[Diaphragmatic Hernia Mimicking Lung Tumor:Report of a Case].

A 59-year-old woman consulted our hospital because of an abnormal shadow on chest X-ray. A chest computed tomography (CT) revealed a tumor on the diaphragm. A diagnosis of lung tumor was suspected and she underwent video-assisted thoracoscopic surgery. The intraoperative findings revealed a tumor through the defect hole in the right diaphragm. Histological examination revealed fibrotic tissue. The final diagnosis was a diaphragmatic hernia. For lung tumors on the diaphragm, diaphragmatic hernia should also be considered in the differential diagnosis.