Venous thromboembolism and cancer: guidelines of the Italian Association of Medical Oncology (AIOM)

Structured benefit-risk assessment for enoxaparin, in the context of its label extension, for the extended treatment of deep vein thrombosis and pulmonary embolism, and prevention of its recurrence in patients with active cancer

PURPOSE

Guidelines recommend low-molecular-weight heparins (LMWHs) for patients with cancer-associated thrombosis. However, until recently, only dalteparin and tinzaparin were approved in the European Economic Area (EEA) for these patients. This study compares the benefit-risk profile of enoxaparin with dalteparin and tinzaparin for the extended treatment of deep vein thrombosis (DVT) and pulmonary embolism (PE), and prevention of recurrence in adult patients with active cancer.

METHODS

A semi-quantitative structured benefit-risk assessment was conducted for the label-extension application of enoxaparin based on the benefit-risk action team descriptive framework: define decision context; determine key benefit and risk outcomes; identify data sources; extract data; interpret results.

RESULTS

The key benefits were defined as reduced all-cause mortality and venous thromboembolism (VTE) recurrence (including symptomatic DVT, fatal PE or non-fatal PE); the key risks were major and non-major bleeding of clinical significance, and heparin-induced thrombocytopenia (HIT). Enoxaparin demonstrated comparable effects for the reduction of VTE recurrence and all-cause mortality versus other EEA-approved LMWHs (dalteparin, tinzaparin). There was no evidence of a significant difference between enoxaparin and the comparator groups with regard to incidence of major and non-major bleeding. The data on HIT were too limited to assess the difference between the two groups.

CONCLUSIONS

The assessment demonstrated a favourable benefit-risk profile for enoxaparin similar to that of other EEA-approved LMWHs for the treatment of DVT and PE and the prevention of recurrence in patients with active cancer and thus supported the label-extension approval.

Comparative Effectiveness of Anticoagulants in Patients With Cancer-Associated Thrombosis

Importance

Patterns of clinical utilization and comparative effectiveness of anticoagulants for cancer-associated thrombosis (CAT) remain largely unexplored.

Objectives

To assess patterns of and factors associated with anticoagulant use and to evaluate the comparative effectiveness of contemporary anticoagulants in patients with active cancer in a clinical setting.

Design, Setting, and Participants

This retrospective cohort study obtained deidentified OptumLabs electronic health record claims data from January 1, 2012, to September 30, 2019. Adult patients (≥18 years of age) with a primary cancer diagnosis (except skin cancer) during at least 1 inpatient or 2 outpatient visits within 6 months before the venous thromboembolism (VTE) date were included. Data were analyzed from April 2020 to September 2021.

Exposures

The patients were grouped according to the anticoagulant prescribed: (1) direct oral anticoagulants (DOACs), (2) low-molecular-weight heparin (LMWH), and (3) warfarin.

Main Outcomes and Measures

Odds ratios (ORs) were used to present the association between factors of interest and utilization of anticoagulants. Main efficacy outcomes included risk of VTE recurrence and all-cause mortality. Main safety outcomes included the risk of hospitalization due to major bleeding. Relative treatment effect estimates were expressed as hazard ratios (HRs) with 95% CIs.

Results

This study included 5100 patients (mean [SD] age, 66.3 [12.3] years; 2670 [52.4%] women; 799 [15.7%] Black, 389 [7.6%] Hispanic, and 3559 [69.8%] White individuals). Overall, 2512 (49.3%), 1488 (29.2%), and 1460 (28.6%) filled prescriptions for DOACs, LMWH, and warfarin, respectively. The median (IQR) treatment duration was 3.2 (1.0-6.5) months for DOACs, 3.1 (1.0-6.8) months for warfarin, and 1.8 (0.9-3.8) months for LWMH. Patients with lung (OR, 2.07; 95% CI, 1.12-3.65), urological (OR, 1.94; 95% CI,1.08-3.49), gynecological (OR, 4.25; 95% CI, 2.31-7.82), and colorectal (OR, 2.26; 95% CI, 1.20-4.32) cancer were associated with increased prescriptions for LMWH compared with DOACs. LMWH (HR, 1.47; 95% CI, 1.14-1.90) and warfarin (HR, 1.46; 95% CI, 1.13-1.87) were associated with an increased risk of VTE recurrences compared with DOACs. LMWH was associated with an increased risk of major bleeding (HR, 2.27; 95% CI, 1.62-3.20) and higher all-cause mortality (HR, 1.61; 95% CI, 1.15-2.25) compared with DOACs.

Conclusions and Relevance

In this comparative effectiveness study of claims-based data, patients with CAT received anticoagulation for a remarkably short duration in clinical settings. DOACs was associated with a lower risk of VTE recurrence, major bleeding, and mortality. Warfarin may still be considered for patients with contraindications to DOACs and those with poor persistence on LMWH.

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.

