Squamous cell carcinoma of the right upper lung congenital tracheal bronchus.

Tracheal bronchus, directly arising from the abnormal tracheal wall, is a rare congenital anomaly of the airway. Lung cancer developing in a tracheal bronchus is even more rare. A 68-year-old man had a mass shadow over the right upper lung on chest radiography. Bronchoscopy revealed an abnormally displaced bronchus stemming from the right side of the tracheal wall, 2 cm above the carina. Arising from this tracheal bronchus was a tumor, a biopsy of which showed squamous cell carcinoma. During surgery, a bronchus arising from the right lateral wall of the trachea and supplying the apical segment of the right upper lobe was found. There was a tumor occluding the lumen of the tracheal bronchus, causing distal obstructive pneumonitis. The patient underwent right upper lobectomy with closure of the tracheal bronchus and radical lymph node dissection. The subsequent pathologic examination of the specimen revealed squamous cell carcinoma with surrounding pneumonitis. Bronchogenic cancers developing in a tracheal bronchus are rarely reported in the English language literature. Surgical resection appears to be the treatment of choice.