Comparison of Biological Behavior of Differentiated Type Gastric Adenocarcinoma by Their Cytological Grade of Atypia : From the Aspect of Invasive Capacity and Cell-Proliferative Activity

Differentiated type gastric adenocarcinomas are subclassified into high-grade and low-grade by their cytological atypia. We aimed to clarify the difference in biological behavior (grade of malignancy) of high-grade and low-grade carcinomas in the aspect of invasive capacity and cell-proliferative activity. Forty-six high-grade and fifteen low-grade gastric submucosal carcinomas (well or moderately differentiated) were selected for the study. High-grade carcinoma showed smaller (trend) intramucosal spread while greater (P<0.01) area of submucosal invasion and its proportion to the intramucosal spread than low-grade carcinoma. Cell-proliferative activity was estimated by Ki-67 labeling index. For both intramucosal and submucosal area, high-grade carcinoma showed higher (P