Update on Guidelines for the Management of Cancer-Associated Thrombosis

Cancer-associated thrombosis (CAT) is a major cause of morbidity and mortality in patients with cancer. Over the past 2 decades, enormous advances have been made in the management of CAT. The growing evidence base informing practice has led to the publication of a number of guidelines and guidance documents on the diagnosis and treatment of CAT. The goal of this review is to examine the latest versions of evidence-based guidelines, highlighting the differences and similarities in their methodology, their disease-specific content, and recommendations for management. Our analysis shows that for most clinical topics, the different guidelines provide roughly similar management advice. However, there are a number of important clinical topics in CAT that are not currently covered by the existing guidelines. We think inclusion of these topics in future versions of the guidelines will facilitate ongoing efforts to optimize the care of patients with CAT. IMPLICATIONS FOR PRACTICE: Cancer-associated thrombosis (CAT) is a common complication in patients with cancer. This review examines the differences and similarities of the current CAT guidelines methods and recommendations. Current guidelines largely agree on many aspects of CAT management. However, there are a number of topics in CAT that are not currently included in guidelines where evidence-based guidance would be very helpful for clinicians. Coverage of these topics in future guidelines is encouraged to optimize clinical practice.

Review: Inhibitory potential of low molecular weight Heparin in cell adhesion; emphasis on tumor metastasis

Low molecular weight heparin is a Heparin derivative, produced from commercial-grade Heparin through Chemical or enzymatic depolymerization. LMWH has remained a favored regimen for anticoagulation in cancer patients. Evidence from several studies has suggested that LMWHs possess antitumor and antimetastatic activity aside from their anticoagulant activity. Cancer metastasis is the foremost reason for cancer-related motility rate. Studies have pointed out that adhesion molecules play a decisive role in enhancing recurrent, invasive, and distant metastasis. Therefore, it is hypothesized that Cell adhesion molecules can be determined as a potential therapeutic target group, as antibodies or small-molecule inhibitors could easily access their extracellular domains. Furthermore, data from several investigations have reported LWMH potential effects as antimetastatic agents through influencing cell adhesion molecules. This review's objective is to emphasize the evidence available for the effects of the LMWHs in cell adhesion to inhibit tumor metastasis.

Efficacy and safety of direct oral anticoagulants versus low-molecular-weight heparin in patients with cancer: a systematic review and meta-analysis

The efficacy and safety of direct oral anticoagulants (DOACs) versus low-molecular-weight heparin (LMWH) are still debated in the treatment of patients with cancer, and the optimal duration of therapy remains uncertain. Electronic databases (PubMed, Embase, and Cochrane Library) were searched to retrieve studies on the efficacy and safety of DOACs versus LMWH in treating patients with cancer from January 1980 to October 2018. The primary efficacy and safety endpoints were recurrent venous thromboembolism (VTE) and major bleeding. Our study included two randomized controlled trials (RCTs) and nine observational studies, together comprising 4509 patients with cancer. The pooled estimates indicated that DOACs led to a modest reduction recurrent VTE in the RCTs [RR: 0.63, 95% confidence interval (CI), 0.42-0.96, P = 0.03] and in the observational studies (RR: 0.74, 95% CI, 0.58-0.93, P = 0.011), without increasing the risk of major bleeding for observational studies (P = 0.805), but increased for RCTs (P = 0.017). The same trends were observed in the rivaroxaban subgroup. Moreover, subgroup analyses according to the treatment duration indicated that DOACs significantly reduced the incidence of recurrent VTE (P = 0.006 at 6 months; P < 0.001 at 12 months) without significant differences in major bleeding compared with LMWH at 6 or 12 months. Patients with cancer who received DOACs exhibited a significant reduction in recurrent VTE with no increased risk of major bleeding compared with LMWH. DOACs may be an alternative choice for long-term anticoagulant therapy in patients with cancer.

Low molecular weight heparin and direct oral anticoagulants influence tumour formation, growth, invasion and vascularisation by separate mechanisms

The bidirectional association between coagulation and cancer has been established. However, anticoagulant therapies have been reported to have beneficial outcomes by influencing the vascularisation of the tumours. In this study the influence of a set of anticoagulants on tumour formation, invasion and vascularisation was examined. WM-266-4 melanoma and AsPC-1 pancreatic cancer cell lines were treated with LMWH (Tinzaparin and Dalteparin), and DOAC (Apixaban and Rivaroxaban) and the rate of tumour formation, growth and invasion were measured in vitro. In addition, the influence of these anticoagulants on vascularisation was examined using the chorioallantoic membrane assay (CAM) model and compared to the outcome of treatment with Bevacizumab. Using this model the influence of pharmacological concentrations of the anticoagulant on the growth, invasion and vascularisation of tumours derived from WM-266-4 and AsPC-1 cells was also measured in vivo. Tinzaparin and Daltepain reduced tumour formation and invasion by the cell lines in vitro, but with dissimilar potencies. In addition, treatment of CAM with LMWH reduced the local vascular density beyond that achievable with Bevacizumab, particularly suppressing the formation of larger-diameter blood vessels. In contrast, treatment with DOAC was largely ineffective. Treatment of CAM-implanted tumours with LMWH also reduced tumour vascularisation, while treatment of tumours with Apixaban reduced tumour growth in vivo. In conclusion, LMWH and DOAC appear to have anti-cancer properties that are exerted through different mechanisms.

[Cancer and venous thromboembolism recurrence: The keys for an optimal management]

Low-molecular-weight heparins (LMWH) are to date the standard for 3-to-6-month treatment of cancer-associated thrombosis (CAT) as they are consistently recommended by international clinical practice guidelines. Despite the high risk of VTE recurrence and death in patients with cancer and the favorable benefit-risk profile of LMWH demonstrated in randomized-control studies, the implementation of treatment guidelines remains insufficient in the clinical practice. A systematic review of observational studies, registries and surveys reveals that approximately only 50% of patients with CAT are treated according to practice guidelines while both physicians and patients may be accountable for this situation. Based on the few available published data, we have observed differences between guidelines and clinical practice and we have identified factors influencing patient's management with the perspective to improve adherence to clinical practice guidelines in patients with CAT. Improving the implementation of clinical practice guidelines requires a better knowledge of physician and patient-related factors that influence therapeutic decisions. A global approach of patients with CAT is warranted to optimize the therapeutic management of cancer-associated VTE.

Thromboembolic disease and breathlessness

PURPOSE OF REVIEW

Venous thromboembolism (VTE) comprising deep vein thrombosis and pulmonary embolus, confers a significant symptom burden in the supportive care setting, and yet is often unrecognized. Its management remains challenging because the clinical trials informing practice recruited patients that are largely unrepresentative of the advanced disease populations.

RECENT FINDINGS

Recent years have seen several developments in the management of VTE including new oral anticoagulants, an appreciation of the patient's experience of VTE, and the importance of considering other comorbidities in ensuring an individualized approach to VTE treatment.

SUMMARY

This study reviews the challenges of VTE management within supportive and palliative care, the new oral anticoagulants and the management of VTE in cases in which the evidence is lacking.

Clinical practice guidelines for prophylaxis of venous thomboembolism in cancer patients

Symptomatic venous thromboembolism (VTE) occurs 4-7 times more frequently in cancer patients as compared to non-cancer patients. A significant number of risk factors, which can be subcategorised as patient-, cancer- or treatment-related, have been shown to influence the risk of VTE during malignancy and further incorporated in risk-assessment models. Safe and efficient thromboprophylaxis regimens allow substantial decreased in VTE rates, since VTE is most often a largely preventable disease, but thromboprophylaxis remains underused in cancer compared to non-cancer patients. If thromboprophylaxis is warranted in cancer patients undergoing surgery or hospitalised for acute medical illness or with a lower mobility in the absence of contraindications to anticoagulants, its benefit remains controversial in outpatients and may be limited to locally advanced or metastatic pancreatic or lung cancer treated with chemotherapy. The International Initiative on Thrombosis and Cancer-CME free mobile app (ios and android), based on the International Clinical Practice Guidelines (CPG), facilitates their implementation and dissemination of knowledge worldwide so as to improve VTE treatment and prophylaxis in cancer patients.

The treatment of cancer associated thrombosis: does one size fit all? Who should get LMWH/warfarin/DOACs?

Whilst the term cancer associated thrombosis (CAT) offers an overarching term for all thrombotic events encountered during the cancer journey, the reality is that this is a far too simplistic reflection of a complex multifactorial process occurring within a heterogeneous population. The management of CAT needs to consider factors beyond the thrombus itself: patients must be treated as individuals within the context of their own cancer journey and their preferences for different treatment options. The breath of pathological, pharmacological and psychosocial variants means it is highly unlikely that one treatment regime will be appropriate for all patients. It is inevitable that regimes may need to be modified and anticoagulant agents changed according to clinical and patient preference needs. There is strong evidence supporting the use of low molecular weight heparin first line in the treatment of acute CAT. The evidence for warfarin and the direct acting oral anticoagulants is not as strong but, as oral agents, may be preferred by some patients. This paper shall identify the various treatment options available, factors which will influence the decision making process and when it is justifiable to treat patients differently to the established protocol.

Primary prophylaxis of VTE in cancer outpatients

Cancer patients have a significantly higher risk of developing venous thromboembolism (VTE) compared to non-cancer patients and several studies suggest that VTE risk among ambulatory cancer patients varies widely. Recently, predictive models capable of risk-stratifying a broad range of ambulatory cancer outpatients have been developed and validated; using the Khorana model a score of 2 is associated with an intermediate-high risk for VTE. However, the use of VTE prophylaxis in ambulatory patients who have cancer remains controversial. Even if important randomized clinical trials showed decreased rates of VTE events among patients who were receiving chemotherapy, the effect of prophylaxis on morbidity, mortality, and costs has not been rigorously studied. Outpatients with active cancer should be assessed for thrombosis risk and although most do not routinely require thromboprophylaxis, it should be considered for high risk patients.

Factors influencing adherence to clinical guidelines in the management of cancer-associated thrombosis

International academic and regulatory guidelines consistently recommend the long-term use of low-molecular-weight heparins (LMWHs) as the standard for the treatment of cancer-associated thrombosis (CAT). However, both physicians and patients are reluctant to follow established guidelines. Insufficient compliance with treatment recommendations among care physicians represents a loss of opportunity for patients at very high risk of recurrence of venous thromboembolism (VTE) and death. Few data are available regarding adherence to CAT clinical practice guidelines. Based on published data, we aimed to review the gap between guidelines and practice to draw a more precise picture of current practice in order to precisely identify the extent to which patient management is currently lacking with respect to treatment guidelines. Published observational studies, registries and surveys on cancer-associated VTE treatment were reviewed. In spite of evidence from randomized controlled trials (RCTs) showing the usefulness of long-term LMWH, only approximately 50% of patients are managed according to established guideline recommendations. Patient profiles and co-morbidities influence compliance with standard guidelines. A better knowledge of physician and patient-related factors that influence therapeutic decisions may improve the implementation of clinical practice guidelines. Efficient awareness programs including a multidisciplinary approach are necessary to implement guidelines aimed at optimizing the therapeutic management of cancer-associated VTE.

