Gastric and intestinal phenotypic marker expression in gastric carcinomas and its prognostic significance: immunohistochemical analysis of 136 lesions

OBJECTIVE: It is well known that both gastric and intestinal phenotypic cell markers are expressed in gastric carcinomas, irrespective of their histologic type. However, the clinicopathologic significance of these expressions has not yet been clarified. METHODS: We analyzed the correlations among gastric and intestinal phenotypic marker expression patterns of the tumor, clinicopathologic findings and the patient's outcome in 136 advanced gastric carcinomas. RESULTS: Phenotypic marker expression was immunohistochemically evaluated using the monoclonal antibodies 45M1 (anti-human gastric mucin; HGM), CLH5 (anti-MUC6), Ccp58 (anti-MUC2) and 56C6 (anti-CD10). All tumors were classified as gastric (G), gastric and intestinal mixed (GI), intestinal (I) or unclassified (UC) phenotype. Of the 136 gastric carcinomas, 50 (36.8%), 56 (41.2%), 21 (15.4%) and 9 (6.6%) were classified as G, GI, I and UC phenotype, respectively. The G-phenotype tumors were associated with a higher rate of undifferentiated-type and infiltrative histology as compared with the I-phenotype tumors (p < 0.05 and p < 0.001, respectively). Furthermore, both univariate and multivariate analysis of survival revealed the G-phenotype tumor to be associated with a significantly poorer outcome than the I-phenotype tumor (p < 0.05). CONCLUSION: Our present results indicate that the gastric and intestinal phenotypic marker expression pattern of tumors, determined by the combination of HGM, MUC6, MUC2 and CD10 expression, is prognostically useful for patients with gastric carcinoma.