Anticoagulation for the initial treatment of venous thromboembolism in patients with cancer

Anticoagulation for the initial treatment of venous thromboembolism in people with cancer

BACKGROUND

Compared with people without cancer, people with cancer who receive anticoagulant treatment for venous thromboembolism (VTE) are more likely to develop recurrent VTE.

OBJECTIVES

To compare the efficacy and safety of three types of parenteral anticoagulants (i.e. fixed-dose low molecular weight heparin (LMWH), adjusted-dose unfractionated heparin (UFH), and fondaparinux) for the initial treatment of VTE in people with cancer.

SEARCH METHODS

We performed a comprehensive search in the following major databases: Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE (via Ovid) and Embase (via Ovid). We also handsearched conference proceedings, checked references of included studies, and searched for ongoing studies. This update of the systematic review is based on the findings of a literature search conducted on 14 August 2021.

SELECTION CRITERIA

Randomised controlled trials (RCTs) assessing the benefits and harms of LMWH, UFH, and fondaparinux in people with cancer and objectively confirmed VTE.

DATA COLLECTION AND ANALYSIS

Using a standardised form, we extracted data - in duplicate - on study design, participants, interventions, outcomes of interest, and risk of bias. Outcomes of interest included all-cause mortality, symptomatic VTE, major bleeding, minor bleeding, postphlebitic syndrome, quality of life, and thrombocytopenia. We assessed the certainty of evidence for each outcome using the GRADE approach.

MAIN RESULTS

Of 11,484 identified citations, 3073 were unique citations and 15 RCTs fulfilled the eligibility criteria, none of which were identified in the latest search. These trials enrolled 1615 participants with cancer and VTE: 13 compared LMWH with UFH; one compared fondaparinux with UFH and LMWH; and one compared dalteparin with tinzaparin, two different types of low molecular weight heparin. The meta-analyses showed that LMWH may reduce mortality at three months compared to UFH (risk ratio (RR) 0.66, 95% confidence interval (CI) 0.40 to 1.10; risk difference (RD) 57 fewer per 1000, 95% CI 101 fewer to 17 more; low certainty evidence) and may reduce VTE recurrence slightly (RR 0.69, 95% CI 0.27 to 1.76; RD 30 fewer per 1000, 95% CI 70 fewer to 73 more; low certainty evidence). There were no data available for bleeding outcomes, postphlebitic syndrome, quality of life, or thrombocytopenia. The study comparing fondaparinux with heparin (UFH or LMWH) found that fondaparinux may increase mortality at three months (RR 1.25, 95% CI 0.86 to 1.81; RD 43 more per 1000, 95% CI 24 fewer to 139 more; low certainty evidence), may result in little to no difference in recurrent VTE (RR 0.93, 95% CI 0.56 to 1.54; RD 8 fewer per 1000, 95% CI 52 fewer to 63 more; low certainty evidence), may result in little to no difference in major bleeding (RR 0.82, 95% CI 0.40 to 1.66; RD 12 fewer per 1000, 95% CI 40 fewer to 44 more; low certainty evidence), and probably increases minor bleeding (RR 1.53, 95% CI 0.88 to 2.66; RD 42 more per 1000, 95% CI 10 fewer to 132 more; moderate certainty evidence). There were no data available for postphlebitic syndrome, quality of life, or thrombocytopenia. The study comparing dalteparin with tinzaparin found that dalteparin may reduce mortality slightly (RR 0.86, 95% CI 0.43 to 1.73; RD 33 fewer per 1000, 95% CI 135 fewer to 173 more; low certainty evidence), may reduce recurrent VTE (RR 0.44, 95% CI 0.09 to 2.16; RD 47 fewer per 1000, 95% CI 77 fewer to 98 more; low certainty evidence), may increase major bleeding slightly (RR 2.19, 95% CI 0.20 to 23.42; RD 20 more per 1000, 95% CI 14 fewer to 380 more; low certainty evidence), and may reduce minor bleeding slightly (RR 0.82, 95% CI 0.30 to 2.21; RD 24 fewer per 1000, 95% CI 95 fewer to 164 more; low certainty evidence). There were no data available for postphlebitic syndrome, quality of life, or thrombocytopenia.