Venous Thromboembolism in Cancer: An Update of Treatment and Prevention in the Era of Newer Anticoagulants

Cancer patients are at major risk of developing venous thromboembolism (VTE), resulting in increased morbidity and economic burden. While a number of theories try to explain its pathophysiology, its risk stratification can be broadly done in cancer-related, treatment–related, and patient-related factors. Studies report the prophylactic use of thrombolytic agents to be safe and effective in decreasing VTE-related mortality/morbidity especially in postoperative cancer patients. Recent data also suggest the prophylactic use of low molecular weight Heparins (LMWHs) and Warfarin to be effective in reducing VTEs related to long-term central venous catheter use. In a double-blind, multicenter trial, a new ultra-LMWH Semuloparin has shown to be efficacious in preventing chemotherapy-associated VTE’s along with other drugs, such as Certoparin and Nadoparin. LMWHs are reported to be very useful in preventing recurrent VTEs in advanced cancers and should be preferred over full dose Warfarin. However, their long-term safety beyond 6 months has not been established yet. Furthermore, this paper discusses the safety and efficacy of different drugs used in the treatment and prevention of recurrent VTEs, including Bemiparin, Semuloparin, oral direct thrombin inhibitors, parenteral and direct oral factor Xa inhibitors.

Pattern of Venous Thromboembolism Occurrence in Gynecologic Malignancy: Incidence, Timing, and Distribution a 10-Year Retrospective Single-institutional Study

The aim of this single-institutional 10-year retrospective study was to investigate the clinical pattern (incidence, type, timing, and location) of venous thromboembolism (VTE) in Chinese patients with gynecologic cancer. Cases were identified by searching institutional Electronic Discharge Database. A comprehensive review of medical documentation was then performed to collect relevant data. The detection of VTE was symptom-triggered. A total of 155 VTE events were identified out of 7562 cases over the past 10-year period in our hospital. The incidence of clinically significant VTE was 2.0% in gynecologic malignancy, with vulvar cancer (3.7%) and ovarian cancer (2.5%) being the high-risk types (P = 0.01, Chi-square test). Perioperative period (35.1%) and preoperation (29.1%) were the 2 incidence peaks. Seventeen cases of pulmonary embolism (PE) occurred prior to surgery. Ovarian cancer patients were more likely to present preoperative PE compared to other site of cancer (76.4%; P = 0.01, Chi-square test). More preoperative VTE cases were complicated by PE than those in the perioperative period (39.5% vs 17.3%, P = 0.02, Chi-square test). Bilateral lower extremity deep vein thrombosis (DVT) accounted for 32.6% and there existed a preponderance of left-sided DVT (47.5% vs 17.0%, ratio 2.79:1). Femoral vein (36.6%) was the most common location for DVT. About 2.0% of the Chinese patients with gynecologic carcinoma developed clinical VTE, mostly during perioperative period and the time of diagnosis. The true incidence might have been under-estimated due to several reasons. The need for increased patient education and awareness of VTE is of importance.

Characteristic and prognostic implication of venous thromboembolism in ovarian clear cell carcinoma: a 12-year retrospective study

Purpose

To profile the characteristic and prognostic implications of venous thromboembolism (VTE) in Chinese ovarian clear cell carcinoma (CCC) patients.

Methods

We identified all of the cases between 2000 and 2012 by searching our institutional Ovarian CCC Database. A comprehensive review of the medical documentation was performed to collect relevant data. Kaplan-Meier models and Cox regression were employed for survival analysis.

Results

Of the 227 patients, 33 (14.5%) experienced VTE events. There was no significant difference between VTE and non-VTE group patients regarding age, serum cancer antigen 125 or tumor size. The optimal cytoreduction rate was higher in patients without VTE (70.1%) than in those with VTE (51.5%). VTE events were more likely to occur at presentation (36.4%) and recurrence (33.3%), followed by an adjuvant chemotherapy period (18.2%). VTE was more common in patients with advanced-stage disease than those with early-stage disease (P=0.003), whereas pulmonary embolism (PE) was 10-fold as common in advanced-stage disease as in early-stage disease (8.6% vs. 0.8%, P = 0.012). Patients with advanced disease tended to have thrombi in the proximal veins. Two patients died of PE, as confirmed by autopsy. Patients with VTE had reduced survival compared to those without VTE (median overall survival 54 vs. 140 months, P<0.001; median progression-free survival 17 vs. 43 months, P<0.001).

Conclusions

Overall, 14.5% of the patients with ovarian CCC experienced VTE, mainly before their cancer diagnosis or at a time of recurrence. VTE adversely impacted patient survival.

Cancer-associated thrombosis: an overview

Venous thromboembolism (VTE) is a common complication in patients with malignant disease. Emerging data have enhanced our understanding of cancer-associated thrombosis, a major cause of morbidity and mortality in patients with cancer. In addition to VTE, arterial occlusion with stroke and anginal symptoms is relatively common among cancer patients, and is possibly related to genetic predisposition. Several risk factors for developing venous thrombosis usually coexist in cancer patients including surgery, hospital admissions and immobilization, the presence of an indwelling central catheter, chemotherapy, use of erythropoiesis-stimulating agents (ESAs) and new molecular-targeted therapies such as antiangiogenic agents. Effective prophylaxis and treatment of VTE reduced morbidity and mortality, and improved quality of life. Low-molecular-weight heparin (LMWH) is preferred as an effective and safe means for prophylaxis and treatment of VTE. It has largely replaced unfractionated heparin (UFH) and vitamin K antagonists (VKAs). Recently, the development of novel oral anticoagulants (NOACs) that directly inhibit factor Xa or thrombin is a milestone achievement in the prevention and treatment of VTE. This review will focus on the epidemiology and pathophysiology of cancer-associated thrombosis, risk factors, and new predictive biomarkers for VTE as well as discuss novel prevention and management regimens of VTE in cancer according to published guidelines.

