The development of a polypoid intrapulmonary bronchogenic cyst in the bronchial lumen.

Intrapulmonary bronchogenic cysts are rare in adults and most are outside the trachea and bronchi. There are reports of clear link with the trachea, but the cyst itself occurs outside the trachea. Thus, bronchoscopy will not reveal the cause, which often leads to a diagnosis by surgical resection. We herein report an extremely rare case of an intrapulmonary bronchogenic cyst that was located entirely within the left main bronchial lumen. Bronchoscopy revealed a shiny and smooth surface mass with abundant blood vessels in the lumen that blocked the left main bronchus. The patient was successfully treated with bronchoscopic resection and remained stable at 16 months of follow-up. To our knowledge, this is the first reported case of an intrapulmonary bronchogenic cyst located entirely within the bronchial lumen.