e11034 Background: Neoadjuvant chemotherapy(NAC)is one of the treatment options for locally advanced breast cancer. In this study, we evaluated the efficacy and safety of 4 cycles of NAC doxorubicine,docetaxel and cyclophosphamide(TAC),correlation between the response to NAC and molecular classification sub-groups and between the pCR and the time to progression(TTP). Methods: This is a prospective study from January 2005 to December 2008.110 pts with locally advanced breast cancer stage III.All pts have received 4 cycles of NAC based on docetaxel 75 mg/m², doxorubicine 50 mg/m² and cyclophosphamide 500 mg/m² every 3 weeks, followed by surgery.101 pts were assessed, since 9 of them have progressed on treatment and came out of the study. Pts were stratified according to age, menopausal status, histopathological analysis (luminal tumors(ER-positive and HER2-negative), triple-negative tumors (TN)and HER2-positive tumors), response to the treatment and survival. The median follow up of patients was 39 months. The statistical study was done using SPSS 17. Results: The median age was 41(23–65).30% of pts were younger than 35 and 80% were premenopausal. 55% luminal tumors(56 pts), 33% HER2 positive(33 pts) and 12 % TN(12 pts).CRR was estimated at 89%(37% of CR and 63% of PR).There were 23, 7% of pCR according to Chevallier’s classification. In luminal, TN and HER2-positive pCR rates were 16%(9 of 56), 66,6%(8 of 12), and 21,2%(7 of 33) respectively. Multivariate analysis showed that the ER status was the only significant predictor of pCR(P = 0.025).HER2 status was not significantly associated with pCR(P= 0,423).TTP was 50 months. In luminal tumors, TN and HER2-positive tumors the TTP was respectively 59, 52 and 49 months. There was not a significant difference in TTP between the pCR(51 months) and the non-pCR group(44 months)(CI 95, p= 0.109).Grade III/IV toxicity included neutropenia(22%), febrile neutropenia(6,5%), mucositis(13%), and diarrhea(4%). Conclusions: Breast cancer occurs in young women in Algeria. In this study, neoadjuvant TAC was effective and well tolerated. The ER status was the only significant predictor of pCR. The molecular classification group with the highest percentage of pCR was the TN group. pCR was not associated with a better prognosis.
154P Five-year follow-up of the phase III study comparing SB3 (trastuzumab biosimilar) and reference trastuzumab in patients with HER2 positive early or locally advanced breast cancer