Fulvestrant for hormone‐sensitive metastatic breast cancer

Background Fulvestrant is a selective oestrogen receptor down‐regulator (SERD), which by blocking proliferation of breast cancer cells, is an effective endocrine treatment for women with hormone‐sensitive advanced breast cancer. The goal of such systemic therapy in this setting is to reduce symptoms, improve quality of life, and increase survival time. Objectives To assess the efficacy and safety of fulvestrant for hormone‐sensitive locally advanced or metastatic breast cancer in postmenopausal women, as compared to other standard endocrine agents. Search methods We searched the Cochrane Breast Cancer Specialised Register, the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, the World Health Organization International Clinical Trials Registry Platform (WHO ICTRP), and ClinicalTrials.gov on 7 July 2015. We also searched major conference proceedings (American Society of Clinical Oncology (ASCO) and San Antonio Breast Cancer Symposium) and practice guidelines from major oncology groups (ASCO, European Society for Medical Oncology (ESMO), National Comprehensive Cancer Network, and Cancer Care Ontario). We handsearched reference lists from relevant studies. Selection criteria We included for analyses randomised controlled trials that enrolled postmenopausal women with hormone‐sensitive advanced breast cancer (TNM classifications: stages IIIA, IIIB, and IIIC) or metastatic breast cancer (TNM classification: stage IV) with an intervention group treated with fulvestrant with or without other standard anticancer therapy. Data collection and analysis Two review authors independently extracted data from trials identified in the searches, conducted 'Risk of bias' assessments of the included studies, and assessed the overall quality of the evidence using the GRADE approach. Outcome data extracted from these trials for our analyses and review included progression‐free survival (PFS) or time to progression (TTP) or time to treatment failure, overall survival, clinical benefit rate, toxicity, and quality of life. We used the fixed‐effect model for meta‐analysis where possible. Main results We included nine studies randomising 4514 women for meta‐analysis and review. Overall results for the primary endpoint of PFS indicated that women receiving fulvestrant did at least as well as the control groups (hazard ratio (HR) 0.95, 95% confidence interval (CI) 0.89 to 1.02; P = 0.18, I2= 56%, 4258 women, 9 studies, high‐quality evidence). In the one high‐q