Abstract
Background. It has been recognized that lung adenocarcinomas, mucinous bronchioloalveolar cell carcinomas in particular, sometimes spread aerogenously and show an air-space pattern in chest roentgenogram or CT. We report a case of nonmucinous papillary adenocarcinoma showing air-space pattern by extensive aerogenous metastasis. Case. A 73-year-old man was found to have a solitary pulmonary nodule on chest X-ray film and CT. Middle lobe lobectomy was performed and the pathologic diagnosis was moderately differentiated papillary adenocarcinoma. The tumor had a desmoplastic reaction in the central portion. In the peripheral portion, atypical cuboidal cells similar to alveolar epithelial cells lined the alveolar walls and floated in the alveoli. No mucin secretion was found. The tumor partially invaded into the upper lobe across the interlobar fissure. One year later, a solitary metastatic tumor appeared in the right lower lobe. Partial resection of the right lower lobe was performed. Another year later, a nodule appeared in the upper lobe and extensive air-space pattern appeared in the right lower lobe. Right pneumonectomy was performed. The nodule of the upper lobe was papillary adenocarcinoma, identical to the primary cancer. In the lower lobe cancer cells diffusely flooded in the alveoli. Conclusion. The extensive alveolar pattern in this case was reflected by diffuse aerogenous metastasis. This case might be a rare adenocarcinoma characterized by extensive aerogenous metastasis.