Implementing thrombosis guidelines in cancer patients: a review

Venous thromboembolism is a frequent and serious complication in patients with cancer. It is an independent prognostic factor of death in cancer patients and the second leading cause of death, but physicians often underestimate its importance, as well as the need for adequate prevention and treatment. Management of venous thromboembolism in patients with cancer requires the coordinated efforts of a wide range of clinicians, highlighting the importance of a multidisciplinary approach. However, a lack of consensus among various national and international clinical practice guidelines has contributed to knowledge and practice gaps among practitioners, and inconsistent approaches to venous thromboembolism. The 2013 international guidelines for thrombosis in cancer have sought to address these gaps by critically re-evaluating the evidence coming from clinical trials and synthesizing a number of guidelines documents. An individualized approach to prophylaxis is recommended for all patients.

[Cancer-associated venous thromboembolic recurrence: disregard of treatment recommendations]

Low-molecular-weight heparins (LMWH) are the reference curative treatment of venous thromboembolism (VTE) in patients with cancer. All international guidelines recommend the long-term use of LMWH given their demonstrated superiority compared to vitamin-K antagonists (VKA) in reducing VTE recurrence in this patient population without increased risk of bleeding. However, several studies consistently show a lack of adherence to treatment recommendations, which are applied at the very best in 50% of cases. This results in a loss of chance for patients with fragile prognosis and in whom VTE represents the second cause of death. Given the expected benefit and the increased VTE prevalence in patients with cancer, full awareness is necessary to implement programs aiming at improving the therapeutic management of cancer-associated VTE. This requires multidisciplinary consideration by qualified physicians involved in the management of patients with cancer-associated VTE such as oncologists, internists and those specialized in vascular disease and hemostasis.

Adjuvant therapy in breast cancer and venous thromboembolism

Breast cancer patients are considered to be at relatively low risk of developing a TEE. The highest incidence of VTE events occurs in metastatic breast cancer patients likely due to extension of disease, immobility for pathologic bone fractures, cancer cachexia and venous compression by the tumour mass. Although thrombosis is less common in patients with early stage cancer compared to those with more advanced disease, it does occur and is clinically challenging. The adjuvant setting is of particular interest in order to assess the specific thrombogenic potential of systemic chemotherapy, because of the low tumor burden with only microscopic tumor foci at the time of treatment administration. This review summarizes risk factors, incidence and strategies to avoid VTE in breast cancer patients receiving adjuvant therapy.

Coagulation and cancer: biological and clinical aspects

Malignancy affects the hemostatic system and the hemostatic system affects malignancy. In cancer patients there are a number of coagulation abnormalities which provide the background for an increased tendency of these patients to both thrombosis and hemorrhage. The causes of this coagulation impairment rely on general risk factors which are common to other categories of patients, and other factors which are specific to cancer, such as tumor type and disease stage. In addition, data from basic research indicate that the hemostatic components and the cancer biology are interconnected in multiple ways. Notably, while cancer cells are able to activate the coagulation system, the hemostatic factors play a role in tumor progression. This opens the way to the development of bifunctional therapeutic approaches that are both capable of attacking the malignant process and resolving the coagulation impairment. On the other hand, the management of thrombosis and hemorrhages in cancer patients can be different. To approach these problems, some guidelines have been released by prominent international scientific societies. Also actively investigated is the issue of identifying new biomarkers to classify the subjects at a higher risk, thus improving the prevention of thrombohemorrhagic events in these patients. Finally, novel prophylactic and therapeutic approaches are currently under development. This review provides an overview of the hemostatic complications in cancer, together with new insights into the interaction between hemostasis and cancer biology. We also review the assessment of the risk of thrombohemorrhagic events in cancer patients, and the prophylaxis and treatment of such manifestations.

International clinical practice guidelines for the treatment and prophylaxis of thrombosis associated with central venous catheters in patients with cancer

BACKGROUND

Although long-term indwelling central venous catheters (CVCs) may lead to pulmonary embolism (PE) and loss of the CVC, there is lack of consensus on management of CVC-related thrombosis (CRT) in cancer patients and heterogeneity in clinical practices worldwide.

OBJECTIVES

To establish common international Good Clinical Practices Guidelines (GCPG) for the management of CRT in cancer patients.

METHODS

An international working group of experts was set up to develop GCPG according to an evidence-based medicine approach, using the GRADE system.

