Adjuvant endocrine therapies for pre-/perimenopausal women.

Endocrine therapy in the form of ovarian ablation was developed over a century ago. It remains nonetheless one of the most effective and most clearly targeted form of systemic therapy for breast cancer. Endocrine or hormonal therapy has an effect on virtually only those women whose tumors are positive for estrogen receptors (ER) and/or progesterone receptors (PgR). The presence of these steroid hormone receptors remains the most useful predictive factor in selecting therapy for breast cancer.