Mean Nuclear Area and Metallothionein Expression in Ductal Breast Tumors: Correlation With Estrogen Receptor Status

Abstract

Breast carcinoma is the most common malignancy in women. Estrogen is an important growth factor for breast tumor that plays an important role in regulating the proliferation and differentiation of normal and malignant mammary epithelial cells. Nuclear morphometry and metallothioneins (MTs) are indicators of proliferation that have been used as predictors of prognosis in many tumors. The present study aimed to study mean nuclear area (MNA) and MT; estrogen receptor (ER) expression in fibroadenoma (FA), ductal carcinoma in situ (DCIS), and infiltrating ductal carcinoma (IDC) of the breast. Also MNA and MT expression will be correlated with histologic grade and ER status in breast carcinoma. Breast tissues from 18 patients with FA, 10 patients with DCIS, and 40 patients with IDC were used in this study. MNA and MT expression; as proliferation markers; were investigated and correlated with ER status. All cases of FA, 7 out of 10 cases (70%) of DCIS and 23 out of 40 cases (57.5%) of IDC were positive for ER. MNA of cancer cells was significantly larger than that of normal and benign breast tissue. A significant direct correlation was found between MNA and histologic grades. MNA of ER-negative carcinomas was significantly larger than that of ER-positive tumors. In normal and benign breast tissue, myoepithelial cells consistently expressed the MT protein. Four out of 10 DCIS cases (40%) and 24 out of 40 cases of IDC cases (60%) were positively stained for MT. MT positivity was directly correlated with histologic grade of IDC. There was a highly significant inverse correlation between MT and ER overexpression. From this study, it is concluded that in invasive ductal carcinoma of the breast, the large MNA and MT overexpression are correlated with histologic grades and ER negativity. Therefore, large MNA and MT overexpression may be possible important indicators for more aggressive and less differentiated breast carcinoma.