This patient with shortness of breath on exertion and a firm nodule in the midline of the neck proved to have a upper tracheal wall based lesion.
The chief differentials in this scenario are a primary tumor and inflammatory conditions. Both are uncommon.
Adenoid cystic carcinomas of the tracheobronchial tree are low-grade tumors. They are the 2nd most common primary tumor of the trachea, after squamous cell carcinoma, albeit all are uncommon.
Adenocystic carcinomas may occur in the salivary glands, airways and breast.