Systemic anticoagulant prophylaxis for central catheter-associated venous thrombosis in cancer patients.

OBJECTIVE: To review the literature regarding the incidence of thrombosis in cancer patients with central venous catheters (CVCs) and weigh the evidence supporting thromboprophylaxis in this patient population. DATA SOURCES: Clinical literature was identified by searching MEDLINE (1966-February 2007) using the key search terms malignancy, cancer, catheters, prophylaxis, thrombosis, and central venous catheters. STUDY SELECTION AND DATA EXTRACTION: An evaluation of retrospective and prospective clinical trials that studied the use of systemic anticoagulants (eg, warfarin, heparin, and low-molecular-weight heparin [LMWH]) to prevent thrombosis with CVCs was performed. Different patient populations, including those manifesting with solid tumor or hematologic malignancy and those undergoing hematopoietic stem cell transplant, were evaluated for this review. DATA SYNTHESIS: Thrombosis associated with CVCs is a common complication in cancer patients. Most CVC thrombosis will occur within 30 days after placement, with a majority within 8 days. The incidence may depend on the type of CVC and location of the catheter tip. Despite recommendations against the use of systemic anticoagulation for prophylaxis against CVC thrombosis, a potential role continues to be explored in selected settings. Several variables are noted between published clinical trials, making any comparisons difficult to determine whether any benefit exists. Generally, the use of mini-dose warfarin, LMWH, or low-dose unfractionated heparin did not consistently reach significance in reporting a reduction in CVC thrombosis. CONCLUSIONS: Available data do not support the routine use of anticoagulants for thromboprophylaxis to prevent CVC-related thrombosis. However, several inconsistencies can be found in the studies done to date. More studies are needed to identify subsets of cancer patients who are at higher risk of developing CVC thrombosis and may benefit from prophylactic systemic anticoagulation.