Zoledronic acid for treatment of osteopenia and osteoporosis in women with primary breast cancer undergoing adjuvant aromatase inhibitor therapy.
BACKGROUND
Postmenopausal women with osteoporosis/osteopenia are at increased risk of fracture. Aromatase inhibitors further increase bone loss in these patients. This study evaluates whether zoledronic acid prevents the bone loss expected when these patients initiate letrozole.


METHODS
Postmenopausal women with estrogen and/or progesterone receptor-positive breast cancer and a bone mineral density (BMD) T-score <-2.0 were given letrozole 2.5mg/vitamin D 400 international units daily, calcium 500mg twice daily, and 4mg zoledronic acid every 6 months. The BMD was assessed at baseline and 1 year. The primary endpoint was the mean change in lumbar spine (LS) BMD at 1 year.


RESULTS
Forty-six patients completed 1 year of treatment. LS BMD increased by 2.66% (p=0.01), femoral neck (FN) by 4.81% (p=0.01), and any measured endpoint by 4.55% (p=0.0052).


CONCLUSIONS
Zoledronic acid prevents bone loss in postmenopausal women with osteoporosis/osteopenia starting letrozole and is associated with improvements in BMD.
Hines
Stephanie L
SL
Mayo Clinic Florida, Jacksonville, FL 32224, USA. hines.stephanie@mayo.edu
Sloan
Jeff A
JA
Atherton
Pamela J
PJ
Perez
Edith A
EA
Dakhil
Shaker R
SR
Johnson
David B
DB
Reddy
Pavan S
PS
Dalton
Robert J
RJ
Mattar
Bassam I
BI
Loprinzi
Charles L
CL
D047072:Aromatase Inhibitors / Q000008:administration & dosage; D015519:Bone Density; D050071:Bone Density Conservation Agents / Q000008:administration & dosage*; D001851:Bone Diseases, Metabolic / Q000188:drug therapy*; D001943:Breast Neoplasms / Q000188:drug therapy; D017024:Chemotherapy, Adjuvant; D004164:Diphosphonates / Q000008:administration & dosage*; D005260:Female; D006801:Humans; D007093:Imidazoles / Q000008:administration & dosage*; D000077289:Letrozole; D009570:Nitriles / Q000008:administration & dosage; D010024:Osteoporosis / Q000188:drug therapy; D012307:Risk Factors; D016896:Treatment Outcome; D014230:Triazoles / Q000008:administration & dosage; D000077211:Zoledronic Acid
D047072:Aromatase Inhibitors; D050071:Bone Density Conservation Agents; D004164:Diphosphonates; D007093:Imidazoles; D009570:Nitriles; D014230:Triazoles; D000077211:Zoledronic Acid; D000077289:Letrozole