AUTHORS' CONCLUSIONS

Low molecular weight heparin (LMWH) is probably superior to UFH in the initial treatment of VTE in people with cancer. Additional trials focusing on patient-important outcomes will further inform the questions addressed in this review. The decision for a person with cancer to start LMWH therapy should balance the benefits and harms and consider the person's values and preferences.

Treatment of venous thromboembolism in cancer patients: a systematic review and meta-analysis on the efficacy and safety of different direct oral anticoagulants (DOACs)

Background

To evaluate the efficacy and safety of different direct oral anticoagulants (DOACs) compared with low molecular weight heparins (LMWHs) in the treatment of venous thromboembolism (VTE) in cancer patients.

Methods

Literature was searched in databases including Cochrane Library, EMBASE (Ovid), and MEDLINE (PubMed). Eligible studies were included, and data were collected independently by 2 reviewers. We conducted a systematic review of the efficacy and safety of DOACs in the treatment of VTE in cancer patients. The odds ratios (ORs) of different DOACs compared with LMWHs for VTE, deep vein thrombosis (DVT), pulmonary embolism (PE) recurrence, major bleeding, and clinically relevant non-major bleeding (CRNMB), were calculated in meta-analyses and subgroup analyses.

Results

A total of 18 articles were eligible for analyses, including 4 randomized controlled trials (RCTs) and 14 retrospective studies. Both RCTs and retrospective studies confirmed that DOACs decreased the risk of VTE recurrence [RCTs: OR, 0.60; 95% confidence interval (CI), 0.45–0.80; retrospective studies: OR, 0.73; 95% CI, 0.59–0.90] and DVT recurrence (RCTs: OR, 0.54; 95% CI, 0.36–0.80; retrospective studies: OR, 0.20; 95% CI, 0.06–0.63), but not PE recurrence or fatal PE in cancer patients. Subgroup analyses revealed an important role of rivaroxaban in decreasing recurrent VTE. Meanwhile, major bleeding events were not increased in the DOAC group, but the risks of CRNMBs were significantly elevated. Subgroup analyses confirmed the role of rivaroxaban in increasing the risk of major bleeding events and CRNMBs.

Conclusions

Compared with LMWHs, DOACs (especially rivaroxaban) significantly reduce the risk of VTE and DVT, but not PE recurrence, in patients with cancer. Although DOACs did not increase the major bleeding events in pooled analysis, rivaroxaban showed an elevated risk of this adverse effect in subgroup analysis. In addition, the risk of CRNMB events was increased after the application of DOACs including rivaroxaban.

Adjuvant chemotherapy in curatively resected rectal cancer: How valid are the data?

BACKGROUND

According to the result of the Cochrane review published in 2012, postoperative adjuvant chemotherapy (CTx) is associated with a survival benefit for rectal cancer patients operated for cure in comparison to patients who underwent only the surgical resection.

AIM

To analyze the quality of the data supporting the advantage of adjuvant CTx after surgery for rectal cancer. In the times of increasing health care costs, it is imperative to offer the patient an evidence-based therapy that justifies potential side effects as well as costs.

METHODS

Overall survival was selected as endpoint of interest. Among the 21 included papers which analyzed this endpoint, we identified those three publications which have the highest weights to influence the final result. The validity of these papers was analyzed using the CONSORT checklist for randomized controlled trials. We performed a second meta-analysis excluding the three analyzed studies (n = 18) in order to assess their impact on the overall result of the original meta-analysis. Finally, we performed a third meta-analysis excluding all studies (n = 16) which showed a statistically improved overall survival.

