RESUMO
Efficacy and safety of toremifene 60 and 240 mg daily (TOR 60 and TOR 240) are compared to 40 mg tamoxifen daily (NFV 40) in postmenopausal women with advanced estrogen receptor (ER) positive of ER unknown breast cancer. The study is randomized in three parallel groups. Primary efficacy variables are response rate and time to progression. WHO and ECOG criteria were used for measurable and nonmeasurable disease assessment, respectively. Safely was reported according to WHO criretia. Altogether 463 patients were randomized (157 to TOR 60, 157 to TOR 240 and 149 to TAM 40). By data cut-off, after 20.5 months medianfollow-up time, over 70% of the patients had experienced disease progression. Response rates are 20.4%, 28.7% in TOR 60, TOR 240 and TAM 40, respectively. TOR 60 and TAM 40 show statistically equivalent efficacy and the difference between TOR 240 and TAM 40 is not significant (P = 0.112). Median times to progression are 4.9 (TOR 60), 6.1 (TOR 240) and 5.0 (TAM 40) months and corresponding hazard ratios (TAM:TOR) 1.015 and 1.124. Again, TOR 60 and TAM 40 are statistically equivalent and the difference between TOR 240 and TAM 40 is not significant (P = 0.374). All treatments were well tolerated. As a conclusion TOR 60 and TAM 40 show equivalent clinical efficacy and tolerability. The higher dose of toremifene slightly but not significantly improved response rate and time to progression. In postmenopausal women, toremifene (60 mg) daily is an effective and safe treatment of advanced ER positive or ER unknown breast cancer.