Deep-Vein Thrombosis and the Incidence of Subsequent Symptomatic Cancer

In contrast to the established relation between overt cancer and subsequent venous thromboembolism, it is unclear whether symptomatic deep-vein thrombosis is associated with a risk of subsequent overt malignant disease. Two hundred sixty consecutive patients with symptomatic, venographically proved deep-vein thrombosis were enrolled in a study, of whom 250 were followed during a two-year period. Among those assessed during follow-up, the incidence of subsequently detected cancer in the 105 patients with secondary venous thrombosis (i.e., thrombosis associated with a well-recognized risk factor other than cancer) was compared with the incidence of cancer in the 145 patients with idiopathic venous thrombosis. Routine examination at the time of diagnosis of the venous thrombosis revealed cancer in 5 of the 153 enrolled patients with idiopathic venous thrombosis (3.3 percent) and in none of the 107 enrolled patients with secondary venous thrombosis. During follow-up, overt cancer developed in 2 of the 105 patients with secondary venous thrombosis (1.9 percent) and in 11 of the 145 patients with idiopathic venous thrombosis (7.6 percent; odds ratio, 2.3; 95 percent confidence interval, 1.0 to 5.2; P = 0.043). Of the 145 patients with idiopathic venous thrombosis, 35 had confirmed recurrent thromboembolism. Overt cancer subsequently developed in 6 of the 35 (17.1 percent). The incidence of cancer in the patients with recurrent idiopathic venous thrombosis was higher than that in the patients with secondary venous thrombosis (P = 0.008; odds ratio, 9.8; 95 percent confidence interval, 1.8 to 52.2) or in the patients with idiopathic venous thrombosis that did not recur (P = 0.024; odds ratio, 4.3; 95 percent confidence interval, 1.2 to 15.3). There is a statistically significant and clinically important association between idiopathic venous thrombosis and the subsequent development of clinically overt cancer, especially among patients in whom venous thromboembolism recurs during follow-up. (N Engl J Med 1992;327:1128–33.), SINCE the initial observation by Trousseau in 1868 relating thrombotic phenomena to cancer,1 numerous studies have addressed the relation between malignant disease and venous thromboembolism. An increased incidence of venous thromboembolism in patients with known cancers has been convincingly demonstrated. Thus, cohort studies of surgical patients that used mandatory objective tests to confirm the presence of postoperative venous thrombosis showed that the incidence of venous thrombosis was markedly higher in patients with malignant disorders than in patients with other (nonmalignant) diseases.2,3 Furthermore, an increased risk of venous thromboembolism is suggested by the high incidence of pulmonary embolism and subclinical activation… © 1992, Massachusetts Medical Society. All rights reserved.