Retrosternal Goiter with Tracheal Compression
A 54-year-old man with asthma reports 6 months of progressive breathlessness that is worse lying flat. A firm swelling in the lower anterior neck moves upward on swallowing but not on tongue protrusion, and raising both arms produces facial plethora and neck vein distension. CT shows a midline mass extending from the thyroid bed into the superior mediastinum with tracheal compression. What is the most likely diagnosis?
- A.Anterior mediastinal thymoma
- B.Retrosternal multinodular goiterCorrect
- C.Mediastinal Hodgkin lymphoma
- D.Thyroglossal duct cyst
Explanation
A neck mass that rises with swallowing is attached to the pretracheal fascia and is therefore thyroid in origin, and a midline mass extending from the thyroid bed into the superior mediastinum on CT confirms a retrosternal goiter. Longstanding multinodular goiters enlarge downward through the thoracic inlet along the path of least resistance, where the bony aperture is fixed, so even modest further growth compresses the trachea and great veins. This explains the positional dyspnea, stridor and the positive Pemberton sign, in which arm elevation narrows the thoracic inlet and produces facial plethora and venous congestion. A key trap is attributing progressive dyspnea and wheeze to the patient's known asthma; upper airway obstruction typically causes inspiratory stridor and a flattened inspiratory limb on flow volume loop rather than the expiratory wheeze of asthma, and it does not respond to bronchodilators. Thymoma is an anterior mediastinal mass that does not move with swallowing and is classically associated with myasthenia gravis or red cell aplasia. Mediastinal lymphoma usually presents with B symptoms, lymphadenopathy elsewhere and a bulky lobulated anterior mediastinal mass unattached to the thyroid. A thyroglossal duct cyst is a midline neck swelling that characteristically moves upward with protrusion of the tongue and is a lesion of children and young adults, not a mediastinal compressive mass. Management of a compressive retrosternal goiter is total or near-total thyroidectomy, since radioiodine works too slowly for airway compromise.
Why each option
- A.
- Thymoma sits in the anterior mediastinum, does not move with swallowing and is typically linked to myasthenia gravis.
- B.
- Correct. Movement with swallowing plus a midline mass continuous with the thyroid bed extending into the mediastinum defines a retrosternal goiter.
- C.
- Mediastinal lymphoma causes a bulky anterior mediastinal mass with B symptoms and nodal disease, not a thyroid-attached neck swelling.
- D.
- A thyroglossal duct cyst moves upward with tongue protrusion and does not extend into the mediastinum or compress the trachea.
Reference: Schwartz's Principles of Surgery, 11th ed., 2019, Thyroid; UpToDate 2025, Substernal goiter
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