Epirubicin and docetaxel with or without capecitabine as neoadjuvant treatment for early breast cancer: final results of a randomized phase III study (ABCSG-24)

ABSTRACT Background This randomized phase III trial compared pathologic complete response (pCR) rates of early breast cancer (EBC) following neoadjuvant epirubicin–docetaxel (ED) ± capecitabine (C), and evaluated the addition of trastuzumab in HER2-positive tumors. Patients and methods Patients with invasive breast cancer (except T4d) were randomly assigned to receive six 3-weekly cycles of ED (both 75 mg/m2) ± C (1000 mg/m2, twice daily, days 1–14). Patients with HER2-positive disease were further randomized to receive trastuzumab (8 mg/kg, then 6 mg/kg every 3 weeks) or not. Primary end point: pCR rate at the time of surgery. Results Five hundred thirty-six patients were randomized to ED (n = 266) or EDC (n = 270); 93 patients were further randomized to trastuzumab (n = 44) or not (n = 49). pCR rate was significantly increased with EDC (23.0% versus 15.4% ED, P = 0.027), and nonsignificantly further increased with trastuzumab (38.6% EDC versus 26.5% ED, P = 0.212). Rates of axillary node involvement at surgery and breast conservation were improved with EDC versus ED, but not significantly; the addition of trastuzumab had no further impact. Hormone receptor status, tumor size, grade, and C (all P ≤ 0.035) were independent prognostic factors for pCR. Trastuzumab added to ED ± C significantly increased the number of serious adverse events (35 versus 18; P = 0.020), mainly due to infusion-related reactions. Conclusion These findings show that the integration of C into a neoadjuvant taxane-/anthracycline-based regimen is a feasible, safe, and effective treatment option, with incorporation of trastuzumab in HER2-positive disease. Clinical trial number NCT00309556, www.clinicaltrials.gov .