Second-Line Endocrine Treatment of Advanced Breast Cancer—A Randomized Cross-Over Study of Medroxy-Progesterone Acetate and Aminoglutethimide

Treatment of advanced breast cancer is palliative and care should be taken not to introduce undue toxicity. Most postmenopausal women are primarily treated with tamoxifen. Those responding favorably are often treated with second- and third-line endocrine therapy upon progression on the previous modality. Currently, progestins and aromatase inhibitors are used for this purpose. These two classes of drugs have characteristic side effects, but seemingly similar response rates and no preference for the one or the other has been concluded so far (Canney et al. 1988, Lundgren et al. 1989, Samonis et al. 1994).