Summary. 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.

Summary. 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.

Purpose: Venous thromboembolism (VTE) is an increasingly frequent complication of cancer and its treatments, and is associated with worsened mortality and morbidity in patients with cancer. Design: The Italian Association of Medical Oncology, the National Comprehensive Cancer Network, the American Society of Clinical Oncology, the French National Federation of the League of Centers Against Cancer, and the European Society of Medical Oncology have recently published guidelines regarding VTE in patients with cancer. This review, authored by a working group of members from these panels, focuses on the methodology and areas of consensus and disagreement in the various clinical guidelines as well as directions for future research. Results: There is broad consensus regarding the importance of thromboprophylaxis in hospitalized patients with cancer, including prolonged prophylaxis in high-risk surgical patients. Prophylaxis is not currently recommended for ambulatory patients with cancer (with exceptions) or for central venous catheters. All of the panels agree that low molecular weight heparins are preferred for the long-term treatment of VTE in cancer. Areas that warrant further research include the benefit of prophylaxis in the ambulatory setting, the risk/benefit ratio of prophylaxis for hospitalized patients with cancer, an understanding of incidental VTE, and the impact of anticoagulation on survival. Conclusion: We call for a sustained research effort to investigate the clinical issues identified here to reduce the burden of VTE and its consequences in patients with cancer.

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.