Reduced E-cadherin expression correlates with unfavorable prognosis in adenoid cystic carcinoma of salivary glands of the oral cavity.

Abstract

Reduced expression of E-cadherin (E-cad), a transmembrane glycoprotein, is associated with loss of differentiation, acquisition of an invasive phenotype, and an unfavorable prognosis in carcinomas from several sites. We used immunohistochemistry to study the expression of E-cad in 50 adenoid cystic carcinomas (ACCs) in salivary glands to evaluate correlations with clinicopathologic parameters and patient survival. Absent or low E-cad expression was observed more frequently in solid than in cribriform or tubular carcinomas. E-cad expression also was significantly correlated with histologic grade and the growth pattern. In addition, ACCs showing low or absent E-cad expression were more frequently larger than 4 cm in diameter, and distant metastases developed more frequently. Reduced expression correlated with shorter disease-free intervals and actuarial survival rates. Univariate and multivariate analysis identified tumor stage and E-cad expression as the only 2 parameters predictive of the disease-free interval. E-cad expression and tumor stage, grade, and type of growth were significant prognostic factors for survival in univariate analysis, while tumor stage, type of growth, and E-cad expression were the only significant covariates in multivariate analysis. These findings indicate that the loss of E-cad has an important role in the natural history of ACC, as it is associated with loss of differentiation and development of metastases. We also provide evidence that E-cad expression is an independent indicator of clinical aggressiveness in patients with ACC, together with clinical stage and type of growth at the periphery of the tumor.