Neoadjuvant chemotherapy and pathologic response: a retrospective cohort

OBJECTIVE To evaluate the complete pathologic response attained by patients diagnosed with locally advanced breast cancer submitted to neoadjuvant chemotherapy based on the doxorubicin/cyclophosphamide regimen followed by paclitaxel. METHODS A retrospective cohort of patients with locally advanced breast cancer, admitted to the Hospital de Câncer de Barretos between 2006 and 2008 submitted to the doxorubicin/cyclophosphamide protocol followed by paclitaxel (4 cycles of doxorubicin 60mg/m² and cyclophosphamide 600mg/m² every 21 days; 4 cycles of paclitaxel 175mg/m² every 21 days). The following variables were assessed: age, menopause, performance status, initial clinical staging, anthropometric data, chemotherapy (dose - duration), toxicity profile, post-treatment staging, surgery, pathologic complete response rate, disease-free survival, and pathological characteristics (type and histological degree, hormonal profile and lymph node involvement). Statistical analysis was performed using a 5% level of significance. RESULTS Of the 434 patients evaluated, 136 were excluded due to error in staging or because they had received another type of chemotherapy. Median age was 50 years, all with performance status 0-1. Median initial clinical size of tumor was 65mm and the median final clinical size of the tumor was 22mm. Fifty-one (17.1%) patients experienced a pathologic complete response. Those with a negative hormonal profile or who were triple-negative (negative Her-2 and hormonal profile) experienced a favorable impact on the pathologic complete response. CONCLUSION Neoadjuvant chemotherapy with doxorubicin/cyclophosphamide followed by paclitaxel provided a pathologic complete response in the population studied in accordance with that observed in the literature. Triple-negative patients had a greater chance of attaining this response.