[Moderately differentiated adenocarcinoma of the lung presenting as multiple pulmonary metastases with thin-walled cavities].

A 63-year-old woman was admitted because of diabetes mellitus and abnormal chest radiographic findings. Computed tomographic scan showed a large mass in the S1 region of the right lung and many pulmonary nodules with thin-walled cavities in both lung fields. A transbronchial biopsy specimen revealed moderately differentiated adenocarcinoma of bronchial gland origin. The patient could not receive systemic chemotherapy because of her poor physical status, and died of respiratory failure due to advanced pulmonary metastases. Histopathological examination of an autopsy specimen confirmed the diagnosis of primary bronchial adenocarcinoma with multiple cavitary metastases. The cavity wall consisted of moderately differentiated adenocarcinoma cells, and central necrosis with neutrophil infiltration and fibrin precipitation were recognized. These findings suggest that the mechanism of cavity formation in this case may depend on the ischemic tumor necrosis or colliquative tumor necrosis associated with neutrophil infiltration into the central portion of metastatic lesion.