A Case of Tracheal Adenoid Cystic Carcinoma Leading to Horner Syndrome and Right Upper Extremity Paralysis Due to Brachial Plexus Metastasis

<p>Background. Among patients with a primary malignant tumor of the trachea, those with tracheal adenoid cystic carcinoma have a relatively good prognosis. However, perineural invasion beyond gross tumor boundaries has been noted in a few cases. The most common tumor metastasis is hematogenous. Case. A 73-year-old man visited a physician because of a decreased swallowing function and paralysis of the right upper extremity. Horner syndrome on the right side was also noted, and the patient was referred to our department under suspicion of Pancoast syndrome. Chest computed tomography showed a tracheal mass 3 cm in diameter, whereas cervical magnetic resonance imaging indicated a contiguous neuromatous lesion extending from the C5-8 and T1 nerve roots to the brachial plexus on the right side. A bronchoscopic biopsy of the tracheal mass led to a histopathological diagnosis of adenoid cystic carcinoma. Examination of a biopsy specimen from the brachial plexus lesion also indicated adenoid cystic carcinoma, and a diagnosis of distant metastasis from the primary tracheal lesion was determined. The patient was provided the best supportive care. Death from malignancy occurred approximately two years after the diagnosis. Conclusion. We encountered a rare case of tracheal adenoid cystic carcinoma with metastasis to the brachial plexus that caused Horner syndrome and right upper extremity paralysis.</p>