[Pulmonary Fetal Adenocarcinoma Requiring Differential Diagnosis of Metastatic Lung Tumor;Report of a Case].

Fetal adenocarcinoma is a rare disease. We report a case of fetal adenocarcinoma requiring differential diagnosis of metastatic lung tumor. A 75- year-old woman was pointed out a 8 mm tumor in the right lower lobe by chest computed tomography(CT) 6 month ago. Because the size of the tumor had been increasing for 6 months, she was hospitalized for surgery. Because of the tumor shape, we suspected that the tumor was metastatic lung tumor of hepatocellular carcinoma for which she had undergone hepatic arterial infusion chemotherapy and radiofrequency ablation. A right lower lobectomy with lymph node dissection was performed and pathological diagnosis was high-grade fetal adenocarcinoma, stage IV.