[Risk of breast cancer of low differentiation in tumors with estrogen-negative receptors].

The risk for poorly differentiated invasive ductal carcinoma was evaluated in negative estrogen receptor tumors determined by immunohistochemical method. The results were correlated with the histological grade. The poorly differentiated tumors had a major risk (OR = 17.8) to be negative. A high risk of correlation was found between the estrogen receptor positivity and the well differentiated tumors (grade I), p = .0001. Our results are similar to other previous reports. The usefulness of this findings and its occasional role when it was not possible the determination of this receptor for lacking economical or technological resources is discussed.