Venous thromboembolism and cancer

The literature was reviewed in an attempt to determine whether patients with cancer have an increased risk of venous thromboembolism, i.e. deep vein thrombosis and pulmonary embolism. From case reports it was apparent that various thromboembolic or thrombophlebitic manifestations may be found in a small number of patients, although it is possible that not all cases belong to the same clinical or pathogenetic entity. In clinical series it was found that the risk of postoperative venous thromboembolism was increased in cancer patients, but the possibility that this was due to associated risk factors, rather than to the mere presence of a tumour, could not be excluded. Little is known about patients not undergoing surgery. Retrospective postmortem studies have found more thrombi in patients with malignancy, but a prospective study failed to demonstrate an association between malignancy and pulmonary embolism. It is possible that different types of cancer show various degrees of association with venous thromboembolism. We conclude that further studies should be performed to provide a firm clinical and pathoanatomical basis for investigations into the pathogenesis of venous thromboembolism.