Hepatoid Adenocarcinoma of the Lung: A Case Report and Review of the Literature

Abstract

Hepatoid adenocarcinoma (HAC) is a rare type of extrahepatic cancer, with pathologic features largely indistinguishable from hepatocellular carcinoma. Thirty cases of HAC have been described. The majority of HAC cases arise in the lung. Extrapulmonary HAC occurs in the stomach [1], and cases have been reported in the mediastinum, esophagus, gallbladder, pancreas, ampulla of Vater, renal pelvis, bladder, endometrium, ovary, and testicle [2–5]. In addition to the pathologic similarities to hepatocellular cancer, a large proportion of HACs produce AFP, and plasma levels may be very high [6]. Alpha-fetoprotein (AFP) was first detected in the serum of a patient with a primary liver tumor in 1965 [7] and has since been used as a tumor indicator for either primary liver or yolk sac tumors [8,9]. Certain gastrointestinal tumors such as gastric, rectal, and pancreatic carcinomas as well as lung cancer also secrete AFP [10–12]. We are reporting the second female case of pulmonary HAC who presented with elevated AFP and was treated with lobectomy and 3 cycles of adjuvant platinum-doublet chemotherapy. Case Presentation