Assessment of hypercoagulability in patients with cancer using the Sonoclot Analyzer and thromboelastography.

Patients with cancer have an increased incidence of thrombosis and abnormal haemostasis detectable by sophisticated laboratory tests. Whether abnormalities in such highly sensitive assays is clinically relevant to bleeding or thrombosis is not clear. The thromboelastograph (TEG) and Sonoclot analyzers assess the coagulation process in whole blood and may therefore be physiologically more relevant than assays of isolated haemostatic components. Blood was collected from healthy volunteers and patients with breast cancer, colorectal cancer or benign disease and tested in the TEG and Sonoclot. Results in the cancer group were compared to appropriately sex-matched controls. The TEG parameters R (P < 0.02), angle (P < 0.05) and MA (P < 0.001) were abnormal in colorectal cancer; up to 8/17 (47%) patients being assessed as hypercoagulable. R (P < 0.05), angle (P = 0.05) and MA (P < 0.001) were abnormal in breast cancer; 2/21 (9%) patients having abnormal results. In the Sonoclot Analyzer, 11/17 (64%) patients with colorectal cancer had a significant increase in clot rate (P < 0.001) while 2/17 had a decreased SonACT time (P = 0.05). 4/21 (19%) breast cancer patients had a significant increase in clot rate (P < 0.001) and the SonACT was shortened (P = 0.05). Platelets and fibrinogen levels were generally normal and only one patient had clinical evidence of thrombosis. There were no significant coagulation changes in patients with benign colon or breast disease. In conclusion, hypercoagulability was detected in a high proportion of breast and colorectal cancer patients by both techniques. The clot rates of the TEG and Sonoclot were significantly correlated but the latter was abnormal in a greater proportion of cancer patients.