The use of fulvestrant before chemotherapy improves survival in hormone-positive breast cancer: a real-life study

Background/aim: We aimed to evaluate the efficacy of fulvestrant and its affecting clinical factors, including the optimal sequencing of fulvestrant and chemotherapy in a real-life cohort. Methods: The data of 256 metastatic hormone-positive breast cancer patients treated with fulvestrant were evaluated. The association of clinical factors with survival was analyzed with Kaplan-Meier and Cox-regression analyses. Results: The median age of patients was 57 years. More than half of the patients used fulvestrant in later lines and after chemotherapy (75.8%). The median progression-free (PFS) and overall survival (OS) of all cohort were 6.05 +/- 0.56 and 29.70 +/- 1.61 months, respectively. Primary endocrine resistance (HR: 1.989, 95% CI: 1.430-2.766, <0.001), use of fulvestrant after chemotherapy (HR: 1.849, 95% CI: 1.182-2.891, p = 0.007) and visceral metastases (HR: 1.587, 95% CI: 1.128-2.233, p = 0.008) were associated with decreased OS in multivariate analyses. Sixteen patients were treated with trastuzumab and fulvestrant combination. The overall response rate (p = 0.340), disease control rate (p = 0.076), and OS (p = 0.289) and PFS (p = 0.276) were similar to overall cohort. Conclusion: In our experience, fulvestrant treatment was associated with comparable OS to clinical trials in a large cohort of patients. Patients treated with fulvestrant before chemotherapy were garnered significantly more benefit.