Benefit of taxanes as adjuvant chemotherapy for early breast cancer: pooled analysis of 15,500 patients

Abstract

Background: The magnitude of the survival benefit of taxanes as adjuvant chemotherapy for early breast cancer is still unclear. A pooled analysis of Phase III trials was performed to assess the advantages that adjuvant taxane chemotherapy has over standard chemotherapy.

Methods: All Phase III trials were considered eligible. A pooled analysis was accomplished and event-based relative risk ratios (RR) with 95% confidence intervals (95% CI) were derived. The significant differences in disease-free survival (DFS) and overall survival (OS) were explored. Magnitude outcome measures were absolute benefits and the number of patients needed to treat. A heterogeneity test was applied as well. A sensitivity analysis in 6 subpopulations was also performed.

Results: Nine trials designed to assess if paclitaxel or docetaxel improve survival (15,598 patients) were gathered. One of the 9 trials did not report OS results. Significant differences in favor of taxanes were seen in DFS in the overall (RR: 0.86; 95% CI, 0.81-0.90 [P<.00001]) and lymph node-positive population (RR: 0.84; 95% CI, 0.79-0.89 [P<.0001]), and in OS in the overall (RR: 0.87; 95% CI, 0.81-0.83 [P<.0001]) and lymph node-positive population (RR: 0.84; 95% CI, 0.77-0.92 [P<.0001]). The absolute benefits in DFS and OS in favor of taxanes ranged from 3.3% to 4.6% and from 2.0% to 2.8%, respectively.

Conclusions: Considering all the available Phase III trials, taxane-based adjuvant chemotherapy for early breast cancer seems to add a significant benefit in both DFS and OS over standard chemotherapy. The lack of significant heterogeneity in the sensitivity analysis underscores the homogeneous effect across all trials.

Copyright (c) 2006 American Cancer Society.