toremifene and zindoxifene

During recent years the development of hormone therapy for the treatment breast neoplasms has seen, in addition to classic aspecific antiestrogens (AE) like tamoxifen (TAM) and to a lesser extent toremifen, a major development of new molecules divided into two groups: the first is the so-called selective estrogen receptor modulators (SERMs), the most important of which is Raloxifen, which mediate estrogen-agonist effects in some tissues and estrogen-antagonist effects in others; the second group includes the aromatase inhibitors (AI), important enzymes for peripheral estrogen conversion. Some studies compare or associate classic AE with the new SERMs and AI, both in adjuvant therapy and in treatment for advanced forms. Other trials assess the anti-osteoporotic activity of some SERMs which present concomitant inhibitory activity on the breast and endometrium.

Topics: Adult; Anastrozole; Antineoplastic Agents; Antineoplastic Agents, Hormonal; Aromatase Inhibitors; Breast Neoplasms; Clinical Trials as Topic; Clinical Trials, Phase III as Topic; Enzyme Inhibitors; Estrogen Antagonists; Female; Forecasting; Humans; Indoles; Letrozole; Middle Aged; Neoplasm Metastasis; Nitriles; Osteoporosis; Postmenopause; Raloxifene Hydrochloride; Selective Estrogen Receptor Modulators; Tamoxifen; Toremifene; Triazoles

The antiestrogen tamoxifen has had an enormous impact upon the therapy of breast cancer. It is the most widely used antihormonal therapy. The success of tamoxifen has stimulated broader applications of the drug (long-term adjuvant therapy and chemosuppression) and has spurred the development of toremifene, droloxifene, and zindoxifene. However, the clinical evaluation of tamoxifen as a chemosuppressive agent is not sufficiently advanced to be able to provide any conclusion about the success of this strategy. It may be a decade before a randomized clinical study can be analyzed and the value of chemosuppression assessed. In the near future, the clinical evaluation of new antiestrogens will provide additional information about the potential value of these drugs and will perhaps challenge our ideas about the mode of action of antiestrogens as antitumor agents.

Topics: Breast Neoplasms; Estrogen Antagonists; Female; Humans; Indoles; Tamoxifen; Toremifene