Principles and indications of endocrine treatment of advanced breast cancer.

The numerous trials that have been conducted in advanced breast cancer in premenopausal and postmenopausal women have increased the empiric basis for systemic cytotoxic and endocrine treatment. The treatment results have improved but are still very unsatisfactory, and with all the drugs now at our disposal many questions are still unanswered. For instant this applies to the optimal composition and scheduling of endocrine treatment, cytotoxic treatment, and combinations of these two treatments. During recent years the results of experimental studies have expanded our knowledge of the biology of breast cancer. Future clinical trials should be designed to test and use this information gained from basic research with the aim of improving the rational basis of treatment and obtaining better treatment results in advanced breast cancer.