[Mucin histochemical study of differentiated adenocarcinoma of stomach]

The mucin phenotypic expression of gastric differentiated adenocarcinoma was investigated by mucin histochemical method. Seventy-nine advanced gastric carcinomas, which showed histologically differentiated type (well and moderately differentiated type) in the mucosa, were classified into four types; gastric type (30.4%), intestinal type (19.0%), combined type with both gastric and intestinal phenotype (45.6%) and lack of mucin type (5.1%). Moreover, differentiated adenocarcinoma of gastric type were subclassified into foveolar (F) type (37.5%), pyloric gland (P) type (37.5%) and mixed (M) type with foveolar and pyloric type (25.0%). Both gastric type and intestinal type differentiated adenocarcinoma were apt to change to undifferentiated type in the invasive lesion below the submucosa. On the contrary, carcinoma of combined type changed to undifferentiated type with significantly lower incidence than the former two type. F-type differentiated adenocarcinoma tended to develop scirrhous or non-solid type infiltration and carcinoma of P-type showed medullary or solid growth with significantly higher incidence than the other type. Mucin phenotypic expressions of differentiated adenocarcinoma had much to do with the mode of growth and infiltration of cancer in the gastric wall below the submucosal layer.