RESULTS

The detailed analysis of the three most relevant RCTs according to the items of the CONSORT checklist showed several pitfalls. In up to 47% of the items, inappropriate answers were found. Generally, a lack of information regarding the randomization procedure as well as the absence of allocation concealment, blinded set-up, of intention-to-treat analysis and omission of sample size calculation were common problems of the analyzed studies. The exclusion of these three studies from the meta-analysis did not affect the general result of the meta-analysis, still confirming a survival advantage after adjuvant chemotherapy. After exclusion of single studies with a statistically significant outcome improvement, the meta-analysis of the remaining 16 studies again shows a statistically significant result due in part to a large remaining sample size.

CONCLUSION

The three most powerful publications show substantial deficits. We suggest a more critical appraisal regarding the validity of single studies because a meta-analysis cannot overcome the limitations of individual trials by pooling treatment effect estimates to generate a single best estimate.

Efficacy and safety of thromboprophylaxis in cancer patients: a systematic review and meta-analysis

BACKGROUND

Thrombosis is a common complication in patients with cancer. Whether thromboprophylaxis could benefit patients with cancer is unclear. The aim of this systematic review was to determine the efficacy and safety of thromboprophylaxis in patients with cancer undergoing surgery or chemotherapy.

METHODS

We searched the Cochrane Library, EMBASE, MEDLINE, EBSCOhost, and Web of Science for studies published before May 2018 to investigate whether thromboprophylaxis measures were more effective than a placebo in patients with cancer.

RESULTS

In total, 33 trials with 11,942 patients with cancer were identified. In patients with cancer undergoing surgery, the administration of thromboprophylaxis was associated with decreasing trends in venous thromboembolism (VTE) [relative risk (RR) 0.51, 95% confidence interval (CI) 0.32-0.81] and DVT (RR 0.53, 95% CI 0.33-0.87). In patients with cancer undergoing chemotherapy, the administration of thromboprophylaxis reduced the incidences of VTE, DVT, and pulmonary embolism compared with no thromboprophylaxis (RR 0.54, 95% CI 0.40-0.73; RR 0.47, 95% CI 0.31-0.73; RR 0.51, 95% CI 0.32-0.81, respectively). The pooled results regarding major bleeding showed no significant difference between prophylaxis and no prophylaxis in either the surgical or the chemotherapy groups (RR 2.35, 95% CI 0.74-7.52, p = 0.1482, I2 = 0%; RR 1.30, 95% CI 0.93-1.83, p = 0.1274, I2 = 0%, respectively).

CONCLUSION

Thromboprophylaxis did not increase major bleeding events or the incidence of thrombocytopenia. All-cause mortality was not significantly different between those who received thromboprophylaxis and those who did not. This meta-analysis provides evidence that thromboprophylaxis can reduce the number of VTE and DVT events, with no apparent increase in the incidence of major bleeding in patients with cancer.

The coagulome and the oncomir: impact of cancer-associated haemostatic dysregulation on the risk of metastasis

Patients with cancer are at high risk of both thromboembolic and haemorrhagic events during the course of their disease. The pathogenesis of haemostatic dysfunction in cancer is complex and involves the interplay of multiple factors. There is growing evidence that interactions between malignancies and the coagulation system are not random but can represent coordinated and clinically-significant adaptations that enhance tumour cell survival, proliferation and metastatic potential. A detailed understanding of the interactions between the haemostatic systems and the pathophysiology of metastasis may not only provide insight into strategies that could potentially reduce the incidence of thrombohaemorrhagic events and complications, but could also help design strategies that are capable of modifying tumour biology, progression and metastatic potential in ways that could enhance anticancer therapies and thereby improve overall survival.

Anticoagulation for the initial treatment of venous thromboembolism in people with cancer

BACKGROUND

Compared with people without cancer, people with cancer who receive anticoagulant treatment for venous thromboembolism (VTE) are more likely to develop recurrent VTE.

OBJECTIVES

To compare the efficacy and safety of three types of parenteral anticoagulants (i.e. fixed-dose low molecular weight heparin (LMWH), adjusted-dose unfractionated heparin (UFH), and fondaparinux) for the initial treatment of VTE in people with cancer.

