Clinical data: A 61-year-old man was referred for evaluation of a thyroid nodule causing a 50% degree of tracheal compression and significant substernal spread. The lower pole of the left lobe was 19 cm below the level of the clavicula. The lesion was revealed on a chest CT scan which was performed because of COVID-19 infection. The patient had no complaints, and he was not aware of any thyroid problem.

Palpation: The thyroid was located inferior to the usual position. The left lobe was palpable and enlarged.

Laboratory tests: TSH 0.05 mIU/L, FT4 14.8 pM/L.

Ultrasonography. Both lobes were echonormal and enlarged, the dimensions of the right lobe were 44, 50 and minimum 80 mm while those of the left lobe were 55, 65 and minimum 90 mm, width, depth and length, respectively. Neither of the lower pole of the lobes was visible during swallowing.

Cytology was performed form the lesion in the right lobe and in benign lesion.

Total thyroidectomy was performed, the surgery had to be extended with thoracotomy. Histopathology disclosed hyperplastic nodules.

Comments.

1. The degree of substernal spread can be judged by comparing the distance between the most ventral and most dorsal part of the lowest visible portion of the thyroid before and during swallowing. In this case, there was no difference between the values which suggested that the thyroid extends far beyond the level of the clavicula.

2. There is a huge individual difference in the extent when a goiter starts causing compression signs.