OBJECTIVEThis study was to clarify E-cadherin expressions in non-small cell lung cancer (NSCLC) and its correlation with patients' prognosis.

METHODSTissue microarrays (TMAs) containing specimens from 365 different NSCLC were constructed, covering all stages and almost all histological types of this disease. Slides were immunohistochemically stained with antibodies against E-cadherin. Expression pattern of the protein was analyzed with relation to the clinicopathological. Correlations of the results with patients' overall survival were also examined.

RESULTSImmunohistochemical staining revealed that E-cadherin protein was localized mainly on membranes and the cytoplasm of NSCLC tumors cells. Reduced E-cadherin expression was evident in 32.1%. Reduced E-cadherin expression significantly correlated with lymph nodes metastasis (chi(2) = 16.430, P = 0.001), histological dedifferentiation (chi(2) = 9.243, P = 0.010) and advanced clinical stage (chi(2) = 9.421, P = 0.024). There was no significant difference in E-cadherin expression between squamous cell carcinoma and adenocarcinoma. E-cadherin reduced expression correlated with a poor prognosis (P < 0.0001) in univariate analysis. Multivariate analysis showed a significantly lower survival probability for patients with reduced E-cadherin (P < 0.001), and E-cadherin was an independent prognostic factor for survival of NSCLC patients.

CONCLUSIONSIt suggests that dysfunction of E-cadherin has an important impact in the progression of lung cancer. As an independent prognostic factor, expression of E-cadherin can predict outcome of different group, together with conventional prognostic factors, and subsequently make appropriate management.