0179 Weekly paclitaxel and carboplatin is an effective non-anthracycline regimen in preoperative therapy of breast cancer

Goals: Although chemotherapy (CH) has traditionally been the most used neoadjuvant treatment, toxicity is common, and women with estrogen receptor-positive (ER+) tumors have a significantly lower rate of complete pathological response (pCR) compared with those with ER-negative tumors. Methods: Eligible patients were randomly assigned to receive neoadjuvant endocrine therapy (anastrazole 1mg/day or exemestane 25mg/day for 3 months, 121 patients) or chemotherapy (doxorubicin 60mg/m2 with paclitaxel 200mg/m, four 3-week cycles, 118 patients). A median follow up time was 5.6 years. Results: The primary efficacy end point was already reported (Cancer 2007; 110:244−54). Overall objective response (OR=CR+PR) was similar in the endocrine group (64.5%) compared with chemotherapy (63. 6%, P> 0.5). Here we present 5-years disease-free (DFS) and overall survival (OS) rates in both treatment groups. There was no significant difference in DFS and OS rates through 5 years of follow up between the 121 patients who received neoadjuvant endocrine therapy and 118 women who received chemotherapy: 71.0% and 67.7% (p> 0.5); 76.8% and 72.0%, respectively (p= 0.70). Similarly, there was no significant difference between endocrine (EG) and chemotherapy groups (CHG) relative to the incidence of locoregional recurrences and distant metastases (7.9% and 7.3%, P=0.99; 14.8% and 15. 2%, P=0.83). When the 5-year DFS of patients whose tumors showed OR (CR+PR) was compared with patients who had minor respond (no change or progression) the most favourable DFS rate was found in woman with OR (82% vs 58.1% in endocrine group, P=0.05; 82.6% vs 60.4% in chemotherapy group, P=0.05). There was a trend toward higher rates of 5-year DFS among patients with tumors expressing high levels of ER (Allred> 6) in the EG compared with CHG (82.8% vs 69.8%, p = 0.068). Conclusion: In older patients with hormone-sensitive tumors, neoadjuvant endocrine therapy (with aromatase inhibitors) appears at least as effective as neoadjuvant chemotherapy (doxorubicin + paclitaxel) and less toxic.