SEARCH METHODS

A comprehensive search included a major electronic search of the following databases: Cochrane Central Register of Controlled Trials (CENTRAL) (2018, Issue 1), MEDLINE (via Ovid) and Embase (via Ovid); handsearching of conference proceedings; checking of references of included studies; use of the 'related citation' feature in PubMed; and a search for ongoing studies. This update of the systematic review was based on the findings of a literature search conducted on 14 January 2018.

SELECTION CRITERIA

Randomized controlled trials (RCTs) assessing the benefits and harms of LMWH, UFH, and fondaparinux in people with cancer and objectively confirmed VTE.

DATA COLLECTION AND ANALYSIS

Using a standardized form, we extracted data in duplicate on study design, participants, interventions outcomes of interest, and risk of bias. Outcomes of interested included all-cause mortality, symptomatic VTE, major bleeding, minor bleeding, postphlebitic syndrome, quality of life, and thrombocytopenia. We assessed the certainty of evidence for each outcome using the GRADE approach.

MAIN RESULTS

Of 15440 identified citations, 7387 unique citations, 15 RCTs fulfilled the eligibility criteria. These trials enrolled 1615 participants with cancer and VTE: 13 compared LMWH with UFH enrolling 1025 participants, one compared fondaparinux with UFH and LMWH enrolling 477 participants, and one compared dalteparin with tinzaparin enrolling 113 participants. The meta-analysis of mortality at three months included 418 participants from five studies and that of recurrent VTE included 422 participants from 3 studies. The findings showed that LMWH likely decreases mortality at three months compared to UFH (risk ratio (RR) 0.66, 95% confidence interval (CI) 0.40 to 1.10; risk difference (RD) 57 fewer per 1000, 95% CI 101 fewer to 17 more; moderate certainty evidence), but did not rule out a clinically significant increase or decrease in VTE recurrence (RR 0.69, 95% CI 0.27 to 1.76; RD 30 fewer per 1000, 95% CI 70 fewer to 73 more; moderate certainty evidence).The study comparing fondaparinux with heparin (UFH or LMWH) did not exclude a beneficial or detrimental effect of fondaparinux on mortality at three months (RR 1.25, 95% CI 0.86 to 1.81; RD 43 more per 1000, 95% CI 24 fewer to 139 more; moderate certainty evidence), recurrent VTE (RR 0.93, 95% CI 0.56 to 1.54; RD 8 fewer per 1000, 95% CI 52 fewer to 63 more; moderate certainty evidence), major bleeding (RR 0.82, 95% CI 0.40 to 1.66; RD 12 fewer per 1000, 95% CI 40 fewer to 44 more; moderate certainty evidence), or minor bleeding (RR 1.53, 95% CI 0.88 to 2.66; RD 42 more per 1000, 95% CI 10 fewer to 132 more; moderate certainty evidence)The study comparing dalteparin with tinzaparin did not exclude a beneficial or detrimental effect of dalteparin on mortality (RR 0.86, 95% CI 0.43 to 1.73; RD 33 fewer per 1000, 95% CI 135 fewer to 173 more; low certainty evidence), recurrent VTE (RR 0.44, 95% CI 0.09 to 2.16; RD 47 fewer per 1000, 95% CI 77 fewer to 98 more; low certainty evidence), major bleeding (RR 2.19, 95% CI 0.20 to 23.42; RD 20 more per 1000, 95% CI 14 fewer to 380 more; low certainty evidence), or minor bleeding (RR 0.82, 95% CI 0.30 to 2.21; RD 24 fewer per 1000, 95% CI 95 fewer to 164 more; low certainty evidence).

AUTHORS' CONCLUSIONS

LMWH is possibly superior to UFH in the initial treatment of VTE in people with cancer. Additional trials focusing on patient-important outcomes will further inform the questions addressed in this review. The decision for a person with cancer to start LMWH therapy should balance the benefits and harms and consider the person's values and preferences.

The safety of low-molecular-weight heparins in the prevention of venous thromboembolism in surgically-treated cancer patients: results of a multicentre observational study

Aim of the study

Despite widespread use of pharmacological prophylaxis, venous thromboembolism (VTE) still constitutes a common complication in cancer patients. The aim of the study was to analyse the safety of low-molecular-weight heparins (LMWH) in the prevention of VTE in surgically-treated cancer patients.

