Exogenous hormone use and fibrocystic breast disease by histopathologic component.

In a hospital-based case-control study of 590 women with biopsy-proven fibrocystic breast disease and 1,018 control women with other surgical conditions, no linear relationship was evident between the use of oral contraceptives or of estrogen replacement therapy and the degree of epithelial atypia of the fibrocystic lesions. Case-control and intracase comparisons suggested that oral contraceptive use might be associated with an increased occurrence of sclerosing adenosis among the premenopausal women and of gross cysts among the postmenopausal women. Estrogen replacement therapy, which was positively associated with fibrocystic breast disease as a whole among the post-menopausal women, was most frequently used among the cases whose biopsy specimens exhibited gross cysts, papillomatosis or papillary hyperplasia.