Taxane-Based Combinations As Adjuvant Chemotherapy of Early Breast Cancer: A Meta-Analysis of Randomized Trials

PURPOSE: We conducted a meta-analysis of randomized trials that evaluated the efficacy of incorporating taxanes into anthracycline-based regimens for early breast cancer (EBC). We aimed to determine whether this approach improves disease-free survival (DFS) and overall survival (OS) and whether benefits are maintained across relevant patient subgroups. METHODS: Studies were retrieved by searching the PubMed database and the proceedings of major conferences. We extracted hazard ratios (HR) and 95\% CIs for DFS and OS from each trial and obtained pooled estimates using an inverse-variance model. RESULTS: Thirteen studies were included in the meta-analysis (N = 22,903 patients). The pooled HR estimate was 0.83 (95\% CI, 0.79 to 0.87; P < .00001) for DFS and 0.85 (95\% CI, 0.79 to 0.91; P < .00001) for OS. Risk reduction was not influenced by the type of taxane, by estrogen receptor (ER) expression, by the number of axillary metastases (N1 to 3 v N4+), or by the patient's age/menopausal status. Sensitivity analysis showed that taxanes given in combination with anthracyclines, unlike sequential administration, did not significantly improve OS. However, the test for interaction showed that HR did not differ between the two schedules (P = .54). Taxane administration resulted in an absolute 5-year risk reduction of 5\% for DFS and 3\% for OS. CONCLUSION: The addition of a taxane to an anthracycline-based regimen improves the DFS and OS of high-risk EBC patients. The DFS benefit was independent of ER expression, degree of nodal involvement, type of taxane, age/menopausal status of patient, and administration schedule.