title: Predictors of response to aromatase inhibitors.
abstract: Aromatase inhibitors are now considered to be part of the endocrine treatment for most hormone receptor-positive breast cancer in post-menopausal women for both early and advanced disease. Despite the impressive efficacy of these agents, up to 50% of treated patients exhibit de novo or intrinsic resistance to aromatase inhibitors and hence identification of response predictors is essential to allow treatment to be directed towards responsive populations and for alternative or additional therapies to be offered to resistant patients. Emerging data seem to suggest a role for the conventional tumour markers of oestrogen receptor and progesterone receptor as possible predictors of response but, particularly in the adjuvant setting, the extent to which these are useful has not been fully elucidated. Data from both the neo-adjuvant and advanced disease settings suggest that response to aromatase inhibitors does not appear to be adversely affected by HER-2 overexpression. Within neo-adjuvant aromatase inhibitor studies, the proliferation marker Ki67 has shown a significant correlation with relapse-free survival, suggesting a role in prediction for measurement of Ki67 and other dynamic markers of response. Analysis of multiple gene expression changes over a short treatment period may also have potential clinical utility for prediction of response.
authors.affiliation: Academic Department of Biochemistry, Royal Marsden Hospital, London SW3 6JJ, UK. helen.anderson@icr.ac.uk
authors.forename: Helen
authors.initials: H
authors.lastname: Anderson
authors.forename: Serdar
authors.initials: S
authors.lastname: Bulun
authors.forename: Ian
authors.initials: I
authors.lastname: Smith
authors.forename: Mitch
authors.initials: M
authors.lastname: Dowsett
mesh_terms: D047072:Aromatase Inhibitors / Q000627:therapeutic use*; D015415:Biomarkers; D006801:Humans; D020360:Neoadjuvant Therapy; D009369:Neoplasms / Q000188:drug therapy / Q000201:enzymology / Q000473:pathology; D013997:Time Factors
chemical_list: D047072:Aromatase Inhibitors; D015415:Biomarkers