[A case of bronchioloalveolar carcinoma with multiple cystic shadows on chest CT]

A 68-year-old woman was admitted to our hospital in 1998 with shortness of breath on exertion. On the first admission, chest radiography revealed multiple nodular shadows and areas of ground-glass appearance mainly in the basal lung fields, and chest CT scans showed multiple thin-walled cystic lesions in both lung fields. Bronchioloalveolar carcinoma was diagnosed by transbronchial lung biopsy. The CA 19-9 level in the serum was abnormally high. The disease progressed, and the patient died 7 months after diagnosis. We report this case because CT scans showed multiple cystic lesions, which is very rare. The mechanism of cystic formation in this case of lung cancer may have involved disruption of the alveolar structure and enlargement of disrupted spaces or of the check valve mechanism.