Substernal goiter

Last revised by Dr Mostafa El-Feky on 17 Sep 2021

Substernal goiter (or retrosternal goiter) is an enlarged thyroid gland with intrathoracic extension.

It remains unclear which goiters are to be termed substernal, but a recently proposed definition is a goiter that requires mediastinal exploration and dissection for complete removal or an intrathoracic component extending >3 cm in the thoracic inlet 1.

Chest x-ray may show a superior mediastinal radiopacity causing the deviation of trachea to the opposite side. The superior margin of the radiopacity/mass is untraceable (cervicothoracic sign).

On ultrasound, the inability to scan the inferior most of the thyroid due to its extension posterior to the sternum makes substernal thyroid likely.

According to one study, the most important CT features in determining the necessity of sternotomy for goiter excision are the presence of an ectopic goiter, total thyroid gland volume and goiter extension below the tracheal carina 3.

Most anterior substernal thyroid goiters are accessed via a transcervical approach. For goiters that cannot be removed via neck dissection, such as those with complicated anatomic extensions or posterior mediastinal involvement, the surgeon may need to incorporate a partial upper sternotomy and clavicular head resection or mini-thoracotomy for adequate exposure.

A surgeon with an understanding of the radiologic reporting of a substernal goiter on a dedicated chest CT might perform a sternotomy instead of a simple low-collar incision for resection of substernal goiter.

Some suggested imaging features may indicate requirement for a thoracic approach with a sternotomy include 8

  • extension of the goiter below the aortic arch
  • extension into the posterior mediastinum
  • a dumbbell shape
  • thoracic component that is wider than the thoracic inlet  

A potential pitfall in the assessment of retrosternal extension is the apparent lower position temporarily assumed by the gland when the arms are raised in the case of imaging aimed at the chest. This can be avoided by having the patient's arms by their side when imaging for retrosternal extension 2

ADVERTISEMENT: Supporters see fewer/no ads

Cases and figures

  • Case 1: multinodular goiter - plain film
    Drag here to reorder.
  • Case 1: multinodular goiter - CT
    Drag here to reorder.
  • Case 2
    Drag here to reorder.
  • Case 3
    Drag here to reorder.
  • Case 4
    Drag here to reorder.
  • Case 4: retrosternal goiter
    Drag here to reorder.
  • Case 5
    Drag here to reorder.
  • Case 6
    Drag here to reorder.
  • Case 7: multinodular goiter with substernal extension
    Drag here to reorder.
  • Case 8
    Drag here to reorder.
  • Case 9: mediastinal goiter
    Drag here to reorder.
  • Case 10: retrosternal extension
    Drag here to reorder.
  • Case 11
    Drag here to reorder.
  • Case 12: retrosternal goiter
    Drag here to reorder.
  • Updating… Please wait.

     Unable to process the form. Check for errors and try again.

     Thank you for updating your details.