Toremifene, a new antiestrogenic compound in the treatment of metastatic mammary cancer. A phase II study.

Toremifene is a new antiestrogenic compound. Toremifene has definite antitumor effect in advanced breast cancer. The response rate in the present phase II study among postmenopausal women, mostly not pretreated with systemic therapy and with ER positive or not determined ER status in tumor tissue, was 11/23 (48%; 95% confidence interval 37-59%) including 6 complete responses. The toxicity profile was similar to that of tamoxifen. It is concluded that toremifene is at least as active as tamoxifen in advanced breast cancer and that a randomized study between these two antiestrogens is indicated.