Deep vein thrombosis as a predictor of cancer.

An association between cancer and venous thrombosis has long been recognized. In an attempt to find whether venous thrombosis can serve as a reliable predictor of subsequent cancer, 196 cases of confirmed venous thrombosis treated over a seven-year period were reviewed. Of a total of 196 cases, 113 were found to suffer from primary type deep venous thrombosis (DVT), whereas 83 were allocated to secondary type DVT. Of 113 cases with primary DVT, 23 had suffered from recurrent episodes, whereas 90 had only a single episode. From the secondary DVT group of 83 patients, 14 suffered from recurrent episodes and 69 had a single episode. Of the patients in the primary DVT group, 2.65% (3/113) developed cancer subsequently, whereas none was detected among the group of 83 patients who had secondary DVT. In the group of 113 patients with primary DVT, the incidence was higher among those who had recurrent episodes (4.34%, 1/23) than among those who had a single episode (2.22%, 2/90). The overall incidence of cancer among 196 cases of DVT was found to be 1.53% (3/196). The findings do not support the routine screening of all DVT patients by expensive diagnostic modalities. These patients should rather be assessed by careful clinical examinations and baseline investigations. The detailed investigations should be resorted to if there is any suggestion of presence of occult malignancy by these simpler means. One should be more vigilant in case of patients suffering from primary type DVT, for the incidence in this group is significantly higher.