[Alpha Fetoprotein-producing Lung Adenocarcinoma].

We report a case of alpha fetoprotein (AFP) -producing lung adenocarcinoma. A 53-year-old man was referred to our hospital due to right pneumothorax. Computed tomography showed right moderate pneumothorax, a solid tumor in the upper lobe (S3) and mediastinal lymph node swelling. The serum AFP level was as high as 223.0 ng/ml. Frozen examination revealed a low-differentiated adenocarcinoma. Based on the pathological and immunohistochemical findings, the tumor was diagnosed as AFP-producing lung adenocarcinoma.