Risk of venous thromboembolism in lung cancer

Purpose of review To evaluate venous thromboembolism (VTE) risk factors in lung cancer patients. Recent findings VTE incidence is around 40-100 cases per 1000 person-years in lung carcinoma patients vs. an estimated 1-2 cases per 1000 person-years in the general population. Patients with adenocarcinoma have higher risk of VTE than patients with squamous cell lung carcinoma. VTE risk appears two-fold higher in nonsmall-cell lung cancer than in small-cell lung cancer patients. Other risk factors are pneumonectomy, metastatic disease, use of specific chemotherapeutic drugs in combination with novel targeted drugs, such as antiangiogenic agents, and elevated prechemotherapy platelet counts. Tissue factor (TF), the initiator of the clotting cascade, may be (over)expressed in lung carcinoma cells. Active TF-bearing microparticles, which may originate from the tumour cells themselves, have been found in the circulation of cancer patients. Microparticle-associated TF activity may provide a link between cancer and thrombosis and play a decisive role in the pathogenesis of the prothrombotic state in cancer patients. Summary Risk factors of VTE in lung cancer patients are adenocarcinoma, metastatic disease, pneumonectomy and anticancer therapy including chemotherapy and anti-VEGF targeted drugs. Other risk factors include pretreatment platelet counts and active TF-expressing circulating microparticles.