Malignant insulinoma with hepatoid differentiation: a unique case with alpha-fetoprotein production.

Hepatoid carcinomas are uncommon extra-hepatic neoplasms exhibiting features of hepatocellular carcinoma and they are most frequently described in the stomach. We report a 64-year-old woman with a malignant insulinoma showing focal hepatoid differentiation and biochemical evidence of alpha-fetoprotein (AFP) production. The current case is the first malignant insulinoma with hepatoid differentiation. Resection of the primary tumor followed by regional embolization was peformed. The patient died 22 months after initial presentation. Thus, the presence of hepatoid differentiation in pancreatic tumor should be noted as the tumor may be associated with elevated AFP. The features of pancreatic hepatoid carcinomas are discussed.