A multicenter randomized phase II study of sequential epirubicin/cyclophosphamide (EC) followed by docetaxel (D) with or without celecoxib (Cx) or trastuzumab (Tr) according to HER2 status, as primary chemotherapy (PCT) for localized invasive breast cancer (BC) patients (pts): results of the planned interim analysis

3511 Aims: (1) to assess antitumor activity of sequential EC (75/750 mg/m²) q3w x 4 followed by D (100 mg/m²) q3w x 4, with the randomized addition of Cx (Her2-ve pts) or Tr (Her2+ve pts) vs no additional treatment, in terms of externally reviewed pathological complete response (pCR, defined as absence of residual invasive breast carcinoma and of nodal involvement,)on the first 170 pts randomized form may 2004 to april 2006 , and (2) to correlate these responses to Circulating tumour cells (CTC) , gene expression profile (GEP) (RTPCR, DNA array), p53 function (Yeast functional assay), Results (table 1) Discussion: This planned interim ITT analysis (Fleming’s sequential design) confirms that presurgical addition of Tr to D in ECD sequence improves the pCR rate,yet not to the extent reported with a protracted co-administration before surgery (JCO 23:3676). We also observed a lower pCR rate than previously described with similar PCT. CTC lack sensitivity and specificity due to the low number of detected cells (median 1.5/ml).Ongoing analysis of p53 mutations - a major predictor of pCR with anthracycline-based chemotherapy - and of GEP will be reported and should help clarifying these apparent discrepancies. Supported by PHRC AOM/2002/02117, Pfizer Inc., Roche Pharma, Sanofi-Aventis