OBJECTIVES:~Determine the utility of warfarin in reducing thrombosis rates in cancer patients with central venous catheters.~Compare the thrombosis rates in patients treated with different warfarin dosing schedules.~Compare the adverse events and survival of patients receiving or not receiving this drug.~OUTLINE: This is a randomized, multicenter study. Patients are stratified according to sclerosant potential of cytotoxic regimen (low vs high), site of placement of catheter (peripheral vs central), and duration of drug administration (brief infusion (under 24 hours) vs prolonged infusion (24 hours and over)). Patients are randomized to 1 of 3 arms.~Arm I: Patients receive no warfarin.~Arm II: Patients receive oral warfarin daily beginning 3 days before placement of central venous catheter (CVC) and continuing until CVC is removed or thrombosis occurs.~Arm III: Patients receive oral warfarin as in arm II, with dose adjustment after CVC placement to achieve and maintain INR level.~Patients are followed at 12 months.~PROJECTED ACCRUAL: A total of 1,400 patients (400 in arm I, 700 in arm II, and 300 in arm III) will be accrued for this study within 2 years.
RATIONALE: Warfarin may be effective in preventing the formation of blood clots in patients with central venous catheters.~PURPOSE: Randomized clinical trial to study the effectiveness of warfarin in preventing blood clots in cancer patients who have central venous catheters.