abstract - EvidenceUpdates: Cochrane Review: Primary prophylaxis for venous thromboembolism in ambulatory cancer patients receiving chemotherapy (including professional commentaries)

Abstract

BACKGROUND:  Venous thromboembolism (VTE) often complicates the clinical course of cancer disease. The risk is further increased by chemotherapy but the safety and efficacy of primary thromboprophylaxis in cancer patients treated with chemotherapy is uncertain. OBJECTIVES:  To assess the efficacy and safety of primary thromboprophylaxis in ambulatory cancer patients receiving chemotherapy.  AUTHORS' CONCLUSIONS:   Primary thromboprophylaxis with LMWH significantly reduced the incidence of symptomatic VTE in ambulatory cancer patients treated with chemotherapy. However, the lack of power hampers definite conclusions on the effects on major safety outcomes, which mandates additional studies to determine the risk to benefit ratio of LMWH in this setting.

Comments from Clinical Raters
Oncology - Breast   A nice Cochrane review of the evidence surrounding the question of outpatient anti-coagulation in asymptomatic ambulatory patients receiving chemotherapy. This vexing clinical problem continues to be actively investigated both with oral and injectable anticoagulants. Routine prophylaxis has not found wide-spread use in cancer patients yet, outside of myeloma therapy with steroids combined with an 'imid' (such as thalidomide or lenalidomid), where daily aspirin as preventative is often recommended. The disappointing, but not surprising, result of this meta-analysis is that more studies are needed before the benefit-risk ratio allows routine use in other settings.
Oncology - Breast The cost-effectiveness aspect of primary thrombo-prophylaxis (in patients receiving chemotherapy) will also need to be considered when discussing this issue.
Oncology - General As usual in SOP, the pertinent question is not answered: i.e. how do we conduct an LMWH RCT against placebo?
Oncology - General A timely review and the results are not surprising. In the absence of an improvement in the risk of PE, it is unclear if practitioners will recommend an additional parenteral medication to a patient population that is already undergoing systemic chemotherapy. A better powered study evaluating the effects of LMWH on tumor progression and survival would be worthwhile.
Oncology - Hematology Best Cochrane review I have seen yet - clinically relevant question for which data is sufficient to require synthesis. Well analyzed and well reported.
Oncology - Lung This is a timely review and meta-analysis of RCTs of prevention of VTE in patients with cancer. This study helps place the recent study of semuloparin (Agnelli et al NEJM 2012; 366:601-609) in perspective.