High incidence of INR alteration in gastrointestinal cancer patients treated with mini-dose warfarin and 5-fluorouracil-based regimens

Systemic Anticoagulant Prophylaxis for Central Catheter–Associated Venous Thrombosis in Cancer Patients

Objective:

To review the literature regarding the incidence of thrombosis in cancer patients with central venous catheters (CVCs) and weigh the evidence supporting thromboprophylaxis in this patient population.

Data Sources:

Clinical literature was identified by searching MEDLINE (1966–February 2007) using the key search terms malignancy, cancer, catheters, prophylaxis, thrombosis, and central venous catheters.

Study Selection and Data Extraction:

An evaluation of retrospective and prospective clinical trials that studied the use of systemic anticoagulants (eg, warfarin, heparin, and low-molecular-weight heparin [LMWH]) to prevent thrombosis with CVCs was performed. Different patient populations, including those manifesting with solid tumor or hematologic malignancy and those undergoing hematopoietic stem cell transplant, were evaluated for this review.

Data Synthesis:

Thrombosis associated with CVCs is a common complication in cancer patients. Most CVC thrombosis will occur within 30 days after placement, with a majority within 8 days. The incidence may depend on the type of CVC and location of the catheter tip. Despite recommendations against the use of systemic anticoagulation for prophylaxis against CVC thrombosis, a potential role continues to be explored in selected settings. Several variables are noted between published clinical trials, making any comparisons difficult to determine whether any benefit exists. Generally, the use of mini-dose warfarin, LMWH, or low-dose unfractionated heparin did not consistently reach significance in reporting a reduction in CVC thrombosis.

Conclusions:

Available data do not support the routine use of anticoagulants for thromboprophylaxis to prevent CVC-related thrombosis. However, several inconsistencies can be found in the studies done to date. More studies are needed to identify subsets of cancer patients who are at higher risk of developing CVC thrombosis and may benefit from prophylactic systemic anticoagulation.

Venous Thromboembolism in Cancer Patients Undergoing Major Abdominal Surgery: Prevention and Management

Cancer is an important risk factor for venous thrombosis. Venous thromboembolism is one of the most common complications of cancer and the second leading cause of death in these patients. Recent research has given insight into mechanism and various risk factors in cancer patients which predispose to thromboembolism. The purpose of this review is to summarize the current knowledge on the prophylaxis, diagnosis, and management of venous thromboembolism in these patients.

Management of venous thromboembolism in patients with cancer

Patients with cancer are at increased risk of venous thromboembolism (VTE). In these patients VTE is associated with substantial morbidity and complicates the clinical management of cancer. Emerging research indicates a probable detrimental effect of VTE on cancer survival. Although VTE may develop at any stage of cancer disease, the risk of VTE is particularly high in association with three clinical settings including surgery for cancer, use of a central vein catheter (CVC) and chemotherapy. Guidelines recommend post-operative prophylaxis (for at least 7-10 days) for patients undergoing elective cancer surgery. A prolonged prophylaxis (for upto four post-operative weeks) is recommended in cancer patients at high risk for VTE. The role of antithrombotic prophylaxis in the prevention of CVC-related thrombosis remains controversial. The PROTECHT study has recently evaluated the benefit of antithrombotic prophylaxis in cancer patients receiving chemotherapy, showing a statistically significant 50% relative risk reduction in symptomatic thromboembolic events. The international guidelines currently agree in non-recommending routine prophylaxis in ambulatory patients who receive anticancer chemotherapy but suggest an individual risk-based evaluation. To better identify cancer patients at high risk for VTE, simple predictive models have been validated. Further intervention studies are currently on-going to explore the benefit of antithrombotic prophylaxis in individual high-risk groups of patients. The long-term treatment of cancer-related VTE is based on therapeutic doses of LMWH in preference to warfarin. The optimal duration of antithrombotic treatment in cancer patients remains to be fully defined.

Risk factors for catheter-related thrombosis (CRT) in cancer patients: a patient-level data (IPD) meta-analysis of clinical trials and prospective studies

BACKGROUND

Knowledge of independent, baseline risk factors for catheter-related thrombosis (CRT) may help select adult cancer patients who are at high risk to receive thromboprophylaxis.

OBJECTIVES

We conducted a meta-analysis of individual patient-level data to identify these baseline risk factors.

PATIENTS/METHODS

MEDLINE, EMBASE, CINAHL, CENTRAL, DARE and the Grey literature databases were searched in all languages from 1995 to 2008. Prospective studies and randomized controlled trials (RCTs) were eligible. Studies were included if original patient-level data were provided by the investigators and if CRT was objectively confirmed with valid imaging. Multivariate logistic regression analysis of 17 prespecified baseline characteristics was conducted. Adjusted odds ratios (ORs) and 95% confidence intervals (CIs) were estimated.

RESULTS

A total sample of 5636 subjects from five RCTs and seven prospective studies was included in the analysis. Among these subjects, 425 CRT events were observed. In multivariate logistic regression, the use of implanted ports as compared with peripherally implanted central venous catheters (PICCs), decreased CRT risk (OR, 0.43; 95% CI, 0.23-0.80), whereas past history of deep vein thrombosis (DVT) (OR, 2.03; 95% CI, 1.05-3.92), subclavian venipuncture insertion technique (OR, 2.16; 95% CI, 1.07-4.34) and improper catheter tip location (OR, 1.92; 95% CI, 1.22-3.02), increased CRT risk.

