these patients. Indeed such is the level of confusion around this topic, that the most recent version of the American College of Chest Physicians (ACCP) guidelines published in 2004 actually reversed their previous recommendation (published in 2001). Nevertheless, minidose warfarin continues to be routinely used in many oncology centres in the UK. In this article, we have performed a systematic review of the published literature regarding the efficacy and the risks, associated with using thromboprophylaxis (either minidose warfarin or low-dose LMWH) in cancer patients with CVC. On the basis of this evidence, we conclude that there is no proven role for using such thromboprophylaxis. However, asymptomatic CVC-related venous thrombosis remains common, and further more highly powered studies of better design are needed in order to define whether specific subgroups of cancer patients might benefit from receiving thromboprophylaxis.     

Thrombosis and cancer

Venous thromboembolism (VTE) is a potentially life-threatening condition that can be associated with significant morbidity. Thrombosis and cancer are linked by numerous pathophysiological mechanisms; the frequency of VTE and the recurrence rate are increased in the cancer population in comparison with other patient groups. VTE is the second most common cause of death in patients with cancer, but can also be the initial presenting complaint in patients with an occult malignancy. Risk factors for cancer-related VTE include tumour type, surgery, chemotherapy and the use of central venous catheters; predictors of VTE for individuals are only now beginning to emerge. Patients with cancer who develop symptomatic VTE during chemotherapy are at a greater risk of early mortality than those without VTE. The apparent impact of VTE on early mortality in patients with cancer raises the question of whether anticoagulation might improve long-term survival in this population, by direct tumour biology-modifying mechanisms. There are widely published guidelines that highlight the benefits of effective VTE strategies in patients with cancer. In partnership with the patient and their carers, the clinical team can improve patient outcomes with optimal risk assessment and concordance with national and international guidelines in the prophylaxis and treatment of VTE.     

Thromboprophylaxis in major abdominal surgery for cancer.

AIMS: To review the epidemiology and pathogenesis of venous thromboembolism (VTE) in surgical cancer patients, in addition to the use of thromboprophylaxis in major abdominal surgery, such as low-molecular-weight heparin (LMWH) and fondaparinux. METHODS: Systematic review of the literature, focussing on risk factors for VTE, parenteral methods of thromboprophylaxis, approaches to prolonged prophylaxis, and effects on patient survival. FINDINGS: Patients with cancer undergoing abdominal surgery are at substantially higher risk for VTE than patients without cancer. Furthermore, prolonged thromboprophylaxis for up to 4 weeks is more effective than short-term administration in these high-risk patients. The concurrent use of graduated compression stockings has a synergistic effect on the reduction in VTE risk. CONCLUSIONS: Thromboprophylaxis with LMWH has been shown to minimise the incidence of thromboembolic events, and is a well-established therapy worldwide. The American College of Chest Physicians recommends the routine use of thromboprophylaxis, with LMWH or unfractionated heparin, in patients with cancer who are undergoing surgical procedures, and the appropriate use of these thromboprophylactic agents has significant implications for the clinical care and quality of life of surgical patients with cancer.     

Preventing thromboembolic complications in cancer patients after surgery: a role for prolonged thromboprophylaxis

Patients undergoing major abdominal surgery for malignancy are at particularly high risk of developing VTE. Extra protection against this can be given to patients with cancer by using a higher dose of LMWH than normally used for prophylaxis, with no increase in bleeding complications. Despite thromboprophylaxis with high-dose LMWH for the first postoperative week, the rate of late VTE is estimated to be between 10% and 20%. A meta-analysis of two studies using dalteparin or enoxaparin has shown that prolonging thromboprophylaxis for a further 3 weeks significantly reduces the risk of late occurring VTE by 62%. Thromboprophylaxis with LMWH for at least one month should be considered in patients undergoing surgery for malignant disease.     

Prophylaxie primaire de la maladie thromboembolique veineuse chez les patients cancéreux ambulatoires traités par les antinéoplasiques

Patients treated with chemotherapy are at a high risk of venous thromboembolism (VTE), including pulmonary embolisms (PE) and deep vein thrombosis (DVT). The evaluation of the risk of VTE is based on the Khorana risk score or the existence of a thrombogenic neoplasia or treatment. Clinical studies based on this prognostic score are expected. Clinical trials show a benefit of primary prophylaxy of venous thromboembolism with low-molecularweight heparins (LMWHs) for myeloma and advanced or metastatic pancreatic cancers, and it is therefore possible to offer it to patient with a low haemorrhagic risk. The place of primary prevention of VTE in patients with locaaly advanced or metastatic pulmonary cancer is still under debate. In other cases systematic primary prophylaxis is not recommended.