Coagulation and cancer : Implications for diagnosis and management

Coagulation disorders are a common problem in neoplastic patients and many factors contribute to increase the risk of thromboembolic events in these patients. An hypercoagulable state is induced by malignant cells interacting directly with hemostatic system and activating the coagulation cascade. More sensitive tests to assess an hypercoagulable state in cancer patients have been developed; even though these tests are always altered in cancer patients, none of them possess a clinical significance in terms of predictive value for the occurence of thromboembolism and disease prognosis in the individual patient. The most frequent thromboembolic complications in cancer patients are deep vein thrombosis of the lower extremities and pulmonary embolism; therefore, disseminated intravascular coagulation, thrombotic thrombocytopenic purpura or haemolytic uremic syndrome are special manifestations of neoplastic disease. Diagnosis of idiopathic deep vein thrombosis, in the absence of other risk factors, could indicate the presence of occult malignant disease; however, the need for an extensive work-up to detect malignancy is still controversial. Neoplastic patients showing a thromboembolic event should be treated with unfractioned heparin or, alternatively, with low molecular weight heparins. In order to prevent recurrence, the administration of heparin should be associated and followed by an oral anticoagulant drug. In recent years new approaches in anti-aggregation therapy have been studied, such as COX-inhibitors, cicaprost and ReoPro; further studies are needed to determine the usefulness of these molecules in treatment of malignancies.