Based on findings of a recent study researchers say , cancer patients have a seven-fold increased risk for venous thrombosis, or blood clots in the legs or lungs.
Researchers studied 3,220 patients, ages 18 to 70, who had a blood clot in their legs or lungs. They evaluated different tumor sites, the presence of distant metastases, and carrier status of gene mutations. Patients underwent anticoagulant (anti-clotting) therapy, and then a blood sample was taken. DNA was isolated to determine gene mutations, factor V Leiden and prothrombin 20210A, both linked to thrombosis.
It was found that the overall risk of venous thrombosis was increased by seven-fold in patients with cancer vs. persons without cancer and patients with hematological (blood-related) malignancies had a 28-fold increased risk of venous thrombosis, followed by those with lung cancer and gastrointestinal cancer.
In the first few months after the diagnosis of cancer, the risk of venous thrombosis was highest (53-times greater risk). Patients with cancer with distant metastases had a higher risk compared to patients without distant matastases (20-times greater risk). Cancer patients who also carry the V Leiden mutation had a 12-fold increased risk vs. individuals without cancer and factor V Leiden. Similar results were indirectly calculated for the prothrombin 20210A mutation in patients with cancer.
Thus researchers say for patients with cancer who have an increased risk to develop venous thrombosis, prophylactic anticoagulant therapy may be more cost effective than screening for the factors.