Idiopathic deep vein thrombosis in an apparently healthy patient as a premonitory sign of occult cancer.

An association between migratory venous thrombosis or acute pulmonary embolism and occult cancer has been previously suggested. The relationship between the commoner deep venous thrombosis (DVT) in an otherwise healthy individual and occult cancer is not known. The incidence of cancer in 35 otherwise healthy patients with idiopathic DVT (group A) was compared to 48 patients with DVT due to a known etiology, excluding cancer (group B). In 12 patients of group A (34%), a diagnosis of cancer was established 4-68 months after the DVT episode, compared to 2 patients of group B (4%) (P = 0.001). The origin of the earliest discovered cancer (up to 8 months) was the reproductive organs (ovary, endometrium, prostate, breast), while the later discovered malignancies were of colon, pancreas, lung and a lymphoma. At the initial idiopathic DVT episode, patients found subsequently to have cancer, were older than the control group (P less than 0.01), had hemoglobin concentration lower than 12.4 g/dl (P less than 0.02), and had eosinophil counts higher than 3% (P less than 0.01). A score devised from these parameters could identify 83% of the patients with cancer and 91% of those without malignancy (P = 0.00003). These findings indicate that there is a correlation between idiopathic DVT and occult cancer and that the majority of the patients at risk may probably be identified early by the score devised.