[Ectatic tumoral thrombosis of the superior vena cava revealing thyroid cancer]. / Thrombose tumorale ectasiante de la veine cave supérieure révélatrice d'un cancer thyroïdien.

Microscopic angio-invasion by carcinoma of the thyroid is known. Extension into the great veins is much more uncommon. Most of the cases which have been previously described were discovered on post-mortem examination. We report the case of a 55 year-old woman who was found to have an asymptomatic small cervical goiter 6 years ago; during the last 12 months she developed superior vena cave (SVC) syndrome radiological investigation (angiography, CT scan) and surgical exploration showed a carcinoma of the thyroid with intraluminal extension of the tumor leading to thrombosis and ectasia of the SVC. Surgery was performed with resection of the whole thyroid, the SVC and the innominate veins. A double prosthetic venous by pass was then inserted between the innominate veins and right atrium. Five years after resection, the patient has no recurrence or metastatis and no clinical symptom of SVC syndrome. To our knowledge, this is only the third reported case successfully treated by surgery.