Cáncer de seno y hormonoterapia. Estado actual

The management of breast cancer is classically interdisciplinary, involving surgery, chemotherapy, and radiotherapy. Hormone therapy is a treatment modality that has been in long use for hormone-sensitive breast cancers. Around 75% of patients exhibit hormone receptors in the tumor; thus, the standard therapy has been the anti-estrogens, principally tamoxifen, an agent that has been in use for more than 25 years with solid evidence of good results; prospective clinical studies have shown good response with improvement in disease-free survival and total survival, both in premenopausal and postmenopausal women. New agents have been developed that are free of the side effects of tamoxifen over the endometrium and the coagulations mechanisms: the aromatase inhibitors, that have demonstrated superiority over tamoxifen in patients with metastatic diseases, as well as in adjuvant therapeutic schemes. The better results are manifested by longer disease-free survivals and freedom of the endometrial and thrombotic side effects. However, their prolonged use may augment the risk of osteoporosis and fractures. The use of aromatase inhibitors remains restricted to postmenopausal women. Premenopausal women require some type of concomitant ovarian blockade. In this paper the authors present a review of the current trends, including both neoajuvant therapy and chemoprevention. It is now considered that every patient with mammary cancer that exhibits any expression of hormonal receptors (more than 1% demonstrated by immunochemistry) will benefit from hormone therapy; tamoxifen given for a period of 5 years is an excellent drug to be used in cases with very good prognosis, but when contraindicated or when there exist risk factors of local or systemic recurrence, postmenopausal women with hormone-sensitive tumors will rather benefit from the use aromatase inhibitors as primary adjuvant therapy or in exchange after 2, 3, or 5 years of tamoxifen. Current evidence indicates that the treatment may be prescribed for more than 5 or 10 years. This article is a review of hormone therapy in breast cancer, from its start many years ago until the current recommendations in the different clinical scenarios.