Material and methods

A total of 5207 cancer patients (44.5% men and 55.5% women) aged 16–97 years participated in a prospective observational study conducted in 13 Polish cancer centres in 2005–2008. This cohort included 4782 subjects who were treated surgically and received LMWH as a pharmacological prophylaxis for VTE prior to or after the surgery. The incidence of haemorrhagic complications and thrombocytopaenia was analysed in this cohort, along with intra-hospital mortality.

Results

Mean duration of LMWH administration was 9.4 ±7.8 days. Haemorrhagic complications: heavy (n = 15) or light bleeding (n = 299), were observed in 314 patients (6.5%). A total of 314 patients (6.5%) presented with haemorrhagic complications: heavy (n = 15, 0.3%) or light bleeding (n = 299, 6.3%). Four cases of heavy bleeding: gastrointestinal bleeding (n = 2), retroperitoneal bleeding (n = 1), and central nervous system bleeding (n = 1), were classified as definitely related to LMWH. No significant association was found between the incidence of haemorrhagic complications and the type of administered LWMH (p = 0.523). No cases of thrombocytopaenia or deaths related to administration of LMWH were reported.

Conclusions

LMWH seems to be a safe form of pharmacological prophylaxis for VTE in surgically-treated cancer patients.

Validity of studies suggesting postsurgical chemotherapy for resectable gastric cancer: critical appraisal of randomised trials

Background and aim

In 2013, Diaz-Nieto et al published a Cochrane review to summarise the impact of postsurgical chemotherapy versus surgery alone on survival for resectable gastric cancer. The authors concluded that postsurgical chemotherapy showed an improvement in overall survival. The aim of this article was to assess the validity of four studies included in the Cochrane review and to investigate the impact of an exclusion of these four studies on the result of the meta-analysis.

Methods

Overall survival was selected as endpoint of interest. Among the 34 included papers which analysed this endpoint, we identified the four publications which have the highest weights to influence the final result. The validity of these papers was analysed using the CONSORT (Consolidated Standards of Reporting Trials) checklist for randomised controlled trials. We performed a new meta-analysis without the four studies in order to assess their impact on the general result of the original meta-analysis.

Results

The analysed four studies revealed several inconsistencies: inappropriate answers were found in up to 77% of the items of the CONSORT checklist. Unclear or inadequate randomisation, missing blinded set-up, conflict of interest and lacking intention-to-treat analysis were the most common findings. When performing a meta-analysis excluding the four criticised studies, postsurgical chemotherapy still showed a significant improvement in overall survival. Even when excluding all single studies with a statistically significant outcome by themselves and performing a meta-analysis on the remaining 26 studies, the result remains statistically significant.

Conclusion

The four most powerful publications in the Cochrane review show substantial deficits. We suggest a more critical appraisal regarding the validity of single studies. However, after the exclusion of these four studies, the result of the meta-analysis did not change.

Parenteral anticoagulation in ambulatory patients with cancer

BACKGROUND

Anticoagulation may improve survival in patients with cancer through a speculated anti-tumour effect, in addition to the antithrombotic effect, although may increase the risk of bleeding.

OBJECTIVES

To evaluate the efficacy and safety of parenteral anticoagulants in ambulatory patients with cancer who, typically, are undergoing chemotherapy, hormonal therapy, immunotherapy or radiotherapy, but otherwise have no standard therapeutic or prophylactic indication for anticoagulation.

SEARCH METHODS

A comprehensive search included (1) a major electronic search (February 2016) of the following databases: Cochrane Central Register of Controlled Trials (CENTRAL) (2016, Issue 1), MEDLINE (1946 to February 2016; accessed via OVID) and Embase (1980 to February 2016; accessed via OVID); (2) handsearching of conference proceedings; (3) checking of references of included studies; (4) use of the 'related citation' feature in PubMed and (5) a search for ongoing studies in trial registries. As part of the living systematic review approach, we are running searches continually and we will incorporate new evidence rapidly after it is identified. This update of the systematic review is based on the findings of a literature search conducted on 14 August, 2017.

