Presentation of thyroid carcinoma as a thrombosed external jugular vein, with intraluminal tumour thrombus in the great veins.

Carcinoma of the thyroid most commonly presents as an asymptomatic thyroid nodule. Some types of thyroid carcinoma show vascular invasion, but this is usually microscopic.(1,2)It is rare for such invasion to involve the great veins and be macroscopic. There are 18 such reports in the literature to date.(3-12)We report a case of a carcinoma of the thyroid that presented due to the presence of tumour thrombus within the external jugular vein, where thrombus was also seen within the great veins.