Substernal Thyroidectomy

Excerpt

Substernal (or retrosternal) thyroidectomy is the surgical treatment of retrosternal goiters. Retrosternal (or intrathoracic, or substernal, or mediastinal) goiters are defined by deSouza and Smith as thyroid goiters, more than 50% of which are located below the thoracic inlet and into the mediastinum.

Several other definitions have emerged over the years, and thus, there is no clear consensus on the incidence of mediastinal goiters. Different studies report incidence rates from 0,2% to 45% of all goiters.

The majority of substernal thyroid masses are composed of benign multinodular nontoxic goiters. However, the substernal extension of the gland may be a carcinoma. Many substernal masses remain asymptomatic for many years and can oftentimes be discovered incidentally on imaging. Patients can also have neck compression symptoms due to the mass pressing against the trachea, great vessels, or esophagus. The substernal mass often extends into the anterosuperior mediastinum with a usually unilateral extension further into the chest. On occasion, the mass can extend into the posterior mediastinum.

It is generally agreed that thyroxine suppression and radioiodine use are not acceptable as interventions and that surgery is the gold standard in retrosternal goiter management. Surgery comprises of two different approaches; one is transcervical one, in which a cervicotomy is performed, and the other is extracervical. Several different surgical techniques have been described, which will be discussed further in this article. However, no clear consensus exists on the indications for substernal thyroid goiter excision.