SELECTION CRITERIA

Randomized controlled trials (RCTs) assessing the benefits and harms of parenteral anticoagulation in ambulatory patients with cancer. Typically, these patients are undergoing chemotherapy, hormonal therapy, immunotherapy or radiotherapy, but otherwise have no standard therapeutic or prophylactic indication for anticoagulation.

DATA COLLECTION AND ANALYSIS

Using a standardized form we extracted data in duplicate on study design, participants, interventions outcomes of interest, and risk of bias. Outcomes of interested included all-cause mortality, symptomatic venous thromboembolism (VTE), symptomatic deep vein thrombosis (DVT), pulmonary embolism (PE), major bleeding, minor bleeding, and quality of life. We assessed the certainty of evidence for each outcome using the GRADE approach (GRADE handbook).

MAIN RESULTS

Of 6947 identified citations, 18 RCTs fulfilled the eligibility criteria. These trials enrolled 9575 participants. Trial registries' searches identified nine registered but unpublished trials, two of which were labeled as 'ongoing trials'. In all included RCTs, the intervention consisted of heparin (either unfractionated heparin or low molecular weight heparin). Overall, heparin appears to have no effect on mortality at 12 months (risk ratio (RR) 0.98; 95% confidence interval (CI) 0.93 to 1.03; risk difference (RD) 10 fewer per 1000; 95% CI 35 fewer to 15 more; moderate certainty of evidence) and mortality at 24 months (RR 0.99; 95% CI 0.96 to 1.01; RD 8 fewer per 1000; 95% CI 31 fewer to 8 more; moderate certainty of evidence). Heparin therapy reduces the risk of symptomatic VTE (RR 0.56; 95% CI 0.47 to 0.68; RD 30 fewer per 1000; 95% CI 36 fewer to 22 fewer; high certainty of evidence), while it increases in the risks of major bleeding (RR 1.30; 95% 0.94 to 1.79; RD 4 more per 1000; 95% CI 1 fewer to 11 more; moderate certainty of evidence) and minor bleeding (RR 1.70; 95% 1.13 to 2.55; RD 17 more per 1000; 95% CI 3 more to 37 more; high certainty of evidence). Results failed to confirm or to exclude a beneficial or detrimental effect of heparin on thrombocytopenia (RR 0.69; 95% CI 0.37 to 1.27; RD 33 fewer per 1000; 95% CI 66 fewer to 28 more; moderate certainty of evidence); quality of life (moderate certainty of evidence).

AUTHORS' CONCLUSIONS

Heparin appears to have no effect on mortality at 12 months and 24 months. It reduces symptomatic VTE and likely increases major and minor bleeding. Future research should further investigate the survival benefit of different types of anticoagulants in patients with different types and stages of cancer. The decision for a patient with cancer to start heparin therapy should balance the benefits and downsides, and should integrate the patient's values and preferences.Editorial note:This is a living systematic review. Living systematic reviews offer a new approach to review updating in which the review is continually updated, incorporating relevant new evidence, as it becomes available. Please refer to the Cochrane Database of Systematic Reviews for the current status of this review.

Prevention and treatment of venous thromboembolism in patients with solid brain neoplasms: results of a survey among Italian physicians

