Is it liver or lung cancer? An intriguing case of lung adenocarcinoma with hepatoid differentiation

Abstract

We report the case of a 50-year-old man who was investigated for an incidental finding of a left lung mass following left shoulder pain over a three month period. He also had a significant raised serum alpha-fetoprotein (AFP) level of 29,000, which raised the suspicion of hepatocellular carcinoma with lung metastases. However, there was no detectable liver lesion on multiphase contrasted tomography of the liver and no significant hypermetabolic nodes or distant metastasis seen in the liver on positron emission tomography scan. A lung biopsy confirmed adenocarcinoma with hepatocellular differentiation that would explain the raised serum AFP level.