Carcinoma at the esophago-gastric junction--its biological behaviour toward the squamous epithelium.

The purpose of this paper is to assess the clinical and histopathological significance of tumors at the esophago-gastric junction (EGJ). The biological behaviour of these tumors was studied, with regard to the infiltrative pattern and mitotic index, in 15 patients with tumors at the EGJ. Twenty-seven tumors at the cardia, with or without esophageal invasion, were chosen for DNA analysis at their most proximal and deepest apexes. The esophageal and gastric apexes of the tumors had the same infiltrative pattern in 14 out of 15 cases and this tendency was not altered with further stratification of the anatomical layers. In comparing the deviations of the stem lines, the relative frequency of nuclei with DNA over 4n and 6n and aneuploid from the DNA histograms between the esophageal and the deepest apexes of the tumor revealed no statistically significant differences, depending on esophageal invasion. From these results, the specificities of EGJ toward tumor invasion or activity were not regarded as consequential, and the EGJ couldn't be regarded as a barrier against tumor invasion.