The decision concerning the introduction of primary and secondary prophylaxis of venous thromboembolism (VTE) in patients with solid brain neoplasms and brain metastases is often challenging due to the concomitant increased risk of intracranial hemorrhage and to limited evidence from available literature. A standardized questionnaire composed of nine multiple-choice questions regarding primary VTE prevention in non-surgical patients during high-risk conditions and VTE secondary prevention in patients with a solid brain neoplasm or cerebral metastases was sent via electronic mail to all the members (n = 2420) of the Italian Federation of the Internal Medicine Hospital Executives' Associations (FADOI) in June 2015. Three hundred and fifty two physicians (14.5%) returned it (participants' median age 51 years; females 46.9%). The majority of respondents prescribe primary thromboprophylaxis (usually with heparin) in non-surgical patients with solid brain neoplasms and brain metastases in concomitance with high-risk conditions. Full-dose anticoagulation with either low-molecular-weight heparin or fondaparinux is the preferred option for acute VTE (69.6%), while a reduced dose is chosen by 21.0% of physicians. The presence of a highly vascular brain neoplasm histotype mandates the prescription of a reduced-dose antithrombotic regimen in a minority of respondents. Vena cava filter placement is an option for the treatment of acute VTE in more than 6% of respondents. Anticoagulants are often prescribed for both VTE primary prevention and treatment. In conclusion, physicians' managements are partially in contrast to recent guidelines, reinforcing the need for educational programs and other studies in this setting.

The creation and implementation of an outpatient pulmonary embolism treatment protocol

The ability to rapidly and accurately risk-stratify patients with venous thromboembolism (VTE), and the availability of direct acting oral anticoagulants have reduced the need for intravenous anticoagulation for patients with deep vein thrombosis (DVT) and pulmonary embolism (PE). Emergency physicians are generally reluctant to discharge patients with VTE without defined and reliable follow up in place, and VTE patients treated with anticoagulants can be at risk for complications related to recurrent VTE and bleeding. In addition, screening for associated diseases (e.g. cancer, hypercoagulable states) may be indicated. Therefore, the outpatient treatment of low risk VTE requires coordinated effort and reliable follow up. By leveraging detailed outcome data and collaborative relationships, we have created a protocol for the safe outpatient treatment of patients with low risk DVT and PE. Our protocol is data driven and designed to address barriers to outpatient VTE management. We expect our protocol to result in improved patient satisfaction, more efficient emergency department (ED) throughput, and decreased cost. Applied nationally, the outpatient treatment of select patients with DVT and PE could have major public health and economic impact.

Tinzaparin for Long-Term Treatment of Venous Thromboembolism in Patients With Cancer: A Systematic Review and Meta-Analysis

Patients with cancer are at increased risk of recurrent venous thromboembolism (VTE) and bleeding. Thus, long-term treatment with anticoagulants for secondary prevention is challenging. The objective of this review was to evaluate current evidence on the safety and efficacy of tinzaparin compared with other anticoagulants for long-term VTE treatment in patients with cancer. Based on a preregistered protocol, we identified randomized controlled trials (RCTs) comparing long-term tinzaparin (therapeutic dose: 175 IU/kg) versus other anticoagulants for at least 3 months after an acute episode of VTE that included adult patients with underlying malignancy. We extracted predefined, clinically relevant outcomes of patients with cancer and, using standard methodology, pooled available data and assessed risk of bias and quality of evidence for each study. Three open-label RCTs evaluating 1169 patients with cancer were included in the analysis. Tinzaparin was associated with a significantly lower risk of recurrent VTE at the end of treatment (relative risk [RR], [95% confidence interval] 0.67 [0.46-0.99]) and at longest follow-up (RR: 0.58 [0.39-0.88]) and showed a lower risk of clinically relevant non-major bleeding at the end of treatment (RR: 0.71 [0.51-1.00]). No significant between-treatment differences were found for all-cause mortality (RR: 1.09 [0.91-1.30]) or fatal and non-fatal major bleeding events (RR: 1.06 [0.56-1.99]). The overall quality of evidence was deemed moderate, mainly due to small sample size in 2 of the studies and limited number of events in the meta-analyses. In conclusion, both short- and long-term treatments with tinzaparin were found to be superior to vitamin K antagonists for avoiding recurrences of VTE.

L-asparaginase and venous thromboembolism in acute lymphocytic leukemia

The occurrence of venous thromboembolism (VTE) in acute lymphocytic leukemia patients receiving L-asparaginase therapy may cause significant morbidity, neurological sequela and possibly worse outcomes. The prophylactic use of antithrombin infusion (to keep antithrombin activity >60%) or low molecular weight heparin (LMWH) may reduce the risk of VTE. The decision to continue L-asparaginase therapy after the development of VTE should be based on anticipated benefits, severity of VTE and the ability to continue therapeutic anticoagulation. In patients receiving asparaginase rechallenge, the use of therapeutic LMWH, monitoring of anti-Xa level and antithrombin level are important. Novel oral anticoagulants are not dependent on antithrombin level, hence offer theoretical advantages over LMWH for the prevention and therapy of asparaginase-related VTE.

