Estrogen synthesis inhibitors for breast cancer: an introductory overview

Breast cancer is diagnosed in almost one in eight women in the United States and western Europe (Li et al. 1993). Surgical excision, the initial therapy of breast cancer in the majority of women, is often not curative and tumors recur months to years later (Fisher et al. 1993). One-third of these lesions respond to estrogen deprivation with objective regression (Santen et al. 1990). For this reason, much attention has been directed towards the development of therapeutic agents which can effectively block estrogen biosynthesis or antagonize the effects of estrogen at the cellular level (Santen 1993). This issue of Endocrine-Related Cancer reviews the rapid progress and major accomplishments in achieving these goals. To allow insight into the importance of recent results and a vision towards future developments, the findings presented in this issue are best viewed in a broad perspective. This introduction will outline several key concepts regarding the hormonal