Does Timing of Adjuvant Chemotherapy for Early Breast Cancer Influence Survival?

Abstract
Purpose: Theoretically, patients with early breast cancer might benefit from starting adjuvant chemotherapy soon after surgery, and this would have important clinical implications. We have addressed this question from a large, single-center database in which the majority of patients received anthracyclines. Patients and Methods: A total of 1,161 patients from a prospectively maintained database treated with adjuvant chemotherapy for early breast cancer at the Royal Marsden Hospital (London, United Kingdom), including 686 (59%) receiving anthracyclines, were retrospectively analyzed. The disease-free survival (DFS) and overall survival (OS) of the 368 patients starting chemotherapy within 21 days of surgery (group A) were compared with those of the 793 patients commencing chemotherapy ≥ 21 days after surgery (group B). Median follow-up time was 39 months (range, 12 to 147 months). Results: No significant difference in 5-year DFS was found between the two groups overall (70% for group A v 72% for group B; P = .4) or in any subgroup. Likewise, there was no difference in 5-year OS (82% for group A v 84% for group B; P = .2) or when the interval to the start of chemotherapy was considered as a continuous variable (P = .4). Conclusion: We have been unable to identify any significant survival benefit from starting adjuvant chemotherapy early after surgery, either overall or in any subset of patients.