title: The effect of anastrozole on bone mineral density during the first 5 years of adjuvant treatment in postmenopausal women with early breast cancer.
abstract: OBJECTIVE
  The administration of aromatase inhibitors is associated with bone loss in postmenopausal women. We assessed changes in bone mineral density (BMD) from baseline to 60 months of treatment in patients receiving anastrozole as initial adjuvant therapy.
  
  
  METHODS
  Postmenopausal women with hormone receptor-positive breast cancer receiving anastrozole as adjuvant therapy at our center since 2004 were enrolled in this study. BMD was assessed by dual-energy X-ray absorptiometry at baseline and after 6, 12, 24, 36, 48 and 60 months. Oral bisphosphonate (Bis) treatment was initiated when patients were diagnosed with osteoporosis having a T-score of -2.5 or lower.
  
  
  RESULTS
  Fifty-five patients were enrolled in the study between 2004 and 2011, and the mean follow-up period was 53.6 months. Thirty-five patients were administered Bis (risedronate in 27 patients, alendronate in 8 patients). After 6 months of hormone therapy, BMD decreased by 0.5% from baseline at the lumbar spine (LS) and BMD decreased by 1.5% at the femoral neck (FN). However, BMD increased by 1.9% at the LS and BMD decreased by 1.5% at the FN for 60 months of treatment. In patients treated with upfront Bis (n = 19), 5.4% BMD increase from baseline was noted at the LS whereas in those without Bis (n = 21) BMD decreased by 4.3% from baseline within 24 months (P < 0.0001). Fractures were observed in 4 patients (7.3%), and 1 patient (1.8%) had a fragility fracture.
  
  
  CONCLUSIONS
  Upfront treatment of Bis with anastrozole significantly increased BMD at the LS and an optimal use of Bis would not increase bone fractures.
  
  
  BACKGROUND
  UMIN0000017571.
authors.affiliation: Department of Breast Surgery, Tokyo Women's Medical University Medical Center East, 2-1-10 Nishiogu, Arakawa-ku, Tokyo, 116-8567 Japan.
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Inoue
authors.affiliation: Department of Breast Surgery, Tokyo Women's Medical University Medical Center East, 2-1-10 Nishiogu, Arakawa-ku, Tokyo, 116-8567 Japan.
authors.forename: Akira
authors.initials: A
authors.lastname: Hirano
authors.affiliation: Department of Breast Surgery, Tokyo Women's Medical University Medical Center East, 2-1-10 Nishiogu, Arakawa-ku, Tokyo, 116-8567 Japan.
authors.forename: Kaoru
authors.initials: K
authors.lastname: Ogura
authors.affiliation: Department of Breast Surgery, Tokyo Women's Medical University Medical Center East, 2-1-10 Nishiogu, Arakawa-ku, Tokyo, 116-8567 Japan.
authors.forename: Akinori
authors.initials: A
authors.lastname: Hattori
authors.affiliation: Department of Breast Surgery, Tokyo Women's Medical University Medical Center East, 2-1-10 Nishiogu, Arakawa-ku, Tokyo, 116-8567 Japan.
authors.forename: Mari
authors.initials: M
authors.lastname: Kamimura
authors.affiliation: Department of Breast Surgery, Tokyo Women's Medical University Medical Center East, 2-1-10 Nishiogu, Arakawa-ku, Tokyo, 116-8567 Japan.
authors.forename: Fumie
authors.initials: F
authors.lastname: Okubo
authors.affiliation: Department of Breast Surgery, Tokyo Women's Medical University Medical Center East, 2-1-10 Nishiogu, Arakawa-ku, Tokyo, 116-8567 Japan.
authors.forename: Hiroko
authors.initials: H
authors.lastname: Tagawa
authors.affiliation: Department of Breast Surgery, Tokyo Women's Medical University Medical Center East, 2-1-10 Nishiogu, Arakawa-ku, Tokyo, 116-8567 Japan.
authors.forename: Shiho
authors.initials: S
authors.lastname: Sakaguchi
authors.affiliation: Department of Breast Surgery, Tokyo Women's Medical University Medical Center East, 2-1-10 Nishiogu, Arakawa-ku, Tokyo, 116-8567 Japan.
authors.forename: Jun
authors.initials: J
authors.lastname: Kinoshita
authors.affiliation: Department of Breast Surgery, Tokyo Women's Medical University Medical Center East, 2-1-10 Nishiogu, Arakawa-ku, Tokyo, 116-8567 Japan.
authors.forename: Tadao
authors.initials: T
authors.lastname: Shimizu
keywords: Anastrozole; Aromatase inhibitor; Bisphosphonate; Bone mineral density; Breast cancer