Sequence Of Anthracyclines And Taxanes In The Neoadjuvant Chemotherapy Of Her2-Negative Breast Cancer: Experience Of A Brazilian Oncological Center.

e12105 Background: The best sequence of anthracyclines and taxanes in the neoadjuvant chemotherapy of HER2-negative breast cancer is still unknown. The aims of this study were to assess the impact of the sequence order in the pathological complete response (pCR) rate, and in the disease free survival (DFS) and overall survival (OS). Methods: We retrospectively reviewed 235 HER2-negative breast cancer women treated with neoadjuvant chemotherapy from 2003 to 2011 at our cancer center. The patients were pooled in two groups: anthracycline-based followed by taxanes (AC-T) and the reverse sequence (T-AC). The chi-square test was performed to verify the homogeneity between the groups and to compare pCR rate among the treatment groups. Cumulative survival probabilities were calculated using the Kaplan-Meier method. Differences between survivals were tested using the log-rank test. Results: The AC-T (n = 161) and T-AC (n = 74) groups were balanced for age, staging, receptor profile and histologic grade. The follow-up was at least five years for each patient. The median age was 50.1 years. Most patients (97%) had stage III tumors and 72 (30%) had triple negative disease. pCR rate was higher in triple negative compared with luminal cases (16.3 vs. 7.3%; p = 0.049). Treatment sequence did not influence the occurrence of pCR (10.5 vs. 8.5%; p = 0.8) or median survival times (DFS: 87.9 vs. 64.1, p = 0.85; OS: 91.1 vs. 71.6 months, p = 0.15), in the AC-T and T-AC groups, respectively. Conclusions: The sequence of neoadjuvant taxane-anthracycline-based chemotherapy regimen in daily practice did not show difference in the evaluated clinical outcomes. The retrospective design and the low number of patients may limit the power of the study to detect statistically significant differences. Phase III trials should be stimulated in this context. [Table: see text]