Tracheal neurilemmoma mimicking bronchial asthma--a dilemma of difficult diagnosis: case report.

Tracheal tumors are often overlooked as a cause of pulmonary symptoms until they reach an advanced state. They are often presented with a prolonged cough and shortness of breath. Most tracheal tumors in adults are cancerous (80% to 90%). Benign tracheal tumors are rare in adult patients. A case history is presented of a 19-year-old patient with a rare tracheal neurilemmoma. He was treated as having bronchial asthma initially, but his signs and symptoms did not improve with traditional therapy. The possibility of the presence of an upper airway obstruction was not raised until the typical "inspiratory tubular sound" was heard. Flow-volume loop testing, bronchoscopy, and three-dimensional computed tomography (3-D CT) confirmed the diagnosis of upper airway obstruction caused by a tracheal tumor. Therefore, surgical intervention rather than bronchoscopic removal was performed without difficulty. The patient was leading a stable life 8 months after a surgical resection. The presence of an upper airway obstruction can be proven by flow-volume loop testing and 3-D CT. Further pathologic confirmation can be accomplished by bronchoscopy. High suspicion of an upper airway obstruction such as a tracheal lesion should be raised when bronchial asthma patients fail to respond to conventional treatment.