Ischemic venous thrombosis: its hidden agenda

Ischemic venous thrombosis (IVT) is the most severe form of venous thrombosis. The purpose of this article is to describe this rare clinical condition and to review 14 cases of IVT that involve the lower extremities, emphasizing its association with cancer. Between September 1995 and November 1997, 9 women and 5 men, ranging in age from 37 to 75 years (mean 58.6 years), were treated for IVT. Malignancy was the most prevalent risk factor, occurring in 86% (12 of 14) of the patients, and was not diagnosed in 58% (7 of 12) of the cases until after IVT occurred. A postoperative state and a previous history of thrombophlebitis were the next most common risk factors and were equal in frequency (39%). Venous gangrene was present in 79% (11 of 14) of the cases, resulting in 11 amputations in 9 patients. The mortality rate was 71% (10 of 14) of the patients, with 40% of the deaths occurring within 2 months of the diagnosis of IVT. These data support the belief that a strong association exists between IVT and cancer and that IVT may precede the diagnosis of cancer, representing a potential marker for an undiagnosed malignancy. Furthermore, the combination of extensive venous gangrene and disseminated cancer has a poor prognosis.