Prophylaxis and treatment of venous thromboembolism in patients with cancer: the Saudi clinical practice guideline

BACKGROUND AND OBJECTIVES

Venous thromboembolism (VTE) is commonly encountered in the daily clinical practice. Cancer is an important VTE risk factor. Proper thromboprophylaxis is key to prevent VTE in patients with cancer, and proper treatment is essential to reduce VTE complications and adverse events associated with the therapy.

DESIGN AND SETTINGS

As a result of an initiative of the Ministry of Health of Saudi Arabia, an expert panel led by the Saudi Association for Venous Thrombo-Embolism (a subsidiary of the Saudi Thoracic Society) and the Saudi Scientific Hematology Society with the methodological support of the McMaster University working group produced this clinical practice guideline to assist health care providers in evidence-based clinical decision-making for VTE prophylaxis and treatment in patients with cancer.

METHODS

Six questions related to thromboprophylaxis and antithrombotic therapy were identified and the corresponding recommendations were made following the GRADE (Grading of Recommendations, Assessment, Development and Evaluation) approach.

RESULTS

Question 1. Should heparin versus no heparin be used in outpatients with cancer who have no other therapeutic or prophylactic indication for anticoagulation?

RECOMMENDATION

For outpatients with cancer, the Saudi Expert Panel suggests against routine thromboprophylaxis with heparin (weak recommendation; moderate quality evidence).Question 2. Should oral anticoagulation versus no oral anticoagulation be used in outpatients with cancer who have no other therapeutic or prophylactic indication for anticoagulation?

RECOMMENDATION

For outpatients with cancer, the Saudi Expert Panel recommends against thromboprophylaxis with oral anticoagulation (strong recommendation; moderate quality evidence).Question 3. Should parenteral anticoagulation versus no anticoagulation be used in patients with cancer and central venous catheters?

RECOMMENDATION

For outpatients with cancer and central venous catheters, the Saudi Expert Panel suggests thromboprophylaxis with parenteral anticoagulation (weak recommendation; moderate quality evidence).Question 4. Should oral anticoagulation versus no anticoagulation be used in patients with cancer and central venous catheters?

RECOMMENDATION

For outpatients with cancer and central venous catheters, the Saudi Expert Panel suggests against thromboprophylaxis with oral anticoagulation (weak recommendation; low quality evidence).Question 5. Should low-molecular-weight heparin versus unfractionated heparin be used in patients with cancer being initiated on treatment for venous thromboembolism?

RECOMMENDATION

In patients with cancer being initiated on treatment for venous thromboembolism, the Saudi Expert Panel suggests low-molecular-weight heparin over intravenous unfractionated heparin (weak; very low quality evidence).Question 6. Should heparin versus oral anticoagulation be used in patients with cancer requiring long-term treatment of VTE?

RECOMMENDATION

In patients with metastatic cancer requiring long-term treatment of VTE, the Saudi Expert Panel recommends low-molecular-weight heparin (LMWH) over vitamin K antagonists (VKAs) (strong recommendation; moderate quality evidence). In patients with non-metastatic cancer requiring long-term treatment of venous thromboembolism, the Saudi Expert Panel suggests LMWH over VKA (weak recommendation; moderate quality evidence).

Pharmacologic therapies for malignant glioma: a guide for clinicians

This review covers the medical options for malignant gliomas based on the results of recent clinical trials and updated information on molecular markers of prognostic and predictive value. In addition to alkylating agents, the antiangiogenic drug bevacizumab is increasingly used, particularly in cases of recurrence. Supportive care, including antiedema agents, antiepileptic drugs and anticoagulants, represent complementary treatment approaches of the utmost clinical importance.