The efficacy and safety of toremifene versus tamoxifen in the treatment of perimenopausal and postmenopausal breast cancer: a system assessment
YAN Han;ZHANG Ruixue;LI Qin;YANG Yifan;XIAO Jing;LIU Wenting;CAO Bangwei;Department of Oncology, Beijing Friendship Hospital, Capital Medical University;
Objective: The efficacy and safety of toremifene in adjuvant endocrine therapy for perimenopausal and postmenopausal breast cancer still not very clear, compared with tamoxifen. The purpose of this meta-analysis was to assess the efficacy and side effects of toremifene versus tamoxifen in the treatment of perimenopausal and postmenopausal breast cancer. Methods: Pub Med, EMBASE as well as Web of Science database were searched for relevant RCTs comparing the efficacy and safety of toremifene with tamoxifen. Jadad scale was used to evaluate the quality of the trials. The result of this systems assessment was pooled by Rev Man5.0 software. Fixed effect model or random effect model was chosen depending on the heterogeneity. Overall survival(OS), progression-free survival(PFS), response rate(RR) are evaluated as the outcomes in our analysis. The toxicities included nausea and vomiting, vagina discharge, hot flash, vagina bleeding, ophthalmological and thromboembolic events. Results: Eight randomized trials including 5 734 cases published in the three articles were eligible. OS time to progression(TTP) and 5-year disease-free-survival rates was not significantly different between tamoxifen group and toremifene group(OS: HR=1.00, 95% CI: 0.85~1.16; TTP: HR=0.93, 95% CI: 0.81~1.06; 5-year DFS: OR=1.11, 95% CI: 0.88~1.40. The results meta-analyses showed toremifene significantly increased 5-year overall survival rates compared with tamoxifen(OR=1.26, 95% CI: 1.04~1.53, P=0.02). The incidence of nausea and vomiting, hot flash and vagina bleeding between the two groups were similar. The incidence of the ophthalmological(OR: 0.63, 95% CI: 0.46~0.85, P=0.003) and thromboembolic(OR: 0.69, 95% CI: 0.54~0.90, P=0.006) events in the toremifene group were higher compared with the tamoxifen group. The incidence of vagina discharge was higher in toremifene group(OR: 1.30, 95% CI: 1.04~1.63, P=0.02). Conclusion: The efficacy and safety of toremifene is similar to tamoxifen in the treatment of perimenopausal and postmenopausal breast cancer. The long-term prognosis of toremifene may be better than tamoxifen.