RESULTS

For the treatment of established CRT in cancer patients, we found no prospective randomized studies, two non-randomized prospective studies and one retrospective study examining the efficacy and safety of low-molecular-weight heparin (LMWH) plus vitamin K antagonists (VKAs). One retrospective study evaluated the benefit of CVC removal and two small retrospective studies were on thrombolytic drugs. For the treatment of symptomatic CRT, anticoagulant treatment (AC) is recommended for a minimum of 3 months; in this setting, LMWHs are suggested. VKAs can also be used, in the absence of direct comparisons of these two types of anticoagulants in this setting [Guidance]. The CVC can be kept in place if it is functional, well-positioned and non-infected and there is good resolution under close surveillance; whether the CVC is kept or removed, no standard approach in terms of AC duration has been established [Guidance]. For the prophylaxis of CRT in cancer patients, we found six randomized studies investigating the efficacy and safety of VKA vs. placebo or no treatment, one on the efficacy and safety of unfractionnated heparin, six on the value of LMWH, one double-blind randomized and one non randomized study on thrombolytic drugs and six meta-analyses of AC and CVC thromboprophylaxis. Type of catheter (open-ended like the Hickman(®) catheter vs. closed-ended catheter with a valve like the Groshong(®) catheter), its position (above, below or at the junction of the superior vena cava and the right atrium) and method of placement may influence the onset of CRT on the basis of six retrospective trials, four prospective non-randomized trials, three randomized trials and one meta-analysis. In light of these data: use of AC for routine prophylaxis of CRT is not recommended [1A]; a CVC should be inserted on the right side, in the jugular vein, and distal extremity of the CVC should be located at the junction of the superior vena cava and the right atrium [1A].

CONCLUSION

Dissemination and implementation of these international GCPG for the prevention and treatment of CRT in cancer patients at each national level is a major public health priority, needing worldwide collaboration.

International clinical practice guidelines for the treatment and prophylaxis of venous thromboembolism in patients with cancer

BACKGROUND

 Guidelines addressing the management of venous thromboembolism (VTE) in cancer patients are heterogeneous and their implementation has been suboptimal worldwide.

OBJECTIVES

To establish a common international consensus addressing practical, clinically relevant questions in this setting.

METHODS

An international consensus working group of experts was set up to develop guidelines according to an evidence-based medicine approach, using the GRADE system.

RESULTS

For the initial treatment of established VTE: low-molecular-weight heparin (LMWH) is recommended [1B]; fondaparinux and unfractionated heparin (UFH) can be also used [2D]; thrombolysis may only be considered on a case-by-case basis [Best clinical practice (Guidance)]; vena cava filters (VCF) may be considered if contraindication to anticoagulation or pulmonary embolism recurrence under optimal anticoagulation; periodic reassessment of contraindications to anticoagulation is recommended and anticoagulation should be resumed when safe; VCF are not recommended for primary VTE prophylaxis in cancer patients [Guidance]. For the early maintenance (10 days to 3 months) and long-term (beyond 3 months) treatment of established VTE, LMWH for a minimum of 3 months is preferred over vitamin K antagonists (VKA) [1A]; idraparinux is not recommended [2C]; after 3-6 months, LMWH or VKA continuation should be based on individual evaluation of the benefit-risk ratio, tolerability, patient preference and cancer activity [Guidance]. For the treatment of VTE recurrence in cancer patients under anticoagulation, three options can be considered: (i) switch from VKA to LMWH when treated with VKA; (ii) increase in LMWH dose when treated with LMWH, and (iii) VCF insertion [Guidance]. For the prophylaxis of postoperative VTE in surgical cancer patients, use of LMWH o.d. or low dose of UFH t.i.d. is recommended; pharmacological prophylaxis should be started 12-2 h preoperatively and continued for at least 7-10 days; there are no data allowing conclusion that one type of LMWH is superior to another [1A]; there is no evidence to support fondaparinux as an alternative to LMWH [2C]; use of the highest prophylactic dose of LMWH is recommended [1A]; extended prophylaxis (4 weeks) after major laparotomy may be indicated in cancer patients with a high risk of VTE and low risk of bleeding [2B]; the use of LMWH for VTE prevention in cancer patients undergoing laparoscopic surgery may be recommended as for laparotomy [Guidance]; mechanical methods are not recommended as monotherapy except when pharmacological methods are contraindicated [2C]. For the prophylaxis of VTE in hospitalized medical patients with cancer and reduced mobility, we recommend prophylaxis with LMWH, UFH or fondaparinux [1B]; for children and adults with acute lymphocytic leukemia treated with l-asparaginase, depending on local policy and patient characteristics, prophylaxis may be considered in some patients [Guidance]; in patients receiving chemotherapy, prophylaxis is not recommended routinely [1B]; primary pharmacological prophylaxis of VTE may be indicated in patients with locally advanced or metastatic pancreatic [1B] or lung [2B] cancer treated with chemotherapy and having a low risk of bleeding; in patients treated with thalidomide or lenalidomide combined with steroids and/or chemotherapy, VTE prophylaxis is recommended; in this setting, VKA at low or therapeutic doses, LMWH at prophylactic doses and low-dose aspirin have shown similar effects; however, the efficacy of these regimens remains unclear [2C]. Special situations include brain tumors, severe renal failure (CrCl<30 mL min(-1) ), thrombocytopenia and pregnancy. Guidances are provided in these contexts.

CONCLUSIONS

Dissemination and implementation of good clinical practice for the management of VTE, the second cause of death in cancer patients, is a major public health priority.

