Successful resection of alpha-fetoprotein-producing lung cancer.

We present a case of successfully resected alpha-fetoprotein (AFP)-producing primary lung cancer. AFP in the serum decreased from 289 ng/ml to an undetectable level after a curative operation. The resected tumor was stained positively by the immunohistochemical study for AFP. The histologic appearance of the tumor was well-differentiated adenocarcinoma similar to that of fetal gut epithelium and apparently different from extragonadal germ cell tumor. This case provides evidence that lung cancer cells possess the potential to produce AFP.