title: Exemestane for breast cancer prevention: a critical shift?
abstract: The Mammary Prevention 3 (MAP.3) placebo-controlled randomized trial in 4,560 high-risk postmenopausal women showed a 65% reduction in invasive breast cancer with the use of exemestane at 35 months median follow-up. Few differences in adverse events were observed between the arms, suggesting a promising risk:benefit balance with exemestane for use in chemoprevention. Yet, the MAP.3 design and implementation raise concerns regarding limited data maturity and not prospectively including key bone-related and other toxicities as study end points. Exemestane for prevention is juxtaposed against selective estrogen receptor modulators and the other aromatase inhibitors. Additional issues for prevention, including the influence of obesity, alternative dosing, and biomarker use in phase III trials, are addressed.
  
  
  CONCLUSIONS
  The recently completed MAP.3 trial of exemestane for breast cancer prevention offers a potential new standard for pharmaceutical risk reduction in high-risk postmenopausal women. In addition to describing key findings from the publication of MAP.3 and related trials, our review undertakes a detailed analysis of the strengths and weaknesses of MAP.3 as well as the implications for future prevention research.
authors.affiliation: Division of Medical Oncology, Office of the Scientific Director, E. O. Ospedali Galliera, Genoa, Italy. andrea.decensi@galliera.it
authors.forename: Andrea
authors.initials: A
authors.lastname: Decensi
authors.forename: Barbara K
authors.initials: BK
authors.lastname: Dunn
authors.forename: Matteo
authors.initials: M
authors.lastname: Puntoni
authors.forename: Alessandra
authors.initials: A
authors.lastname: Gennari
authors.forename: Leslie G
authors.initials: LG
authors.lastname: Ford
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000730:Androstadienes / Q000627:therapeutic use*; D016588:Anticarcinogenic Agents / Q000627:therapeutic use*; D047072:Aromatase Inhibitors / Q000627:therapeutic use*; D001943:Breast Neoplasms / Q000188:drug therapy / Q000517:prevention & control*; D005260:Female; D006801:Humans; D008875:Middle Aged; D012307:Risk Factors
chemical_list: D000730:Androstadienes; D016588:Anticarcinogenic Agents; D047072:Aromatase Inhibitors; C056516:exemestane