Thromboprophylaxis in non-surgical cancer patients

Acutely ill medical patients with cancer and cancer patients requiring non-surgical therapy are considered as non-surgical cancer patients and are at moderate to high risk of venous thromboembolism (VTE): approximately 10-30% of these patients may develop asymptomatic or symptomatic deep-vein thrombosis (DVT) or pulmonary embolism (PE), and the latter is a leading contributor to deaths in hospital. Other medical conditions associated with a high risk of VTE include cardiac disease, respiratory disease, inflammatory bowel disease, rheumatological and infectious diseases. Pre-disposing risk factors in non-surgical cancer patients include a history of VTE, immobilisation, history of metastatic malignancy, complicating infections, increasing age, obesity hormonal or antiangiogenic therapies, thalidomide and lenalidomide therapy. Heparins, both unfractionated (UFH) and low molecular weight heparin (LMWH) and fondaparinux have been shown to be effective agents in prevention of VTE in the medical setting with patients having a history of cancer. UFH and LMWH along with semuloparin also have a role in outpatients with cancer receiving chemotherapy. However, it has not yet been possible to demonstrate a significant effect on mortality rates in this population. UFH has a higher rate of bleeding complications than LMWH. Thromboprophylaxis has been shown to be effective in medical patients with cancer and may have an effect on cancer outcomes. Thromboprophylaxis in patients receiving chemotherapy remains controversial and requires further investigation. There is no evidence for the use of aspirin, warfarin or mechanical methods. We recommend either LMWH, or fondaparinux for the prevention of VTE in cancer patients with acute medical illnesses and UFH for those with significant severe renal impairment. For ambulatory cancer patients undergoing chemotherapy we recommend LMWH or semuloparin. These are safe and effective agents in the thromboprophylaxis of non-surgical cancer patients.

Systematic screening for occult cancer in elderly patients with venous thromboembolism: a prospective study

BACKGROUND

Cancer is an established risk factor for venous thromboembolism (VTE) and the incidence of cancer increases in the elderly. The benefit of screening for occult cancers in this population is still not clear.

AIM

To evaluate a systematic screening programme for cancer in elderly patients with VTE.

METHODS

This was a prospective study with a 12-month follow-up period. It was conducted in a single centre in consecutive patients over the age of 70 years who had a confirmed diagnosis of VTE. Predefined non-invasive screening techniques for cancer with clinical, laboratory (including tumour markers) and radiological investigations (abdominal ultrasound, chest X-ray and a thoraco-abdominopelvic computed tomography scan) were evaluated.

RESULTS

Fifty patients with a median age of 80 years (range: 70 to 94 years) were included. One patient was diagnosed with chronic lymphocytic leukaemia at inclusion and cancers were found in three other patients during the follow-up period (rectosigmoid adenocarcinoma with hepatic metastases, hepatocellular carcinoma and gastric adenocarcinoma). Only one of the four cancers could have been treated at an earlier stage. The mortality rate of the entire cohort after 12 months was 28%. Two patients died as a direct consequence of cancer.

DISCUSSION

  In this study of elderly patients, a non-invasive screening strategy did not detect several cancers that were subsequently overt clinically. A full history, clinical examination and routine laboratory investigations might be the optimal first-line strategy to detect cancer after the diagnosis of VTE in elderly patients, but regular clinical examinations during follow up are warranted.

Diagnosis and management of people with venous thromboembolism and advanced cancer: how do doctors decide? A qualitative study

BACKGROUND

The treatment of cancer associated thrombosis (CAT) is well established, with level 1A evidence to support the recommendation of a low molecular weight heparin (LMWH) by daily injection for 3-6 months. However, registry data suggest compliance to clinical guidelines is poor. Clinicians face particular challenges in treating CAT in advanced cancer patients due to shorter life expectancy, increased bleeding risk and concerns that self injection may be too burdensome. For these reasons decision making around the diagnosis and management of CAT in people with advanced cancer, can be complex, and should focus on its likely net benefit for the patient. We explored factors that influence doctors' decision making in this situation and sought to gain an understanding of the barriers and facilitators to the application of best practice.

METHODS

Think aloud exercises using standardised case scenarios, and individual in depth interviews were conducted. All were transcribed. The think aloud exercises were analysed using Protocol Analysis and the interviews using Framework Analysis.

PARTICIPANTS

46 participants took part in the think aloud exercises and 45 participants were interviewed in depth. Each group included oncologists, palliative physicians and general practitioners and included both senior doctors and those in training.

SETTING

Two Strategic Health Authority regions, one in the north of England and one in Wales.

RESULTS

The following key issues arose from the data synthesis: the importance of patient prognosis; the concept of "appropriateness"; "benefits and burdens" of diagnosis and treatment; LMWH or warfarin for treatment and sources of information which changed practice. Although interlinked, they do describe distinct aspects of the factors that influence doctors in their decisions in this area.

CONCLUSIONS

The above factors are issues doctors take into account when deciding whether to send a patient to hospital for investigation or to anticoagulate a patient with confirmed or suspected VTE. Many factors interweave and are themselves influenced by and dependent on each other. It is only after all are taken into account that the doctor arrives at the point of referring the patient for investigation. Some factors including logistic and organisational issues appeared to influence whether a patient would be investigated or treated with LMWH for a confirmed VTE. It is important that services are optimised to ensure that these do not hinder the appropriate investigation and management of individual patients.

Risk of venous thromboembolism in patients with cancer: a systematic review and meta-analysis

BACKGROUND

People with cancer are known to be at increased risk of venous thromboembolism (VTE), and this risk is believed to vary according to cancer type, stage of disease, and treatment modality. Our purpose was to summarise the existing literature to determine precisely and accurately the absolute risk of VTE in cancer patients, stratified by malignancy site and background risk of VTE.

