Tracheal bronchus associated with lung cancer: a case report.

Tracheal bronchus is a rarely found congenital bronchial anomaly. It usually originates from the right lateral wall of the trachea at the level < 2 cm above the tracheal bifurcation. The patients usually are asymptomatic, but some may experience recurrent pneumonia, chronic bronchitis, or bronchiectasis. It is very rare for a malignant tumor to grow from this aberrant bronchus. There are only four cases of lung cancer developing from the tracheal bronchus reported in the world literature, and we present a fifth case.