[Adenosquamous carcinoma of the stomach].
Adenosquamous carcinoma (ASC) of the stomach is a rare tumour. In this report we present a case of adenosquamous carcinoma in the antrum involving the duodenal bulb in a 84 year old woman. Although several theories about the possible origin of this kind of tumours had been proposed, histological and immunohistochemical findings agree with the possibility of a preexisting adenocarcinoma as the most reliable cause. The prognosis of ASC seems worse than that of adenocarcinoma because of the more extensive tumour depth and higher frequency of lymphatic and vascular permeation of the carcinomas cells when it is discovered.