title: Aromatase inhibitors and breast cancer prevention.
abstract: BACKGROUND
  Endocrine therapy with selective estrogen receptor modulators (SERMs) has been the mainstay of breast cancer prevention trials to date. The aromatase inhibitors, which inhibit the final chemical conversion of androgens to estrogens, have shown increased disease-free survival benefit over tamoxifen in patients with primary hormone receptor-positive breast cancer, as well as reducing the risk of developing contralateral breast cancers. The aromatase inhibitors are being actively evaluated as prevention agents for women with a history of ductal carcinoma in situ as well as for women who are considered to be at high risk for developing primary invasive breast cancer.
  
  
  METHODS
  This review evaluates the available prevention data, as evidenced by the decrease in contralateral breast cancers, when aromatase inhibitors are used in the adjuvant setting, as well as the emerging data of the aromatase inhibitors specifically tested in the prevention setting for women at high risk.
  
  
  CONCLUSIONS
  Exemestane is a viable option for breast cancer prevention. We continue to await further follow-up on exemestane as well as other aromatase inhibitors in the prevention setting for women at high risk of developing breast cancer or with a history of ductal carcinoma in situ.
authors.affiliation: The University of Texas MD Anderson Cancer Center, Department of Breast Medical Oncology , 1515 Holcombe Boulevard, Unit 1354, Houston, TX 77030 , USA. jlitton@mdanderson.org
authors.forename: Jennifer Keating
authors.initials: JK
authors.lastname: Litton
authors.forename: Banu K
authors.initials: BK
authors.lastname: Arun
authors.forename: Powel H
authors.initials: PH
authors.lastname: Brown
authors.forename: Gabriel N
authors.initials: GN
authors.lastname: Hortobagyi
mesh_terms: D016588:Anticarcinogenic Agents / Q000009:adverse effects / Q000627:therapeutic use*; D018931:Antineoplastic Agents, Hormonal / Q000009:adverse effects / Q000627:therapeutic use*; D047072:Aromatase Inhibitors / Q000009:adverse effects / Q000627:therapeutic use*; D001943:Breast Neoplasms / Q000188:drug therapy* / Q000201:enzymology / Q000401:mortality / Q000473:pathology / Q000517:prevention & control*; D018270:Carcinoma, Ductal, Breast / Q000188:drug therapy* / Q000201:enzymology / Q000473:pathology / Q000517:prevention & control*; D017024:Chemotherapy, Adjuvant; D018572:Disease-Free Survival; D055317:Evidence-Based Practice; D005260:Female; D006801:Humans; D020360:Neoadjuvant Therapy; D009376:Neoplasms, Hormone-Dependent / Q000188:drug therapy* / Q000201:enzymology / Q000473:pathology / Q000517:prevention & control*; D018579:Patient Selection; D018570:Risk Assessment; D012307:Risk Factors; D013997:Time Factors; D016896:Treatment Outcome
chemical_list: D016588:Anticarcinogenic Agents; D018931:Antineoplastic Agents, Hormonal; D047072:Aromatase Inhibitors