Long-term therapy of venous thromboembolism in cancer patients.

Venous thromboembolism (VTE) is a common complication in cancer patients that results in significant morbidity and mortality. Long-term treatment options for cancer patients who experience VTE include vitamin K antagonists (VKAs), low molecular weight heparins (LMWHs), and inferior vena caval (IVC) filters. Cancer patients have a two- to fourfold higher risk for experiencing recurrent VTE and major bleeding during chronic VKA therapy than patients without malignancies. Recent randomized clinical trials have shown that LMWHs rather than oral VKAs are preferred for initial chronic treatment of VTE in patients with advanced cancer. One factor potentially limiting the broader use of LMWH for chronic therapy in the United States is its higher acquisition cost. Efficacy, cost, drug availability, patient comorbidities, and concomitant medications all need to be considered when selecting chronic VTE therapy. Cancer patients with VTE should be treated for as long as their disease is active to minimize the incidence of recurrence. Use of IVC filters should generally be reserved for patients at high risk for recurrent VTE who have contraindications to anticoagulation. Several new anticoagulants are being investigated that promise greater therapeutic choices and potentially better outcomes for cancer patients with VTE.