[Endoscopic ultrasonography for assessing the horizontal spread of invasive gastric cancer].

The subjects were 64 cases of gastric cancer. In all 64 cases, resected specimens (formalin fixed) were subjected to endoscopic ultrasonographic examination by the water immersion method in order to assess the horizontal spread of the invasive gastric cancer. Ultrasonographic findings were compared with the histopathological findings of resected specimens. The tumor which invaded the submucosa or deeper layers was visualized as low echogenicity region in the third layer (corresponding to the submucosa) or deeper layers. The horizontal spread of the low echogenicity region represented that of the tumor or the associated fibrosis, but not the tumor itself. In the cases showing echo patterns which were characteristic of the peptic ulceration in the tumor focus (Type II-1, II-2, UL), the horizontal spread of cancer invasion in the submucosal layer or deeper layers (L Ca) was smaller than that of low echogenicity region depicted by ultrasonography (L U). In the other (Type II-3, III, A, B) cases, L Ca was almost comparable to L U.