title: Endocrine therapy for advanced/metastatic breast cancer.
abstract: First-line endocrine therapy by estrogen antagonism or suppression of estrogen achieves objective responses (ORs) and clinical benefit (CB) in around 30% and 50% of estrogen receptor-positive metastatic breast cancer patients, respectively. Aromatase inhibitors (AIs) are the most effective treatment in previously untreated postmenopausal women. Tamoxifen is an effective alternative. The optimal endocrine therapy on relapse remains uncertain. Tamoxifen and fulvestrant achieve CB in around 50% of patients and ORs of 10%. CB of exemestane after nonsteroidal AIs is 30% to 50% but ORs are rare. Targeted agents (eg, everolimus) plus endocrine therapy are likely to become increasingly important in overcoming endocrine resistance.
authors.affiliation: Breast Unit, The Royal Marsden NHS Foundation Trust, Fulham Road, London SW3 6JJ, UK. gaia.schiavon@rmh.nhs.uk
authors.forename: Gaia
authors.initials: G
authors.lastname: Schiavon
authors.forename: Ian E
authors.initials: IE
authors.lastname: Smith
mesh_terms: D018931:Antineoplastic Agents, Hormonal / Q000008:administration & dosage / Q000627:therapeutic use*; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use; D047072:Aromatase Inhibitors / Q000008:administration & dosage / Q000627:therapeutic use; D001943:Breast Neoplasms / Q000188:drug therapy* / Q000473:pathology* / Q000601:surgery; D019008:Drug Resistance, Neoplasm; D004967:Estrogens / Q000008:administration & dosage; D005260:Female; D006801:Humans; D008593:Menopause; D009367:Neoplasm Staging; D010052:Ovariectomy; D011372:Progestins / Q000008:administration & dosage; D047428:Protein Kinase Inhibitors / Q000008:administration & dosage; D020845:Selective Estrogen Receptor Modulators / Q000008:administration & dosage; D013629:Tamoxifen / Q000008:administration & dosage / Q000627:therapeutic use
chemical_list: D018931:Antineoplastic Agents, Hormonal; D047072:Aromatase Inhibitors; D004967:Estrogens; D011372:Progestins; D047428:Protein Kinase Inhibitors; D020845:Selective Estrogen Receptor Modulators; D013629:Tamoxifen
keywords: Advanced; Breast cancer; Endocrine resistance; Endocrine therapy; Metastatic