Survival analysis of breast cancer subtypes assessed by hormone receptors and HER2 tumor expression in Uruguayan women with operable breast cancer.

e21064 Background: Breast cancer (BC) is an heterogeneous disease and the most common cause of cancer death in Uruguayan women. HER2 and hormone receptors (HR) tumor expression define BC subtypes with different prognosis and characteristics. We previously classified BC in the following subtypes: HR+/HER2-, triple negative (TN), HER2+ and reported their relation with clinical and pathologic features. The purpose of this study was to analyze the relationship between these biological subtypes and disease free survival (DFS) in Uruguayan BC patients (pts). Methods: We retrospectively reviewed clinical records from pts who underwent curative surgery for stage I-III invasive BC at the Oncology Units of 4 institutions in Montevideo, Uruguay, between March 2006 and March 2008. HR and HER2 status were assessed by immunohistochemistry (IHC). DFS was estimated using the Kaplan-Meier method and compared across groups using log rank statistics. Results: 169 pts were included ; median follow up was 43 months. At the ti...