Long-term use of daily subcutaneous low molecular weight heparin in cancer patients with venous thromboembolism: why hesitate any longer?

Cancer disease inducing an acquired hypercoagulable state is a well-established feature. Venous thromboembolism (VTE) occurs in 4% to 20% of the patients and is the second cause of mortality in cancer; VTE incidence is four to six times higher in cancer patients compared to other patients. In the last 10 years, important randomised clinical trials have clearly demonstrated that long-term use of daily subcutaneous low molecular weight heparin (LMWH) is more efficient than Vitamin K antagonists to treat VTE in cancer patients. First Italian, then American and more recently French national guidelines recommend the use of LMWH for 3 to 6 months for curative treatment of VTE in cancer patients with a clearly high level (A) of evidence. Despite convincing data, many physicians have not yet modified their clinical practice, doubting the tolerability of such a long period of subcutaneous injections. In fact, LMWH long-term use appears well tolerated and may also increase cancer patient survival. The aim of this review is to present the scientific rationale for long-term daily subcutaneous LMWH in cancer patients, and to reinforce the favourable benefit/tolerance tolerability ratio with this specific antithrombotic strategy.