Intravascular synovial sarcoma of the external iliac vein and reconstruction with the superficial femoral vein

Intravascular synovial sarcoma is a rare neoplasm that arises in large veins of the junctional zone between the proximal leg and lower trunk in adult women. Herein we report the first case of an intravascular synovial sarcoma of the external iliac vein. It was successfully treated with neoadjuvant radiotherapy, radical excisional surgery, and combined arterial and venous reconstruction. Intravascular synovial sarcoma should be considered in the differential diagnosis of any adult woman with deep venous thrombosis and a mass of the femoral or iliac venous system.