Prognosis value of hormonal and HER2 receptors on overall survival (OS) and disease-free interval (DFI) in metastatic breast cancer (MBC)

Abstract

1077 Background: In MBC, positive HR constitute a favourable prognostic factor and predict response to an hormonal therapy. Conversely HER-2 overexpression is an adverse prognostic factor associated with a more aggressive tumor. In this retrospective study we analysed overall survival (OS) and disease-free interval (DFI) of three phenotypes: HR-/HER-2- (triple negative); HR+/HER-2- (luminal) and HER-2 overexpression (HER-2+). Methods: We evaluated 511 patients with a MBC treated at Centre Jean Perrin from 1973 to 2006. A comparative lecture of oestrogenic, progestative and HER-2 receptors was performed by IHC. At present, HR and HER-2 status were re-evaluated on 166 initial tumor sample of this data base by two pathologists (study currently ongoing). Median age of patients was 54.8 years. 120 (23.6%) patients were directly metastatic (M1), 391 (76.4%) relapsed distantly (M0). Metastatic patients received a median number of 2 lines of chemotherapy (range, 0–14) and/or a median number of 1 line (range, 0–8) of hormonotherapy. 92 (55.4%) patients had a luminal phenotype, 48 patients (28.9%) were HER-2+ and 26 patients (15.7%) were triple negative. Results: Among these 166 tumors, OS was significantly different between these three populations (p=0.00056). DFI variation was not signicant (p=0.083). These data showed that: - Luminal phenotype had the better OS (median survival of 36.5 months) and DFI (51.09 months) - HER-2+ phenotype (33 of 48 patients were treated with trastuzumab from 1999) had an intermediate prognostic on OS (median survival of 31.1 months) and DFI (42.2 months) - Triple negative phenotype had a poor prognostic on OS (median survival of 12.8 months) and the worse DFI (32.64 months) Conclusions: In metastatic breast cancer, luminal phenotype patients had the best OS; HER-2+ phenotype (treated by herceptin) had an intermediate OS, and triple negative phenotype had the worse OS. No significant financial relationships to disclose.