A 62-year-old woman presented with chronic productive cough, intermittent wheezing, and shortness of breath over a 5-year period. She was a nonsmoker and had no history of environmental exposure to chemicals or dust. Her medical history was notable for nasopharyngeal cancer (NPC) treated with radiation therapy 26 years previously that resulted in mild dry mouth and hoarseness, nasal polyp, and chronic sinusitis. During the past 5 years, she underwent a series of examinations that revealed positive bronchodilator test and mild hyperinflation of lung parenchyma on chest radiograph. She received maintenance therapy with inhaled bronchodilator and corticosteroids, antihistaminics, and xanthine under the impression of chronic asthma and sinusitis, and antibiotics and oral corticosteroids during episodes of acute exacerbation. However, the clinical course fluctuated, with deterioration of symptoms on climatic changes or following upper respiratory tract infection. Even though the patient denied being aware of any episodes of aspiration, she was hospitalized and treated as having aspiration pneumonia on four occasions. Yet, no advanced study was performed to evaluate her swallowing function. Tracing back her history, she experienced occasional choking episodes while drinking, but did not pay attention to them. Over the past year, her symptoms of productive cough and dyspnea worsened, and pulmonary function tests revealed marked decreased FVC and FEV1.