What is the appropriate therapy for an intrathoracic (substernal) goiter?
Intrathoracic goiters are typically cervical goiters with mediastinal extension. Although commonly asymptomatic, up to 40% of patients present with compressive symptoms resulting from impingement on the esophagus, airway, vascular structures, or nerves. There is general agreement that medical therapy (thyroid hormone suppression and/or radioiodine) is ineffective for intrathoracic goiters. Controversy exists as to whether there is an increased risk of unexpected malignancy in intrathoracic compared with cervical goiters; however, when cases of incidental microcarcinoma are excluded, there does not appear to be an increased risk of malignancy in intrathoracic goiters. Despite this, the presence of an intrathoracic goiter is considered by many as an indication for thyroidectomy. Because the arterial supply of intrathoracic goiters originates in the neck, the vast majority of these tumors can be resected through a cervical approach. Extension into the posterior mediastinum, malignancy, or compression of the vena cava may necessitate a combined cervical and sternotomy approach, although this is required in < 5% of cases.