What is superficial migratory thrombophlebitis (SMT)?

Many conditions may produce a state of increased blood coagulability, leading to venous thrombosis. One important GI-related cause is pancreatic cancer, which may be asymptomatic at the time the thrombophlebitis develops. Fifty percent of cases of SMT are associated with an underlying malignancy.

Superficial migratory thrombophlebitis presents as cropped, tender, erythematous, linear cords along the course of superficial veins of the trunk and extremities. Lesions in one area may be resolving, while new lesions are developing elsewhere. It is essential that any patient presenting with superficial migratory thrombophlebitis undergo a thorough evaluation to rule out underlying malignancy.

Recent work has focused on the association of superficial migratory thrombophlebitis and mucin-secreting abdominal adenocarcinomas. A low-grade disseminated intravascular coagulation occurs through mucin interaction with L and P selectins leading to aggregation and emboli formation, none of which requires thrombin generation. The thrombophlebitis is remarkably resistant to oral anticoagulant therapy such as warfarin, but does respond well to lowmolecular- weight (LMW) heparin therapy, which is postulated to inhibit tumor growth, instead of acting in its traditional anticoagulatory role. Current research indicates that dalteparin and nadroparin may also illicit improved outcomes and survival rates. SMT is not specific for GI malignancies and has also been associated with carcinoma of the lung and breast, Hodgkin’s disease, and multiple myeloma. Nonmalignant associations include Behçet’s disease and rickettsial infections.

Thayalasekaran S, Liddicoat H, Wood E: Thrombophlebitis migrans in a man with pancreatic adenocarcinoma: a case report, Cases J 2:6610, 2009.