Ductal breast tumours: mean nuclear area and metallothionein expression in correlation with estrogen receptor status

ABSTRACT

Estrogen is an important growth Ilictor for breast tumour playing 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 tumours. The present study aimed to study mean nuclear area and MT; ER expression in fibroadenoma, ductal carcinoma in situ and infiltrating ductal carcinoma of the breast. Also MNA and MT expression will be correlated with histologic grade and ER status in breast carcinoma. Breast tissues from 12 patients with fibroadenoma [FA], 6 patients with ductal carcinoma in situ [DCIS] and 20 patients with infiltrating durtal carcinoma [IDC] were used in this study. Mean nuclear area [MNA] and metallothionein [MT] expression; as proliferation markers; were investigated and correlated with estrogen receptor [ER] status. All cases of fibroadenoma, 4 out of 6 cases [66.7%] of DCIS and 12 out of 20 cases [60%] 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 tumours. In normal and benign breast tissue, myoepithelial cells consistently expressed the MT protein. Two out of 6 DCIS cases [33.3%] and 13 out of 20 cases of IDC cases [65%] were positively stained for MT. MT positivity was directly correlated with histologic grade of JDC. There was a highly significant inverse correlation between MT and ER over-expression. From this study, it is concluded that in invasive ductal carcinoma of the breast, the large MNA and MT over-expression are correlated with histologic grades and ER negativity. Therefore, MNA and MT overe-expression may be possible important indicators for more aggressive and less differentiated breast carcinoma