Pancreatic carcinoma: correlation between E-cadherin and alpha-catenin expression status and liver metastasis.

Dysfunction of the E-cadherin/catenin-mediated cell-cell adhesion system has been associated with invasiveness and poor differentiation of human carcinomas. However, its importance in the genesis of liver metastasis has not been examined sufficiently. A series of 26 primary pancreatic carcinomas and the concomitant liver metastases from 15 of them, obtained at autopsy, were analyzed for E-cadherin and alpha-catenin protein expression by immunohistochemistry. Both E-cadherin and alpha-catenin expression were preserved in 15 (58%) and reduced in 11 (32%) of the 26 primary pancreatic carcinomas. In the former 15 primaries, carcinoma cells were attached to each other tightly, whereas the latter 11 primaries showed isolated or loosely connected attachments. The metastatic ratio was higher in tumors exhibiting tight adhesion than in those with loose adhesion: 73% and 36%, respectively (P = 0.059). E-cadherin and alpha-catenin expression patterns in liver metastases basically followed those in the corresponding primaries (P < 0.01). Reduced E-cadherin and alpha-catenin expression in primary pancreatic carcinoma has no significant predictive value regarding the presence of liver metastasis. Rather, there is a greater tendency for liver metastasis in cases in which the integrity of the E-cadherin/catenin-mediated cell-cell adhesion system is intact.