Floating left innominate vein neoplastic thrombus: a rare case of mediastinal extension of follicular thyroid carcinoma.

Objective: We report a case of advanced follicular thyroid cancer with innominate vein involvement. To our knowledge, this seems to be the first case treated in emergency surgery, reported in literature.

Method: A 59-year-old woman with a five-year history of a large and mainly right-sided cervical mass presented with dyspnea, unilateral arm swelling, facial flushing, and venous congestion. An emergency computed tomography scan revealed a thyroid mass extending into the upper mediastinum with displacement and compression of the right jugular vein and carotid artery and apparent adherence to the superior vena cava and left innominate vein.

Results: An emergency total thyroidectomy was performed by means of a sternotomy. The lower portion of the retrosternal goiter projected directly into the left innominate vein, with tumor floating in its lumen. Removal of the neoplastic thrombus was performed, through an incision in the vein, en bloc with the thyroid mass. Both goiter and thrombus were completely replaced by follicular carcinoma.

Conclusions: Accurate preoperative assessment through contrast-enhanced computed tomography is strongly suggested in the presence of enlarged thyroid gland extending into the mediastinum whenever angioinvasion is suspected. This could prevent blinded maneuvers such as digital externalization of the thoracic component of the gland, which can be fatal in cases of cervico-mediastinal goiter extending into great cervical or mediastinal veins.