Endocrine Abstracts

Primary mediastinal ectopic goiters are very rare and comprise about 1% of all mediastinal tumors. Blood supply of primary mediastinal goiter comes from local intrathoracic vessels. Compressing symptoms, diagnostic uncertainty, and the risk of malignancy support surgical excision.

Case report: The patient is a 40-year-old woman with a 6-month history of progressive dyspnea, chest and back pain. Chest X-ray showed the left superior mediastinal mass was compressing the trachea. A computed tomography (CT) scan confirmed a posterior mediastinal (retrotracheal visceral mediastinum) mass with cervical connections. Thoracic biopsy was performed and pathology was colloidal goiter. Hematological and chemistry panels were normal. A left posterolateral thoracotomy was performed. The mass was, behind the arcus aorta, left carotid and subclavian arteries. Although the mass was pushing the trachea through the right hemithorax, there was no invasion. On the other hand, the esophagus was compressed to the right and posterior aspect of the thorax. There was a 13 cm contact between the columna vertebrales and the mass. The specimen was solid, and measured 13×11×10 cm. Histological examination was representative of colloidal goiter.

Discussion: Ectopic intrathoracic thyroid is a rare presentation of thyroid disease and comprises about 1% of all mediastinal tumors. The anterior mediastinum makes up 75–94% of intrathoracic goiters. The posterior mediastinal masses constitute 10–15%. The right posterior mediastinum is the most common location, in which the aortic arch development blocks descent to the left. Symptoms at presentation vary and range from minimal to disabling. These include cough, pain, neck swelling, dysphagia, superior vena cava syndrome, or dysfunction of the recurrent laryngeal nerve. Our patient has admitted to our clinic with progressive dyspnea and stridor.