Randomized phase II clinical trial of comparison of epirubicin (E) plus cyclophosphamide (C) and weekly paclitaxel (P) as primary systemic therapy (PST) in patients (pts) with stages II and III breast cancer (BC)

568 Background: Response and survival rates achieved by anthracycline and P (q 3 weeks [W]) pts with metastatic BC are comparable (ECOG1193). Weekly P is expected to produce higher response rates and lower hematologic toxicity than tri-weekly P for PST (MDACC2002). This study evaluated the activity and toxicity of weekly P therapy compared with EC therapy for stage II and III BC treated by PST. The primary endpoint was the pathologic complete response(pCR) rate. Methods: Pts with histologically confirmed BC, stage II or III, performance status 0–2, and absence of prior chemotherapy were randomized to either Arm A (EC: E 75mg/m2 and C 600 mg/m2 every 3 W for 4 cycles) or Arm B (weekly P: P 80 mg/m2 weekly for 12 W). Pts received PST for 12 W, then underwent surgery. All pts received a cross-over regimen as adjuvant chemotherapy after surgery. Results: Between November 2003 and May 2006, 171 pts were recruited. One hundred fifty-six pts (Arm A: n=80, Arm B: n=76) were evaluable. The clinicopathologic charac...