Cross-over comparison of tamoxifen and aminoglutethimide in advanced breast cancer.

Thirty-four postmenopausal patients with advanced breast cancer had an overall objective response rate of 47% when treated with aminoglutethimide and hydrocortisone initially and a response rate of 24% when crossed over to therapy with tamoxifen after progression on aminoglutethimide. A similar group of 32 patients experienced a response rate of 28% when treated with tamoxifen first and a 19% objective response rate on subsequent therapy with aminoglutethimide. Patients who failed to respond to the first therapy seldom responded on cross-over to the alternate therapy. Toxicities were acceptable with both forms of therapy. Tamoxifen and aminoglutethimide used sequentially are effective forms of palliative hormonal therapy in metastatic breast cancer.