Changes in immunoexpression of E-cadherin and beta-catenin in oral squamous cell carcinoma with and without nodal metastasis.

The aim of this study is to analyze the immunohistochemical expression of E-cadherin and beta-catenin in oral squamous cell carcinoma to better understand the biological behavior of this lesion. The sample consisted of 15 cases of the tongue and 15 of the lower lip. The pattern and intensity of the labeling and the analysis of the percentage of tumor cells immunopositive in membrane for E-cadherin and beta-catenin were related to the anatomic location of the lesion, the presence or absence of nodal metastasis, and the histological gradation of malignancy in the tumor invasion front. The presence or absence of cytoplasmic and nuclear labeling was also recorded. The membrane expression for E-cadherin and beta-catenin predominately displayed a heterogeneous pattern in the carcinomas studied. No significant difference was observed between the expression pattern and the quantity of cells immunopositive for E-cadherin and beta-catenin and the anatomic location of the lesion or the presence or absence of nodal metastasis. However, a statistically significant difference was found between the reduced expressio\n of these proteins and the high malignancy score. The reduced immunoexpression of these proteins in the membrane may be related to the high degree of cell indifferentiation in cases of oral squamous cell carcinoma with high scores.