Endocrine therapy in patients with metastatic breast cancers (MBC): Prognosis and measures of outcome.

e13070 Background: Endocrine manipulation is the cornerstone of therapy in hormone receptor (HR)-positive breast cancer. However, a significant percentage of patients who receive endocrine therapy (ET) as metastatic treatment experience de novo or acquired resistance. New clinical trials for HR-positive MBC should be tailored around immunophenotypical and clinical features. This study evaluates different potential prognostic factors in patients treated with ET for MBC. Methods: We analyzed retrospectively data from a series of 280 consecutive patients with HR-positive MBC diagnosed from January 2004 to February 2011 at University Hospital of Udine, Italy. Multivariate analysis was performed to establish the independent value of different disease and patients’ characteristics in influencing progression-free survival (PFS), overall survival (OS) and survival post-progression (SPP). Results: Median OS was 38.44 months (mo), median PFS at first-line ET was 10.05 mo. Median SPP was 22.74 mo, 15.18 mo, and 15.4...