Background : Recent advances in immunohistochemical staining have led to the proposition of a classification of gastric carcinomas based on cellular phenotypes, and the degree of biological malignancy of gastric-phenotype carcinomas has attracted particular attention.
Subjects and Methods : One hundred and seven submucosal (SM) invasive carcinomas encountered in our center were examined for their histological type, cellular phenotype, and E-cadherin expression status to clarify their relationships with lymph node metastasis.
Results : Eleven (10.3%) of 107 SM gastric carcinomas were lymph node metastasis-positive. Gastric-phenotype carcinomas accounted for 20.6%, with a lymph node metastasis rate of 27.3% (6/22), which was significantly higher (p<0.05) than those of intestinal-phenotype carcinomas (5.9%) and mixed-phenotype carcinomas (2.9%). In terms of E-cadherin expression, only carcinomas with reduced E-cadherin expression showed lymph node metastasis at a rate significantly higher than that of carcinomas with normal E-cadherin expression (p<0.05). The lymph node metastasis rate (46.2%) of gastric-phenotype carcinomas with reduced E-cadherin expression was significantly higher than those of carcinomas of other phenotypes (p<0.05).
Conclusion : Since gastric-phenotype differentiated carcinomas with reduced E-cadherin expression have the potential for becoming undifferentiated, the risk of lymph node metastasis should be considered