Early gastric cancer of adenosquamous carcinoma type: report of a case and review of literature.

We report a case of adenosquamous carcinoma of the stomach which involved only the mucosa and submucosa, but was found to have already metastasized to a regional lymph node and the liver at surgery. Adenosquamous carcinomas of the stomach are rare and usually invade deeply into the muscular layer. Those limited to the mucosa and submucosa are extremely rare, and only seven cases have been reported to date. It was interesting that in our case, 80% of the tumor in the stomach and lymph node was composed of squamous cell carcinoma and 20% consisted of adenocarcinoma, whereas the metastases in the liver consisted entirely of adenocarcinoma. The literature on this type of gastric carcinoma is reviewed and the possible histogenesis of this tumor is discussed.