Abstract P1-11-08: A Multicenter Prospective Phase II Trial of Neo-Adjuvant (FEC 100)/Cisplatin-Docetaxel with or without Trastuzumab in Locally Advanced Breast Cancer. Gulf Oncology Research Group (G0RG-001)

Abstract BACKGROUND: To evaluate the efficacy and safety profile of the (FEC100) followed by cisplatin/docetaxel with or without trastuzumab as primary chemotherapy for patients with locally advanced breast cancer (LABC T2> 4cm, N0-2, M0). METHODS: Eighty (80) patients with LABC (T2-T4, No-N2, M0) received 4 cycles of FEC (100) followed by 4 cycles of cisplatin/docetaxel, followed by definitive surgery and locoregional radiotherapy with or without hormonal therapy. Patients with HER2 positive received trastuzumab concurrently with cisplatin docetaxel for a total of 8 cycles (for a total of 6 months). The primary end point was pathologic complete response (pCR) in breast and/or axilla for HER2 negative and HER2 positive. RESULTS: Seventy nine (79) patients were evaluable for analysis: median age: 43yrs, Premenopausal: 83%, median tumor size: 7.0cm (≥4 - 10), Stage IIB: 24% and IIIA/IIIB: 76%, both ER/PR positive: 56%, Her2/neu (3+) by IHC staining: 39%. Clinical response was 65% complete response and 28% partial response. Breast conserving surgery was performed in: 10 % and MRM in: 90%.Three (3) patients suffered an asymptomatic and reversible decrease in left ventricular ejection fraction. Pathological complete response (pCR) can b summarized as follow: Overall pCR in breast: 37%, in Axilla: 65%, Breast and axilla: 33%. In patients with HER2 Negative: pCR in breast: 19%, in Axilla: 56%, Breast and axilla: 17%.In patients with HER2 positive: pCR in breast: 65%, in Axilla: 77%, Breast and axilla: 58%.Overall the DFS & OS at 3 years were 88% and 98% respectively. CONCLUSIONS: This sequential combination is a safe, feasible and active combination, which associated with high clinical and pathologic response rates, the addition of trastuzumab increased pCR rate in HER2 positive tumors with promising and encouraging outcomes, further investigation of this combination are warranted. Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P1-11-08.