Impact of Time from Completion of Neoadjuvant Chemotherapy to Surgery on Survival Outcomes in Breast Cancer Patients.

ABSTRACT

BACKGROUND: No studies have examined the impact of the interval from conclusion of neoadjuvant chemotherapy to surgery in breast cancer patients. This study was undertaken to investigate the relationship between time interval from neoadjuvant chemotherapy to surgery and survival outcomes. METHODS: Breast cancer patients diagnosed with stage I-III disease who received neoadjuvant chemotherapy June 1995 to April 2007 were identified. The effect of neoadjuvant chemotherapy to surgery interval, defined as ≤4, 4-6, or >6 weeks, on survival outcomes was examined. Descriptive statistics and Cox proportional hazards models were used. RESULTS: A total of 1101 patients were identified. Median time to surgery was 33 (range 8-159) days; 335 patients (30.4 %) had surgery within 4 weeks of their last dose of neoadjuvant chemotherapy, 524 (47.6 %) within 4-6 weeks, and 242 (22.0 %) after more than 6 weeks. Median follow-up was 94 (range 3-178) months. The 5-year overall survival (OS) estimates were 79, 87, and 81 % in patients who underwent surgery ≤4, 4-6, and >6 weeks after neoadjuvant chemotherapy, respectively (p = 0.03). The three groups did not differ in 5-year recurrence-free survival (RFS) or locoregional recurrence-free survival (LRFS). In multivariable analysis, compared with an interval of ≤4 weeks, patients who underwent surgery at 4-6 or >6 weeks had equivalent OS, LRFS, and RFS; a sensitivity analysis suggested worse OS in patients who underwent surgery at >8 weeks. CONCLUSIONS: Patients with neoadjuvant chemotherapy to surgery intervals of up to 8 weeks had equivalent OS, RFS, and LRFS.