Bemiparin in oncology.

An association between cancer and thrombosis has been recognized since 1865. It is considered to be a two-way association; cancer is associated with an increased risk of venous thromboembolism (VTE), whereas activation of the coagulation cascade enhances the proliferation, angiogenesis potential and metastasis of tumour cells. A sizeable proportion of VTE events in cancer patients undergoing major surgery occur after discharge from hospital, suggesting that extended thromboprophylaxis beyond the normal 7-10 days is warranted in these patients. Studies have demonstrated reduced incidences of VTE with extended thromboprophylaxis using low molecular weight heparins (LMWH) and guidelines recommend continuing thromboprophylaxis after discharge in patients who have undergone major cancer surgery, but the evidence is still considered limited and of low quality, and the recommendations have not been widely implemented in clinical practice. Extended prophylaxis with bemiparin was shown to reduce significantly the incidence of major VTE in patients undergoing major cancer surgery in the Cancer, Bemiparin and Surgery Evaluation study, providing further support for the routine use of extended thromboprophylaxis with LMWH in cancer patients. Heparins, particularly LMWH, in addition to preventing VTE in cancer patients, can block tumour cell growth, invasion, metastasis and angiogenesis. As with other LMWH, bemiparin and its ultra-low molecular weight derivative, RO-14, appear to be effective in preventing angiogenesis in in-vitro models. Recent clinical studies have demonstrated significant survival advantages when LMWH have been added to chemotherapy in cancer patients. This could be partly due, not only to the prevention of thromboembolic diseases in these patients, but also to 'direct' antineoplastic properties of LMWH. The survival benefits appeared greater in patients with limited cancer, especially limited small cell lung cancer. The Adjuvant Bemiparin in Small Cell Lung Cancer study is assessing the effect of bemiparin on survival in patients with limited small cell lung cancer, and although results are not yet available, preliminary data appear very promising.