Trousseau's Syndrome Causing Refractory Deep Venous Thrombosis.

A 66-year-old man, who had been diagnosed with deep venous thrombosis (DVT), and who was treated with a vitamin K antagonist (VKA) and who had undergone the implantation of an inferior vena cava filter, was admitted due to an exacerbation of DVT. VKA was administered again; however, the patient's DVT worsened. Further examinations revealed colon cancer, which led to a diagnosis of Trousseau's syndrome. The regression of the thrombi was confirmed after the administration of heparin and the resection of the tumors. Trousseau's syndrome should always be kept in mind when patients present with refractory venous thrombosis. The administration of heparin, and cancer control are necessary for the effective treatment of thrombosis in such cases.