Alpha-fetoprotein-producing early gastric cancer: report of two cases.

We have experienced two cases of alpha-fetoprotein (AFP)-producing early gastric cancer. One patient was a 73-year-old man diagnosed as having an early gastric cancer type 0 I + IIa at 40 x 40 mm on the greater curvature of the lower body of the stomach. The histological findings showed that proliferation of a well-differentiated tubular adenocarcinoma with hepatoid pattern was massively invading to the middle layer of the submucosa, with positive lymph vessel, and lymph node metastasis. The other patient was a 76-year-old man diagnosed as having an early gastric cancer type 0 IIa + IIc at 25 x 25 mm on the anterior wall on the greater curvature of the antrum. The histological findings showed that proliferation of a small cell carcinoma was massively invading to the deep layer of the submucosa, with positive lymph vessel, and lymph node metastasis. AFP was immunohistochemically found in the tumor cells of these two cases. Both patients died from liver metastasis. AFP-producing early gastric cancer was concluded to be at high risk of liver metastasis.