METHODS AND FINDINGS

We searched the Medline and Embase databases from 1 January 1966 to 14 July 2011 to identify cohort studies comprising people diagnosed with one of eight specified cancer types or where participants were judged to be representative of all people with cancer. For each included study, the number of patients who developed clinically apparent VTE, and the total person-years of follow-up were extracted. Incidence rates of VTE were pooled across studies using the generic inverse variance method. In total, data from 38 individual studies were included. Among average-risk patients, the overall risk of VTE was estimated to be 13 per 1,000 person-years (95% CI, 7 to 23), with the highest risk among patients with cancers of the pancreas, brain, and lung. Among patients judged to be at high risk (due to metastatic disease or receipt of high-risk treatments), the risk of VTE was 68 per 1,000 person-years (95% CI, 48 to 96), with the highest risk among patients with brain cancer (200 per 1,000 person-years; 95% CI, 162 to 247). Our results need to be considered in light of high levels of heterogeneity, which exist due to differences in study population, outcome definition, and average duration of follow-up between studies.

CONCLUSIONS

VTE occurs in greater than 1% of cancer patients each year, but this varies widely by cancer type and time since diagnosis. The absolute VTE risks obtained from this review can aid in clinical decision-making about which people with cancer should receive anticoagulant prophylaxis and at what times.

Epidemiology, risk and outcomes of venous thromboembolism in cancer

Cancer is associated with a fourfold increased risk of venous thromboembolism (VTE). The risk of VTE varies according to the type of malignancy (i. e. pancreatic cancer, brain cancer, lymphoma) and its disease stage and individual factors (i. e. sex, race, age, previous VTE history, immobilization, obesity). Preventing cancer-associated VTE is important because it represents a significant cause of morbidity and mortality. In order to identify cancer patient at particularly high risk, who need thromboprophylaxis, risk prediction models have become available and are under validation. These models include clinical risk factors, but also begin to incorporate biological markers. The major American and European scientific societies have issued their recommendations to guide the management of VTE in patients with cancer. In this review the principal aspects of epidemiology, risk factors and outcome of cancer-associated VTE are summarized.

The impact of thromboprophylaxis on cancer survival: focus on pancreatic cancer

Pancreatic cancer is still a clinical challenge due to its predominantly late diagnosis and the chemoresistance to cytotoxic and target drugs. One of the major complications of pancreatic cancer is venous thromboembolism (VTE). Both ambulatory and hospitalized pancreatic cancer patients are at higher risk of developing VTE. Among patients with unresectable pancreatic cancer, the occurrence of VTE may be associated with a poor prognosis. Furthermore, emerging clinical data strongly suggest that anticoagulant treatment may improve patient survival by decreasing thromboembolic complications as well as by anticancer activity. Given the clinical relevance for both physicians and basic scientists, this article focuses on the experimental and clinical evidence supporting the relation between the coagulation cascade and the invasive and metastatic potential of pancreatic cancer, and suggests that anticoagulant therapy may represent a useful strategy to improve the prognosis of pancreatic cancer patients.

Venous thromboembolism prophylaxis after hospital discharge: transition to preventive care

Deep vein thrombosis and pulmonary embolism, the common clinical manifestations of venous thromboembolism (VTE), are among the most preventable complications of hospitalized patients. However, survey data repeatedly show poor rates of compliance with guideline-based preventive strategies. This has led the Centers for Medicare and Medicaid Services to deny reimbursement for hospital readmission for thromboembolic complications in patients undergoing total hip or knee arthroplasty. Multiple strategies and national initiatives have been developed to improve rates of VTE prophylaxis during hospitalization; however, most VTE occurs in the outpatient setting. Epidemiologic data suggest that recent surgery or hospitalization is a strong risk factor for the development of VTE and that this risk may persist for up to 6 months. These observations call into question whether VTE prophylaxis should be administered only during hospitalization or if this preventive strategy should be continued after hospital discharge. Many of the randomized trials showing efficacy of VTE prophylaxis have used longer durations of prophylaxis than are typical for current length of hospital stay, highlighting the issue of how long the duration of prophylaxis should be. Several patient groups have undergone formal testing to evaluate the risks and benefits of extended-duration VTE prophylaxis, but this issue is less clear for other categories of patients. Although there is clear consensus that most hospitalized patients should receive VTE prophylaxis, there is uncertainty about whether to continue VTE prophylaxis in the immediate post-hospital period or for an extended duration. The transition from inpatient to outpatient care is a key event in the coordination of continuity of care, but VTE-specific care transition guidance is limited. In this article, we review the evidence for both standard- and extended-duration VTE prophylaxis and discuss the difficulties in effectively maintaining VTE prophylaxis during the transition from inpatient to outpatient care.

[Percutaneous implantable port-related infection and thrombosis: diagnostic and management]

Taking care of patients in oncology needs safety venous access, as percutaneous implantable port. These venous devices are sometimes responsible for serious adverse events. Infection and thrombosis are the two main complications that can occur early or be delayed. Clinical examination and especially, evaluation of the severity are very important keys to manage the patients. They both can lead to the ablation of the central venous device, which is an option to keep always in mind. However, whatever the clinical situation is, the oncologic context such as life expectancy and the need for a venous access is also a data to counterbalance.

Cancer-associated thrombosis: prevention and treatment

Patients with cancer are at high risk to develop venous thromboembolism, and they are also more likely to develop complications from anticoagulant treatment. Because little research has focused on the oncology population to date, the optimal methods of prophylaxis and treatment remain uncertain in some clinical situations. Currently, low molecular weight heparin and warfarin are the most frequently used pharmacologic agents; however, they have their limitations. Other therapeutic options, such as inferior caval filters, are poorly studied and remain controversial. A summary of the most recent evidence on the prevention and treatment of venous thromboembolism in cancer patients is presented here.