CONCLUSIONS

CRT risk is increased with use of PICCs, previous history of DVT, subclavian venipuncture insertion technique and improper positioning of the catheter tip. These factors may be useful for risk stratifying patients to select those for thromboprophylaxis. Prospective studies are needed to validate these findings.

Low molecular weight heparin administration in cancer patients with hypercoagulability-related complications and carrying brain metastases: A case series study

Background. Venous thromboembolism (VTE) and brain metastases (MTS) are significant clinical problems in the cancer patient population. Brain MTS and deep vein thrombosis are life-threatening conditions because of the risk of fatal endocranic hypertension and pulmonary embolism. Low molecular weight heparin (LMWH) is a major treatment for cancer patients suffering from VTE with regard to the management of the acute phase and subsequent secondary prophylaxis. Treatment with anticoagulants is feared because of the risk of triggering a massive intracranial hemorrhage.

Methods. The medical records of patients with hypercoagulability-related complications and carrying brain MTS treated with LMWH, in a 10-year period, were scrutinized. The authors aimed to focus on the occurrence of intracranial hemorrhage in anticoagulated patients; furthermore, data were collected with regard to the characteristics of the administered LMWHs along with the duration and dosing of the anticoagulative treatment.

Results. A total of 38 patients (pts) carrying an intracranial metastatic tumor were administered LMWHs: calcium nadroparin (32 pts); enoxaparin (2 pts); reviparin (2 pts); parnaparin (2 pts). Reason for LMWH therapy: deep vein thrombosis and/or pulmonary embolism (15 pts); superficial thrombophlebitis (15 pts); intracardiac thrombus (1 pt); mild DIC (5 pts); acute DIC (1 pt); Raynaud phenomenon (1 pt); atrial fibrillation (1 pt). Median duration of LMWH therapy: 13 weeks (range 1–52). None of the patients developed clinical and/or radiographic findings imputable to intracranial hemorrhage.

Conclusion. There is no standard medical approach for the management of patients who require anticoagulant treatment and are suffering from brain MTS. These patients as necessary, might be anticoagulated with LMWH and its dose reduction is to be considered.

Successful administration of a low dose of calcium nadroparin in patients suffering from pulmonary embolism and brain metastases: a report of two cases

Objective. To focus on the optimal management of thromboembolic complication in patients who have undergone chemotherapy with concomitant brain metastases and referred to a Division of Clinical Oncology.

Background. Thromboembolic diseases are common events in cancer patients due to clotting activation by tumor cells. On the other hand, brain metastases are common complication of systemic cancers. Postmortem studies show that a quarter of patients dying from cancer have intracranial metastases. Brain metastases and pulmonary embolism are life-threatening conditions because of the risk of fatal endocranic hypertension and severe dyspnea. Calcium nadroparin is a low molecular weight heparin usually administered in patient with venous thromboembolism at a dose level of 180 IU/kg/daily.

Case summaries. The authors report the cases of two patients with intracranial metastases and pulmonary embolism-related dyspnea successfully treated with low dose of calcium nadroparin. A patient suffering from metastatic breast cancer and another one with metastatic nonsmall cell lung cancer were recently referred to our department because of severe dyspnea occurring during chemotherapy treatment. Both patients had cerebellar intracranial metastases. Massive pulmonary embolisms were shown by means of the computerized tomography. Despite the administration of a lower heparin dose than the usual one, around three-quarters of the calcium nadroparin daily conventional dose, quickly regressed dyspnea. Significant pulmonary embolism regression was revealed with computerized tomography scan within 8 weeks from the beginning of the thromboembolic complications. None of the patients showed any heparin treatment-related complications.

Conclusion. The authors conclude that, with regard to cancer patients carrying brain metastases who require anti-coagulant therapy, increased risk of intracranial hemorrhage should be kept in mind. An initial low molecular weight heparin dose reduction could be effective, and safely administered, also in case of pulmonary embolism with severe dyspnea.

2008 SOR guidelines for the prevention and treatment of thrombosis associated with central venous catheters in patients with cancer: report from the working group

BACKGROUND

In view of the lack of recommendations on central venous catheter (CVC)-associated thrombosis in cancer patients, we established guidelines according to the well-standardized Standards, Options and Recommendations methodology.

MATERIAL AND METHODS

A literature review (1990-2007) on CVC-associated thrombosis was carried out. The guidelines were developed on the basis of the corresponding levels of evidence derived from analysis of the 36 of 175 publications selected. They were then peer reviewed by 65 independent experts.

RESULTS

For the prevention of CVC-associated thrombosis, the distal tip of the CVC should be placed at the junction between the superior cava vein and right atrium; anticoagulants are not recommended. Treatment of CVC-associated thrombosis should be based on the prolonged use of low-molecular weight heparins. Maintenance of the catheter is justified if it is mandatory, functional, in the right position, and not infected, with a favorable clinical evolution under close monitoring; anticoagulant treatment should then be continued as long as the catheter is present.

CONCLUSIONS

Several rigorous studies do not support the use of anticoagulants for the prevention of CVC-associated thrombosis. Treatment of CVC-associated thrombosis relies on the same principles as those applied in the treatment of established thrombosis in cancer patients.