Hypercoagulation in Malignancy: Localized by Thromboelastography to the Humoral Phase of Coagulation

Patients with cancer are considered hypercoagulable since their risk of thromboembolic events is significantly higher than patients without cancer. Thromboelastography (TEG) was used to investigate hypercoagulation in cancer patients. TEG continually measures over time the physical visco-elastic properties of blood as it transforms from a free flowing fluid to a gel-like clot. Our hypothesis was that blood from cancer patients would form a clot at a faster rate than blood from non-cancer patients hospitalized for thrombo-embolic disease. We studied 75 patients mean age was 57±14 composed of 46 females and 29 males. The patients were divided into 3 different groups: 14 patients with malignancy and thrombosis, 47 malignancy without thrombosis and 14 thrombosis without malignancy. TEG was performed using whole blood stimulated with two agonists: tissue factor and kaolin. Rate of clot development was increased in the cancer patients with and without thrombosis when compared to non-cancer thrombosis group and was localized to the humoral phase of coagulation (p<0.05). Both tissue factor and kaolin stimulated TEGs showed shortening of the “r” time interval in the cancer patients (reflective of a more rapid rate of activation of humoral coagulation factors) and a larger α=alpha angle (reflective of fibrinogen activity). No difference was observed in the platelet phase of coagulation (MA). Cancer patients treated with erythropoietin did not differ from patients who were not treated. Class of chemotherapeutic agent (alkylating agent, antimetabolite, both or neither) was not correlated with TEG. Tissue type of the patients’ malignancy (adenocarcinoma, lymphoproliferative disease, squamos cell carcinoma or other) did not influence the TEG. We conclude that Cancer patients with and without thrombosis differ when compared non-cancer patients with thrombosis by demonstrating a more rapid rate of clot development in the humoral phase of coagulation.