title: Efficacy of exemestane in korean patients with metastatic breast cancer after failure of nonsteroidal aromatase inhibitors.
abstract: OBJECTIVE
  Exemestane has shown good efficacy and tolerability in postmenopausal women with hormone receptor-positive metastatic breast cancer. However, clinical outcomes in Korean patients have not yet been reported.
  
  
  METHODS
  Data on 112 postmenopausal women with metastatic breast cancer were obtained retrospectively. Clinicopathological characteristics and treatment history were extracted from medical records. All patients received 25 mg exemestane daily until objective disease progression. Progression-free survival (PFS) was the primary endpoint, and secondary endpoints were overall survival (OS), objective response rate (ORR), and clinical benefit rate (CBR=complete response+partial response+stable disease for 6 months).
  
  
  RESULTS
  The median age of the subjects was 55 years (range, 28-76 years). Exemestane treatment resulted in a median PFS of 5.7 months (95% confidence interval [CI], 4.4-7.0 months) and median OS of 21.9 months (95% CI, 13.6-30.3 months). ORR was 6.4% and CBR was 46.4% for the 110 patients with evaluable lesions. Symptomatic visceral disease was independently associated with shorter PFS (hazard ratio, 3.611; 95% CI, 1.904-6.848; p<0.001), compared with bone-dominant disease in a multivariate analysis of PFS after adjusting for age, hormone receptor, human epidermal growth factor receptor 2, Ki-67 status, dominant metastasis site, and sensitivity to nonsteroidal aromatase inhibitor (AI) treatment. Sensitivity to previous nonsteroidal AI treatment was not associated with PFS, suggesting no cross-resistance between exemestane and nonsteroidal AIs.
  
  
  CONCLUSIONS
  Exemestane was effective in postmenopausal Korean women with hormone receptor-positive metastatic breast cancer who failed previous nonsteroidal AI treatment.
authors.affiliation: Department of Internal Medicine, Seoul National University Hospital, Seoul, Korea.
authors.forename: June Koo
authors.initials: JK
authors.lastname: Lee
authors.forename: Seock-Ah
authors.initials: SA
authors.lastname: Im
authors.forename: Daewon
authors.initials: D
authors.lastname: Lee
authors.forename: Ji-Yeon
authors.initials: JY
authors.lastname: Kim
authors.forename: Yoojoo
authors.initials: Y
authors.lastname: Lim
authors.forename: Eunyoung
authors.initials: E
authors.lastname: Lee
authors.forename: Hyeong-Gon
authors.initials: HG
authors.lastname: Moon
authors.forename: Tae-Yong
authors.initials: TY
authors.lastname: Kim
authors.forename: Sae-Won
authors.initials: SW
authors.lastname: Han
authors.forename: Do-Youn
authors.initials: DY
authors.lastname: Oh
authors.forename: Se-Hoon
authors.initials: SH
authors.lastname: Lee
authors.forename: Wonshik
authors.initials: W
authors.lastname: Han
authors.forename: Dong-Wan
authors.initials: DW
authors.lastname: Kim
authors.forename: Tae-You
authors.initials: TY
authors.lastname: Kim
authors.forename: Dong-Young
authors.initials: DY
authors.lastname: Noh
keywords: Aromatase inhibitors; Breast neoplasms; Exemestane; Neoplasm metastasis