[A case of hepatoid adenocarcinoma of the stomach]

The patient was a 76-year-old man with no chief complaint. He presented to an internist of our hospital for an evaluation of anemia. An upper gastrointestinal endoscopy revealed a type 2 tumor at the lesser curvature of the gastric body. Although the blood analysis showed a high amount of AFP(2, 328 ng/mL), there was no abnormality found in the liver with a CT scan. The tumor was presumed to be an AFP-producing gastric cancer on the basis of the tumor biopsy. We performed total gastrectomy, splenectomy and cholecystectomy. The tumor cells were positive for AFP by immunohistochemistry. The final diagnosis was hepatoid adenocarcinoma, pT3(SS), INF b, ly1, v2, pN1(3/42), pStage II B. Tumor cells were negative for antihepatocyte antibody and anti-HER2 antibody. The amount of AFP normalized postoperatively. After discharge, he was treated with S-1(80mg/day)orally. He is relapse-free now, 14 months after the operation. Hepatoid adenocarcinoma is an extremely aggressive tumor with a poor prognosis, and effective chemotherapy has still not been established. A larger number of analyses, along with a molecular biological approach, is sure to be helpful for the establishment of an effective treatment for hepatoid adenocarcinoma.