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

Reduced expression of E-cadherin (E-cad), a transmembrane glycoprotein, is associated with loss of differentiation, acquisition of an inversive phenot ype, 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 clinico pathologic parameters and patient survival. Absent or low E-cad expression was observed more frequently in solid than in cribriform or tubular carcino mas. E-cad expression also was significantly correlated with histologic gra de and the growth pattern. In addition, ACCs showing low or absent E-cad ex pression were more frequently larger than 4 cm in diameter and distant meta stases developed more frequently. Reduced expression correlated with shorte r disease-free intervals and actuarial survival rates. Univariate and multi variate analysis identified tumor stage and E-cad expression as the only 2 parameters predictive of the disease-free interval. E-cad expression and tu mor 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 analysi s. These findings indicate that the loss off-cad has an important role in t he natural history of ACC, as it is associated with loss of differentiation and development of metastases. We also provide evidence that E-cad express ion is an independent indicator of clinical aggressiveness in patients with ACC, together with clinical stage and type of growth at the periphery of t he tumor.