Histopathological and Immunohistochemical Study of E-cadherin in Breast Neoplasia

Immunohistochemical staining was undertaken for E-cadherin (EC), estrogen and progesterone receptors; on tissue sections of normal breast, proliferative breast lesions and malignant breast lesions. The EC positive expression manifested itself as sharp membranous staining and was assessed semi-quantitative into four categories: 0; 1+ were considered negative immunoreactivity, while 2+ and 3+ were scored as positive immunoreactivity. Although 95% of non malignant proliferative breast lesions showed positive EC immunoreactivity and reduced or lost EC expression in all Pre-invasive cases. None of invasive lobular cases express EC, in contrast to 30% of invasive duct carcinoma cases, showed reduced or lost EC expression in high histological grades. Correlation between the EC staining intensity and IDC, ILC and TC groups, statistical analysis was highly significant only for TC (p< 0.001). There was a significant relationship between E-cadherin expression and different breast neoplastic histological types. The molecular signature of breast lobular carcinomas is the loss of E-cadherin protein expression as evidenced by immunohistochemistry, whereas ductal carcinomas are typically E-cadherin positive. Present study suggests that E-cadherin may be involved in the pathogenesis of this form of breast cancer.