Conditions: Advanced Pancreatic, Colon, Lung, Gastric and Ovarian Cancer
Keywords: enoxaparin
Allocation: RANDOMIZED | Intervention model: PARALLEL
Enrollment: 70
Healthy volunteers: no

Brief summary:
Research studies have shown a strong association between cancer and blood clots in the veins (also known as deep vein thrombosis). These blood clots can flow to the lungs (pulmonary embolism) which in severe cases may be life threatening. The purpose of this research study is to see if enoxaparin is effective in preventing blood clots in the veins in participants who have cancer of the pancreas, colorectal, non-small cell lung, ovary, or gastric and also have high levels of tissue factor bearing microparticles in their blood (TFMP). TFMP are small particles that are generated from different types of blood cells in the body. In people who have cancer, TFMP are thought to be generated from cancer cells and may represent a risk factor for deep vein thrombosis. Enoxaparin has been used to prevent formation of blood clots in patients after abdominal or orthopedic surgery and in patients who suffer from a severe medical illness. Based on these studies, we are investigating to see if it prevents thrombosis in people with certain types of cancer.

Detailed description:
The study was a randomized phase II trial to evaluate the cumulative incidence of VTE in cancer outpatients. At baseline, measurement of tissue factor-bearing microparticles (TFMP) was performed by impedance-based flow cytometry based on established methods. (Zwicker et al, 2009) Patients were classified as having high or low TFMP levels based on a reference repository of plasmas from sixty cancer patients. The top tercile of tissue factor-bearing microparticle concentrations from the reference specimens (3.5 x 104 microparticles/µl) was considered a cutoff for "high" and corresponds with previously described "detectable" levels. Patients with high levels were randomized (2:1) to enoxaparin 40 mg subcutaneously once daily or observation. Randomization was stratified based on cancer diagnosis. Low TFMP patients were observed without anticoagulation. Both the treating physicians and patients were blinded to microparticle status in the observation arms.

Arms:
arm 1: Patients received enoxaparin 40 mg subcutaneously once daily for 2 months (60 days).Only patients with high TFMP status at baseline were randomized to treatment or observation. arm 2: Patients undergo observation until evaluation with a lower extremity ultrasound at 2 months (day 60). Only patients with high TFMP status at baseline were randomized to treatment or observation. arm 3: Patients undergo observation until evaluation with a lower extremity ultrasound at 2 months (day 60). Patients with low TFMP status at baseline were directly assigned to observation.

Interventions: intervention 1: Enoxaparin
Intervention descriptions: intervention 1: None

Protocol document: