O-acetyl sialomucin and differentiation of stomach cancer: a histochemical study.

In one hundred surgical specimens with stomach cancer, 78 cases contained intestinal metaplasia (IM) in the outer margin mucosa nearby carcinoma focus, while the remaining 22 had no IM. IM was histochemically classified into small intestinal type, sulphomucin colonic type (S), O-acetyl sialo-sulphomucin colonic type (OS) and O-acetyl sialomucin colonic type (O). The incidence of OS and O in well differentiated carcinoma (WCa) (22/27) was obviously higher than in poorly and undifferentiated carcinomas (PUCa) (17/51) (X2 = 14.5011, P less than 0.001). This suggests that O-acetyl sialomucin in IM may be correlated with the differentiation of gastric cancer, that is, OS may often be transformed into WCa if malignant change of IM occurs.