Venous Thromboembolism Common and Serious for Cancer Patients

Las Vegas—Approximately 20% of cancer patients suffer from venous thromboembolism (VTE), which is 4 to 7 times more likely in cancer patients than in the general population and can lead to long-term complications. Preventing VTE is possible when treated correctly, according to Michael B. Streiff, MD, medical director for anticoagulation management service and outpatient clinics at Johns Hopkins University. Not all cancer patients are at the same risk for VTE, with those with pancreatic and brain cancer among the higher risk group and leukemia and cervix cancer patients among the lower risk group. The risk also depends on the cancer’s type, histology, and stage, according to Dr. Streiff, who spoke at the Fall Managed Care Forum during a session titled Optimizing the Prevention and Treatment of Venous Thromboembolism in Cancer Patients. Each year, there are 900,000 cases of VTE, a disease category that includes deep vein thrombosis (DVT) and pulmonary embolism. Approximately 10% of hospital deaths are related to VTEs, according to Dr. Streiff, who added that cancer patients are 2 to 3 times more likely to die of VTEs. VTEs also commonly cause long-term morbidity, with 40% of patients experiencing recurrent VTEs by 10 years and postthrombotic syndrome found in 50% of patients within 10 years. However, Dr. Streiff said effective prophylaxis reduces the incidence of DVTs by 60%. Dr. Streiff said all cancer patients should receive inpatient VTE prophylaxis based on the National Comprehensive Cancer Network (NCCN) and American Society of Clinical Oncology (ASCO) guidelines. Pharmacologic prophylaxis such as low-molecular-weight heparin (LMWH), unfractionated heparin (UFH), or fondaparinux is preferred, but patients should receive mechanical prophylaxis if they have a contraindication to anticoagulation treatment. Selected cancer outpatients should also receive prophylaxis, including high-risk cancer surgery patients and myeloma patients receiving thrombogenic chemotherapy. The NCCN recommends initiating prophylaxis therapy early and selecting the agent based on cost, ease of administration, efficacy, half-life, inpatient versus outpatient, and renal function. The NCCN guidelines indicate that patients should initially take LMWH, UFH, or fondaparinux for at least 5 days and then LMWH or warfarin for chronic therapy for as long as the cancer is active or under treatment. For VTEs in patients with a central venous catheter, the NCCN recommends treating for at least 3 months. ASCO recommends using LMWH for the initial 5 to 10 days of anticoagulant treatment and also using LMWH for at least 6 months for long-term anticoagulant therapy. If LMWH is unavailable, vitamin K antagonists with a targeted international normalized ratio of 2 to 3 is acceptable long-term therapy. After 6 months, ASCO suggests patients with active cancer should receive indefinite anticoagulant therapy. In addition, ASCO’s guidelines say that inserting an inferior vena cava filter is only appropriate for patients with contraindications to anticoagulant therapy or for patients with recurring VTE after having adequate long-term therapy with LMWH.